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  • Django admin causes high load for one model...

    - by Joe
    In my Django admin, when I try to view/edit objects from one particular model class the memory usage and CPU rockets up and I have to restart the server. I can view the list of objects fine, but the problem comes when I click on one of the objects. Other models are fine. Working with the object in code (i.e. creating and displaying) is ok, the problem only arises when I try to view an object with the admin interface. The class isn't even particularly exotic: class Comment(models.Model): user = models.ForeignKey(User) thing = models.ForeignKey(Thing) date = models.DateTimeField(auto_now_add=True) content = models.TextField(blank=True, null=True) approved = models.BooleanField(default=True) class Meta: ordering = ['-date'] Any ideas? I'm stumped. The only reason I could think of might be that the thing is quite a large object (a few kb), but as I understand it, it wouldn't get loaded until it was needed (correct?).

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  • Which Code Should Go Where in MVC Structure

    - by Oguz
    My problem is in somewhere between model and controller.Everything works perfect for me when I use MVC just for crud (create, read, update, delete).I have separate models for each database table .I access these models from controller , to crud them . For example , in contacts application,I have actions (create, read, update, delete) in controller(contact) to use model's (contact) methods (create, read, update, delete). The problem starts when I try to do something more complicated. There are some complex processes which I do not know where should I put them. For example , in registering user process. I can not just finish this process in user model because , I have to use other models too (sending mails , creating other records for user via other models) and do lots of complex validations via other models. For example , in some complex searching processes , I have to access lots of models (articles, videos, images etc.) Or, sometimes , I have to use apis to decide what I will do next or which database model I will use to record data So where is the place to do this complicated processes. I do not want to do them in controllers , Because sometimes I should use these processes in other controllers too. And I do not want to put these process in models because , I use models as database access layers .May be I am wrong,I want to know . Thank you for your answer .

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  • ASP.NET MVC authorization & permission to use model classes

    - by Tomek
    Hi, This is my first post here, so hello :) Okey, let's get to the point... I am writing my first app in ASP.NET MVC Framework and i have a problem with checking privileges to use instances of model classes (read, edit). Sample code looks like this: // Controller action [CustomAuthorize(Roles="Editor, Admin")] public ActionResult Stats(int id) { User user = userRepository.GetUser(id); if (user == null || !user.Activated || user.Removed) return View("NotFound"); else if (!user.IsCurrentSessionUserOwned) return View("NotAuthorized"); return View(user); } So far authorize attribute protects only controller actions, so my question is: how to make (custom) authorize attribute to check not only user role, usernames but also did i.e. resources instantiated in action methods (above: User class, but there are other ORM objects like News, Photos etc.) All of these object to check have their unique ID's, so user have own ID, News have their ID and UserID field referecned to Users table (i mean these objects are LINQ2SQL classes). How should i resolve that problem?

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  • MVC2 Areas not Registering Correctly

    - by Geoffrey
    I believe I have my Areas setup correctly (they were working in MVC1 fine). I followed the guide here: http://odetocode.com/Blogs/scott/archive/2009/10/13/asp-net-mvc2-preview-2-areas-and-routes.aspx I've also used Haacked's Route Debugger. Which shows the correct Area/Controller registration when I run it. However when I try to go to my (AreaName)/(Controller) I get this error: "The resource cannot be found." I believe this indicates there's a problem with the routing, but I'm having trouble debugging this. Where should I set my breakpoints to catch routing errors in MVC2? I'm also using SparkViewEngine compiled against MVC2 references. Could this possibly be causing this error? I've set breakpoints on the controller in the area and it never fires off, I assumed the view engine doesn't kick in until after the controller has been initiated, but I could be wrong. The non-area landing page works fine, and I've stripped my project of all areas except one, to avoid any sort of naming conflicts. Any ideas where I can try to look next?

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  • How can I create a horizontal table in a single foreach loop in MVC?

    - by GenericTypeTea
    Is there any way, in ASP.Net MVC, to condense the following code to a single foreach loop? <table class="table"> <tr> <td> Name </td> <% foreach (var item in Model) { %> <td> <%= item.Name %> </td> <% } %> </tr> <tr> <td> Item </td> <% foreach (var item in Model) { %> <td> <%= item.Company %> </td> <% } %> </tr> </table> Where model is a simple object: public class SomeObject { public virtual Name {get;set;} public virtual Company {get;set;} } This would output a table as follows: Name | Bob | Sam | Bill | Steve | Company | Builder | Fireman | MS | Apple | I know I could probably use an extension method to write out each row, but is it possible to build all rows using a single iteration over the model? This is a follow on from this question as I'm unhappy with my accepted answer and cannot believe I've provided the best solution.

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  • Retreive value from model into view ib MVC 3

    - by prerna
    public class HomeController : Controller { public ActionResult Index() { return View(); } /* public string Browse() { return "Hello from Browse"; public string Details(int id) { string message = "Store.Details, ID = " + id; return message; // return "Hello from Details"; }*/ public ActionResult Details(int id) { var album = new Album { Title = "Album " + id }; return View(album); } } I am new to MVC 3 ,My View is Details.aspx without Razor engine. <html> <head runat="server"> <title>Details</title> </head> <body> <div> </div> </body> </html> Can anyone help

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  • edmx - The operation could not be completed - When adding Inheritance

    - by vdh_ant
    Hey guys I have an edmx model which I have draged 2 tables onto - One called 'File' and the other 'ApplicaitonFile'. These two tables have a 1 to 1 relationship in the database. If I stop here everything works fine. But in my model, I want 'ApplicaitonFile' to inherit from 'File'. So I delete the 1 to 1 relationship then configure 'ApplicaitonFile' from 'File' and then remove the FileId from 'ApplicaitonFile' which was the primary key. (Note I am following the instructions from here). If I leave the model open at this point everything is fine, but as soon as I close it, if I try and reopen it again I get the following error "The operation could not be completed". I have been searching for a solution and found this - http://stackoverflow.com/questions/944050/entity-model-does-not-load but as far as I can tell I don't have a duplicate InheritanceConnectors (although I don't know exactly what I'm looking for but I can't see anything out of the ordinary - like 2 connectors with the same name) and the relationship I originally have is a 1 to 1 not a 1 to 0..1 Any ideas??? this is driving me crazy...

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  • CakePHP model useTable with SQL Views

    - by Chris
    I'm in the process converting our CakePHP-built website from Pervasive to SQL Server 2005. After a lot of hassle the setup I've gotten to work is using the ADODB driver with 'connect' as odbc_mssql. This connects to our database and builds the SQL queries just fine. However, here's the rub: one of our Models was associated with an SQL view in Pervasive. I ported over the view, but it appears using the set up that I have that CakePHP can't find the View in SQL Server. Couldn't find much after some Google searches - has anyone else run into a problem like this? Is there a solution/workaround, or is there some redesign in my future?

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  • Trouble accessing data in relationships in Ember

    - by user3618430
    I'm having trouble saving data in this model relationship. My models are as follows: App.Flow = DS.Model.extend({ title: DS.attr('string'), content: DS.attr('string'), isCustom: DS.attr('boolean'), params: DS.hasMany('parameter', {async: true}) }); App.Parameter = DS.Model.extend({ flow: DS.belongsTo('flow'), param: DS.attr('string'), param_tooltip: DS.attr('string'), param_value: DS.attr('string') }); As you can see, I want Flows to have multiple Parameters. I have a rudimentary setup using Flow and Parameter fixtures, which behave as expected in the templates. However, when I try to create new ones in the controller, I have trouble setting the flow and parameter values correctly. var p = this.store.createRecord('parameter', { param: "foo", param_tooltip: "world", param_value: "hello" }); var f = this.store.createRecord('flow', { title: 'job', content: title, isCustom: true, params: [p] // doesn't seem to work }); f.set('params', [p]); // doesn't seem to work p.set('flow', f); // also doesn't seem to work // Save the new model p.save(); f.save(); I've tried a lot of solutions after staring at this and StackOverflow for a while (not just the ones listed). I'm not really sure what to try next. One thing that I noticed in the Ember inspector was that the ids of these created elements were not integers (they were something like the string 'fixture_0'), but I'm not really sure why that would be, whether its related, or how to fix it. Thanks!

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  • Domain object validation vs view model validation

    - by Brendan Vogt
    I am using ASP.NET MVC 3 and I am using FluentValidation to validate my view models. I am just a little concerned that I might not be on the correct track. As far as what I know, model validation should be done on the domain object. Now with MVC you might have multiple view models that are similar that needs validation. What happens if a property from a domain object occurs in more than one view model? Now you are validating the same property twice, and they might not even be in sync. So if I have a User domain object then I would like to do validation on this object. Now what happens if I have UserAViewModel and UserBViewModel, so now it is multiple validations that needs to be done. The scenario above is just an example, so please don't critise on it.

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  • Modeling Buyers & Sellers in a Rails Ecommerce App

    - by MikeH
    I'm building a Rails app that has Etsy.com style functionality. In other words, it's like a mall. There are many buyers and many sellers. I'm torn about how to model the sellers. Key facts: There won't be many sellers. Perhaps less than 20 sellers in total. There will be many buyers. Hopefully many thousands :) I already have a standard user model in place with account creation and roles. I've created a 'role' of 'seller', which the admin will manually apply to the proper users. Since we'll have very few sellers, this is not an issue. I'm considering two approaches: (1) Create a 'store' model, which will contain all the relevant store information. Products would :belong_to :store, rather than belonging to the seller. The relationship between the user and store models would be: user :has_one store. My main problem with this is that I've always found has_one associations to be a little funky, and I usually try to avoid them. The app is fairly complex, and I'm worried about running into a cascade of problems connected to the has_one association as I get further along into development. (2) Simply include the relevant 'store' information as part of the user model. But in this case, the store-related db columns would only apply to a very small percentage of users since very few users will also be sellers. I'm not sure if this is a valid concern or not. It's very possible that I'm thinking about this incorrectly. I appreciate any thoughts. Thanks.

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  • How do I use a named_scope to filter records in my model

    - by kibyegon
    I have a model "Product" with a "description" field. Now I want to have a link in the index page that when clicked will show all products where the description is blank (empty). In the model I have defined a named_scope like this named_scope :no_description, :conditions => { :description => "" } I have checked that the named_scope works by calling Product.no_description.count on the console. As far as I know, the controller is then supposed to handle the filter request from the link on the "index" action but be able to distinguish it from the default which is view all products. def index @products = Product.all ... My problem is getting the controller handle the different request, what route to setup for the link on the view and the actual link on the view. Hope I explained my problem.

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  • Utility App with Navigation Controller and Table View on FlipSide.

    - by wdt
    Hi All. I am relatively new to the whole MVC way of looking at things. I have an application that is based on the "Utility" Application template. Everything in the MainView and FlipsideView is working great but now I need to add a TableView and Navigation Controller to the flipside. Without the navigation bar being on the MainView. So only once the user has tapped the info light button will the nav bar display on the flipside with a table view. I have been able to impliment the Table View on the side and populate it with data from an array. I am now struggling to link in a navigation controller so that the tableview can become interactive. When I place the nav bar code into the app delegate it appears on the MainView and not the flipside view. Where do I place the navigation bar code so that it will display on the flipsideview. I cannt seem to get the code in the right place. Also I am not sure I have the right code, do I put the UINavigationController code in the FlipSideViewController.m ? I am not grasping the concept of the naivgation controller fully I think . . . Here is the code to bring up the FlipView - (IBAction)showInfo { TableViewController *controller = [[TableViewController alloc] initWithNibName:@"TableViewController" bundle:nil]; controller.delegate = self; controller.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal; [self presentModalViewController:controller animated:YES]; [controller release]; } Now I need to get the TableViewController to have a navigation controller and a table view Thanks in advance.

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  • Introduction to the ASP.NET Web API

    - by Stephen.Walther
    I am a huge fan of Ajax. If you want to create a great experience for the users of your website – regardless of whether you are building an ASP.NET MVC or an ASP.NET Web Forms site — then you need to use Ajax. Otherwise, you are just being cruel to your customers. We use Ajax extensively in several of the ASP.NET applications that my company, Superexpert.com, builds. We expose data from the server as JSON and use jQuery to retrieve and update that data from the browser. One challenge, when building an ASP.NET website, is deciding on which technology to use to expose JSON data from the server. For example, how do you expose a list of products from the server as JSON so you can retrieve the list of products with jQuery? You have a number of options (too many options) including ASMX Web services, WCF Web Services, ASHX Generic Handlers, WCF Data Services, and MVC controller actions. Fortunately, the world has just been simplified. With the release of ASP.NET 4 Beta, Microsoft has introduced a new technology for exposing JSON from the server named the ASP.NET Web API. You can use the ASP.NET Web API with both ASP.NET MVC and ASP.NET Web Forms applications. The goal of this blog post is to provide you with a brief overview of the features of the new ASP.NET Web API. You learn how to use the ASP.NET Web API to retrieve, insert, update, and delete database records with jQuery. We also discuss how you can perform form validation when using the Web API and use OData when using the Web API. Creating an ASP.NET Web API Controller The ASP.NET Web API exposes JSON data through a new type of controller called an API controller. You can add an API controller to an existing ASP.NET MVC 4 project through the standard Add Controller dialog box. Right-click your Controllers folder and select Add, Controller. In the dialog box, name your controller MovieController and select the Empty API controller template: A brand new API controller looks like this: using System; using System.Collections.Generic; using System.Linq; using System.Net.Http; using System.Web.Http; namespace MyWebAPIApp.Controllers { public class MovieController : ApiController { } } An API controller, unlike a standard MVC controller, derives from the base ApiController class instead of the base Controller class. Using jQuery to Retrieve, Insert, Update, and Delete Data Let’s create an Ajaxified Movie Database application. We’ll retrieve, insert, update, and delete movies using jQuery with the MovieController which we just created. Our Movie model class looks like this: namespace MyWebAPIApp.Models { public class Movie { public int Id { get; set; } public string Title { get; set; } public string Director { get; set; } } } Our application will consist of a single HTML page named Movies.html. We’ll place all of our jQuery code in the Movies.html page. Getting a Single Record with the ASP.NET Web API To support retrieving a single movie from the server, we need to add a Get method to our API controller: using System; using System.Collections.Generic; using System.Linq; using System.Net; using System.Net.Http; using System.Web.Http; using MyWebAPIApp.Models; namespace MyWebAPIApp.Controllers { public class MovieController : ApiController { public Movie GetMovie(int id) { // Return movie by id if (id == 1) { return new Movie { Id = 1, Title = "Star Wars", Director = "Lucas" }; } // Otherwise, movie was not found throw new HttpResponseException(HttpStatusCode.NotFound); } } } In the code above, the GetMovie() method accepts the Id of a movie. If the Id has the value 1 then the method returns the movie Star Wars. Otherwise, the method throws an exception and returns 404 Not Found HTTP status code. After building your project, you can invoke the MovieController.GetMovie() method by entering the following URL in your web browser address bar: http://localhost:[port]/api/movie/1 (You’ll need to enter the correct randomly generated port). In the URL api/movie/1, the first “api” segment indicates that this is a Web API route. The “movie” segment indicates that the MovieController should be invoked. You do not specify the name of the action. Instead, the HTTP method used to make the request – GET, POST, PUT, DELETE — is used to identify the action to invoke. The ASP.NET Web API uses different routing conventions than normal ASP.NET MVC controllers. When you make an HTTP GET request then any API controller method with a name that starts with “GET” is invoked. So, we could have called our API controller action GetPopcorn() instead of GetMovie() and it would still be invoked by the URL api/movie/1. The default route for the Web API is defined in the Global.asax file and it looks like this: routes.MapHttpRoute( name: "DefaultApi", routeTemplate: "api/{controller}/{id}", defaults: new { id = RouteParameter.Optional } ); We can invoke our GetMovie() controller action with the jQuery code in the following HTML page: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Get Movie</title> </head> <body> <div> Title: <span id="title"></span> </div> <div> Director: <span id="director"></span> </div> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> getMovie(1, function (movie) { $("#title").html(movie.Title); $("#director").html(movie.Director); }); function getMovie(id, callback) { $.ajax({ url: "/api/Movie", data: { id: id }, type: "GET", contentType: "application/json;charset=utf-8", statusCode: { 200: function (movie) { callback(movie); }, 404: function () { alert("Not Found!"); } } }); } </script> </body> </html> In the code above, the jQuery $.ajax() method is used to invoke the GetMovie() method. Notice that the Ajax call handles two HTTP response codes. When the GetMove() method successfully returns a movie, the method returns a 200 status code. In that case, the details of the movie are displayed in the HTML page. Otherwise, if the movie is not found, the GetMovie() method returns a 404 status code. In that case, the page simply displays an alert box indicating that the movie was not found (hopefully, you would implement something more graceful in an actual application). You can use your browser’s Developer Tools to see what is going on in the background when you open the HTML page (hit F12 in the most recent version of most browsers). For example, you can use the Network tab in Google Chrome to see the Ajax request which invokes the GetMovie() method: Getting a Set of Records with the ASP.NET Web API Let’s modify our Movie API controller so that it returns a collection of movies. The following Movie controller has a new ListMovies() method which returns a (hard-coded) collection of movies: using System; using System.Collections.Generic; using System.Linq; using System.Net; using System.Net.Http; using System.Web.Http; using MyWebAPIApp.Models; namespace MyWebAPIApp.Controllers { public class MovieController : ApiController { public IEnumerable<Movie> ListMovies() { return new List<Movie> { new Movie {Id=1, Title="Star Wars", Director="Lucas"}, new Movie {Id=1, Title="King Kong", Director="Jackson"}, new Movie {Id=1, Title="Memento", Director="Nolan"} }; } } } Because we named our action ListMovies(), the default Web API route will never match it. Therefore, we need to add the following custom route to our Global.asax file (at the top of the RegisterRoutes() method): routes.MapHttpRoute( name: "ActionApi", routeTemplate: "api/{controller}/{action}/{id}", defaults: new { id = RouteParameter.Optional } ); This route enables us to invoke the ListMovies() method with the URL /api/movie/listmovies. Now that we have exposed our collection of movies from the server, we can retrieve and display the list of movies using jQuery in our HTML page: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>List Movies</title> </head> <body> <div id="movies"></div> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> listMovies(function (movies) { var strMovies=""; $.each(movies, function (index, movie) { strMovies += "<div>" + movie.Title + "</div>"; }); $("#movies").html(strMovies); }); function listMovies(callback) { $.ajax({ url: "/api/Movie/ListMovies", data: {}, type: "GET", contentType: "application/json;charset=utf-8", }).then(function(movies){ callback(movies); }); } </script> </body> </html>     Inserting a Record with the ASP.NET Web API Now let’s modify our Movie API controller so it supports creating new records: public HttpResponseMessage<Movie> PostMovie(Movie movieToCreate) { // Add movieToCreate to the database and update primary key movieToCreate.Id = 23; // Build a response that contains the location of the new movie var response = new HttpResponseMessage<Movie>(movieToCreate, HttpStatusCode.Created); var relativePath = "/api/movie/" + movieToCreate.Id; response.Headers.Location = new Uri(Request.RequestUri, relativePath); return response; } The PostMovie() method in the code above accepts a movieToCreate parameter. We don’t actually store the new movie anywhere. In real life, you will want to call a service method to store the new movie in a database. When you create a new resource, such as a new movie, you should return the location of the new resource. In the code above, the URL where the new movie can be retrieved is assigned to the Location header returned in the PostMovie() response. Because the name of our method starts with “Post”, we don’t need to create a custom route. The PostMovie() method can be invoked with the URL /Movie/PostMovie – just as long as the method is invoked within the context of a HTTP POST request. The following HTML page invokes the PostMovie() method. <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Create Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> var movieToCreate = { title: "The Hobbit", director: "Jackson" }; createMovie(movieToCreate, function (newMovie) { alert("New movie created with an Id of " + newMovie.Id); }); function createMovie(movieToCreate, callback) { $.ajax({ url: "/api/Movie", data: JSON.stringify( movieToCreate ), type: "POST", contentType: "application/json;charset=utf-8", statusCode: { 201: function (newMovie) { callback(newMovie); } } }); } </script> </body> </html> This page creates a new movie (the Hobbit) by calling the createMovie() method. The page simply displays the Id of the new movie: The HTTP Post operation is performed with the following call to the jQuery $.ajax() method: $.ajax({ url: "/api/Movie", data: JSON.stringify( movieToCreate ), type: "POST", contentType: "application/json;charset=utf-8", statusCode: { 201: function (newMovie) { callback(newMovie); } } }); Notice that the type of Ajax request is a POST request. This is required to match the PostMovie() method. Notice, furthermore, that the new movie is converted into JSON using JSON.stringify(). The JSON.stringify() method takes a JavaScript object and converts it into a JSON string. Finally, notice that success is represented with a 201 status code. The HttpStatusCode.Created value returned from the PostMovie() method returns a 201 status code. Updating a Record with the ASP.NET Web API Here’s how we can modify the Movie API controller to support updating an existing record. In this case, we need to create a PUT method to handle an HTTP PUT request: public void PutMovie(Movie movieToUpdate) { if (movieToUpdate.Id == 1) { // Update the movie in the database return; } // If you can't find the movie to update throw new HttpResponseException(HttpStatusCode.NotFound); } Unlike our PostMovie() method, the PutMovie() method does not return a result. The action either updates the database or, if the movie cannot be found, returns an HTTP Status code of 404. The following HTML page illustrates how you can invoke the PutMovie() method: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Put Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> var movieToUpdate = { id: 1, title: "The Hobbit", director: "Jackson" }; updateMovie(movieToUpdate, function () { alert("Movie updated!"); }); function updateMovie(movieToUpdate, callback) { $.ajax({ url: "/api/Movie", data: JSON.stringify(movieToUpdate), type: "PUT", contentType: "application/json;charset=utf-8", statusCode: { 200: function () { callback(); }, 404: function () { alert("Movie not found!"); } } }); } </script> </body> </html> Deleting a Record with the ASP.NET Web API Here’s the code for deleting a movie: public HttpResponseMessage DeleteMovie(int id) { // Delete the movie from the database // Return status code return new HttpResponseMessage(HttpStatusCode.NoContent); } This method simply deletes the movie (well, not really, but pretend that it does) and returns a No Content status code (204). The following page illustrates how you can invoke the DeleteMovie() action: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Delete Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> deleteMovie(1, function () { alert("Movie deleted!"); }); function deleteMovie(id, callback) { $.ajax({ url: "/api/Movie", data: JSON.stringify({id:id}), type: "DELETE", contentType: "application/json;charset=utf-8", statusCode: { 204: function () { callback(); } } }); } </script> </body> </html> Performing Validation How do you perform form validation when using the ASP.NET Web API? Because validation in ASP.NET MVC is driven by the Default Model Binder, and because the Web API uses the Default Model Binder, you get validation for free. Let’s modify our Movie class so it includes some of the standard validation attributes: using System.ComponentModel.DataAnnotations; namespace MyWebAPIApp.Models { public class Movie { public int Id { get; set; } [Required(ErrorMessage="Title is required!")] [StringLength(5, ErrorMessage="Title cannot be more than 5 characters!")] public string Title { get; set; } [Required(ErrorMessage="Director is required!")] public string Director { get; set; } } } In the code above, the Required validation attribute is used to make both the Title and Director properties required. The StringLength attribute is used to require the length of the movie title to be no more than 5 characters. Now let’s modify our PostMovie() action to validate a movie before adding the movie to the database: public HttpResponseMessage PostMovie(Movie movieToCreate) { // Validate movie if (!ModelState.IsValid) { var errors = new JsonArray(); foreach (var prop in ModelState.Values) { if (prop.Errors.Any()) { errors.Add(prop.Errors.First().ErrorMessage); } } return new HttpResponseMessage<JsonValue>(errors, HttpStatusCode.BadRequest); } // Add movieToCreate to the database and update primary key movieToCreate.Id = 23; // Build a response that contains the location of the new movie var response = new HttpResponseMessage<Movie>(movieToCreate, HttpStatusCode.Created); var relativePath = "/api/movie/" + movieToCreate.Id; response.Headers.Location = new Uri(Request.RequestUri, relativePath); return response; } If ModelState.IsValid has the value false then the errors in model state are copied to a new JSON array. Each property – such as the Title and Director property — can have multiple errors. In the code above, only the first error message is copied over. The JSON array is returned with a Bad Request status code (400 status code). The following HTML page illustrates how you can invoke our modified PostMovie() action and display any error messages: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Create Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> var movieToCreate = { title: "The Hobbit", director: "" }; createMovie(movieToCreate, function (newMovie) { alert("New movie created with an Id of " + newMovie.Id); }, function (errors) { var strErrors = ""; $.each(errors, function(index, err) { strErrors += "*" + err + "\n"; }); alert(strErrors); } ); function createMovie(movieToCreate, success, fail) { $.ajax({ url: "/api/Movie", data: JSON.stringify(movieToCreate), type: "POST", contentType: "application/json;charset=utf-8", statusCode: { 201: function (newMovie) { success(newMovie); }, 400: function (xhr) { var errors = JSON.parse(xhr.responseText); fail(errors); } } }); } </script> </body> </html> The createMovie() function performs an Ajax request and handles either a 201 or a 400 status code from the response. If a 201 status code is returned then there were no validation errors and the new movie was created. If, on the other hand, a 400 status code is returned then there was a validation error. The validation errors are retrieved from the XmlHttpRequest responseText property. The error messages are displayed in an alert: (Please don’t use JavaScript alert dialogs to display validation errors, I just did it this way out of pure laziness) This validation code in our PostMovie() method is pretty generic. There is nothing specific about this code to the PostMovie() method. In the following video, Jon Galloway demonstrates how to create a global Validation filter which can be used with any API controller action: http://www.asp.net/web-api/overview/web-api-routing-and-actions/video-custom-validation His validation filter looks like this: using System.Json; using System.Linq; using System.Net; using System.Net.Http; using System.Web.Http.Controllers; using System.Web.Http.Filters; namespace MyWebAPIApp.Filters { public class ValidationActionFilter:ActionFilterAttribute { public override void OnActionExecuting(HttpActionContext actionContext) { var modelState = actionContext.ModelState; if (!modelState.IsValid) { dynamic errors = new JsonObject(); foreach (var key in modelState.Keys) { var state = modelState[key]; if (state.Errors.Any()) { errors[key] = state.Errors.First().ErrorMessage; } } actionContext.Response = new HttpResponseMessage<JsonValue>(errors, HttpStatusCode.BadRequest); } } } } And you can register the validation filter in the Application_Start() method in the Global.asax file like this: GlobalConfiguration.Configuration.Filters.Add(new ValidationActionFilter()); After you register the Validation filter, validation error messages are returned from any API controller action method automatically when validation fails. You don’t need to add any special logic to any of your API controller actions to take advantage of the filter. Querying using OData The OData protocol is an open protocol created by Microsoft which enables you to perform queries over the web. The official website for OData is located here: http://odata.org For example, here are some of the query options which you can use with OData: · $orderby – Enables you to retrieve results in a certain order. · $top – Enables you to retrieve a certain number of results. · $skip – Enables you to skip over a certain number of results (use with $top for paging). · $filter – Enables you to filter the results returned. The ASP.NET Web API supports a subset of the OData protocol. You can use all of the query options listed above when interacting with an API controller. The only requirement is that the API controller action returns its data as IQueryable. For example, the following Movie controller has an action named GetMovies() which returns an IQueryable of movies: public IQueryable<Movie> GetMovies() { return new List<Movie> { new Movie {Id=1, Title="Star Wars", Director="Lucas"}, new Movie {Id=2, Title="King Kong", Director="Jackson"}, new Movie {Id=3, Title="Willow", Director="Lucas"}, new Movie {Id=4, Title="Shrek", Director="Smith"}, new Movie {Id=5, Title="Memento", Director="Nolan"} }.AsQueryable(); } If you enter the following URL in your browser: /api/movie?$top=2&$orderby=Title Then you will limit the movies returned to the top 2 in order of the movie Title. You will get the following results: By using the $top option in combination with the $skip option, you can enable client-side paging. For example, you can use $top and $skip to page through thousands of products, 10 products at a time. The $filter query option is very powerful. You can use this option to filter the results from a query. Here are some examples: Return every movie directed by Lucas: /api/movie?$filter=Director eq ‘Lucas’ Return every movie which has a title which starts with ‘S’: /api/movie?$filter=startswith(Title,’S') Return every movie which has an Id greater than 2: /api/movie?$filter=Id gt 2 The complete documentation for the $filter option is located here: http://www.odata.org/developers/protocols/uri-conventions#FilterSystemQueryOption Summary The goal of this blog entry was to provide you with an overview of the new ASP.NET Web API introduced with the Beta release of ASP.NET 4. In this post, I discussed how you can retrieve, insert, update, and delete data by using jQuery with the Web API. I also discussed how you can use the standard validation attributes with the Web API. You learned how to return validation error messages to the client and display the error messages using jQuery. Finally, we briefly discussed how the ASP.NET Web API supports the OData protocol. For example, you learned how to filter records returned from an API controller action by using the $filter query option. I’m excited about the new Web API. This is a feature which I expect to use with almost every ASP.NET application which I build in the future.

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  • Introduction to the ASP.NET Web API

    - by Stephen.Walther
    I am a huge fan of Ajax. If you want to create a great experience for the users of your website – regardless of whether you are building an ASP.NET MVC or an ASP.NET Web Forms site — then you need to use Ajax. Otherwise, you are just being cruel to your customers. We use Ajax extensively in several of the ASP.NET applications that my company, Superexpert.com, builds. We expose data from the server as JSON and use jQuery to retrieve and update that data from the browser. One challenge, when building an ASP.NET website, is deciding on which technology to use to expose JSON data from the server. For example, how do you expose a list of products from the server as JSON so you can retrieve the list of products with jQuery? You have a number of options (too many options) including ASMX Web services, WCF Web Services, ASHX Generic Handlers, WCF Data Services, and MVC controller actions. Fortunately, the world has just been simplified. With the release of ASP.NET 4 Beta, Microsoft has introduced a new technology for exposing JSON from the server named the ASP.NET Web API. You can use the ASP.NET Web API with both ASP.NET MVC and ASP.NET Web Forms applications. The goal of this blog post is to provide you with a brief overview of the features of the new ASP.NET Web API. You learn how to use the ASP.NET Web API to retrieve, insert, update, and delete database records with jQuery. We also discuss how you can perform form validation when using the Web API and use OData when using the Web API. Creating an ASP.NET Web API Controller The ASP.NET Web API exposes JSON data through a new type of controller called an API controller. You can add an API controller to an existing ASP.NET MVC 4 project through the standard Add Controller dialog box. Right-click your Controllers folder and select Add, Controller. In the dialog box, name your controller MovieController and select the Empty API controller template: A brand new API controller looks like this: using System; using System.Collections.Generic; using System.Linq; using System.Net.Http; using System.Web.Http; namespace MyWebAPIApp.Controllers { public class MovieController : ApiController { } } An API controller, unlike a standard MVC controller, derives from the base ApiController class instead of the base Controller class. Using jQuery to Retrieve, Insert, Update, and Delete Data Let’s create an Ajaxified Movie Database application. We’ll retrieve, insert, update, and delete movies using jQuery with the MovieController which we just created. Our Movie model class looks like this: namespace MyWebAPIApp.Models { public class Movie { public int Id { get; set; } public string Title { get; set; } public string Director { get; set; } } } Our application will consist of a single HTML page named Movies.html. We’ll place all of our jQuery code in the Movies.html page. Getting a Single Record with the ASP.NET Web API To support retrieving a single movie from the server, we need to add a Get method to our API controller: using System; using System.Collections.Generic; using System.Linq; using System.Net; using System.Net.Http; using System.Web.Http; using MyWebAPIApp.Models; namespace MyWebAPIApp.Controllers { public class MovieController : ApiController { public Movie GetMovie(int id) { // Return movie by id if (id == 1) { return new Movie { Id = 1, Title = "Star Wars", Director = "Lucas" }; } // Otherwise, movie was not found throw new HttpResponseException(HttpStatusCode.NotFound); } } } In the code above, the GetMovie() method accepts the Id of a movie. If the Id has the value 1 then the method returns the movie Star Wars. Otherwise, the method throws an exception and returns 404 Not Found HTTP status code. After building your project, you can invoke the MovieController.GetMovie() method by entering the following URL in your web browser address bar: http://localhost:[port]/api/movie/1 (You’ll need to enter the correct randomly generated port). In the URL api/movie/1, the first “api” segment indicates that this is a Web API route. The “movie” segment indicates that the MovieController should be invoked. You do not specify the name of the action. Instead, the HTTP method used to make the request – GET, POST, PUT, DELETE — is used to identify the action to invoke. The ASP.NET Web API uses different routing conventions than normal ASP.NET MVC controllers. When you make an HTTP GET request then any API controller method with a name that starts with “GET” is invoked. So, we could have called our API controller action GetPopcorn() instead of GetMovie() and it would still be invoked by the URL api/movie/1. The default route for the Web API is defined in the Global.asax file and it looks like this: routes.MapHttpRoute( name: "DefaultApi", routeTemplate: "api/{controller}/{id}", defaults: new { id = RouteParameter.Optional } ); We can invoke our GetMovie() controller action with the jQuery code in the following HTML page: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Get Movie</title> </head> <body> <div> Title: <span id="title"></span> </div> <div> Director: <span id="director"></span> </div> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> getMovie(1, function (movie) { $("#title").html(movie.Title); $("#director").html(movie.Director); }); function getMovie(id, callback) { $.ajax({ url: "/api/Movie", data: { id: id }, type: "GET", contentType: "application/json;charset=utf-8", statusCode: { 200: function (movie) { callback(movie); }, 404: function () { alert("Not Found!"); } } }); } </script> </body> </html> In the code above, the jQuery $.ajax() method is used to invoke the GetMovie() method. Notice that the Ajax call handles two HTTP response codes. When the GetMove() method successfully returns a movie, the method returns a 200 status code. In that case, the details of the movie are displayed in the HTML page. Otherwise, if the movie is not found, the GetMovie() method returns a 404 status code. In that case, the page simply displays an alert box indicating that the movie was not found (hopefully, you would implement something more graceful in an actual application). You can use your browser’s Developer Tools to see what is going on in the background when you open the HTML page (hit F12 in the most recent version of most browsers). For example, you can use the Network tab in Google Chrome to see the Ajax request which invokes the GetMovie() method: Getting a Set of Records with the ASP.NET Web API Let’s modify our Movie API controller so that it returns a collection of movies. The following Movie controller has a new ListMovies() method which returns a (hard-coded) collection of movies: using System; using System.Collections.Generic; using System.Linq; using System.Net; using System.Net.Http; using System.Web.Http; using MyWebAPIApp.Models; namespace MyWebAPIApp.Controllers { public class MovieController : ApiController { public IEnumerable<Movie> ListMovies() { return new List<Movie> { new Movie {Id=1, Title="Star Wars", Director="Lucas"}, new Movie {Id=1, Title="King Kong", Director="Jackson"}, new Movie {Id=1, Title="Memento", Director="Nolan"} }; } } } Because we named our action ListMovies(), the default Web API route will never match it. Therefore, we need to add the following custom route to our Global.asax file (at the top of the RegisterRoutes() method): routes.MapHttpRoute( name: "ActionApi", routeTemplate: "api/{controller}/{action}/{id}", defaults: new { id = RouteParameter.Optional } ); This route enables us to invoke the ListMovies() method with the URL /api/movie/listmovies. Now that we have exposed our collection of movies from the server, we can retrieve and display the list of movies using jQuery in our HTML page: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>List Movies</title> </head> <body> <div id="movies"></div> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> listMovies(function (movies) { var strMovies=""; $.each(movies, function (index, movie) { strMovies += "<div>" + movie.Title + "</div>"; }); $("#movies").html(strMovies); }); function listMovies(callback) { $.ajax({ url: "/api/Movie/ListMovies", data: {}, type: "GET", contentType: "application/json;charset=utf-8", }).then(function(movies){ callback(movies); }); } </script> </body> </html>     Inserting a Record with the ASP.NET Web API Now let’s modify our Movie API controller so it supports creating new records: public HttpResponseMessage<Movie> PostMovie(Movie movieToCreate) { // Add movieToCreate to the database and update primary key movieToCreate.Id = 23; // Build a response that contains the location of the new movie var response = new HttpResponseMessage<Movie>(movieToCreate, HttpStatusCode.Created); var relativePath = "/api/movie/" + movieToCreate.Id; response.Headers.Location = new Uri(Request.RequestUri, relativePath); return response; } The PostMovie() method in the code above accepts a movieToCreate parameter. We don’t actually store the new movie anywhere. In real life, you will want to call a service method to store the new movie in a database. When you create a new resource, such as a new movie, you should return the location of the new resource. In the code above, the URL where the new movie can be retrieved is assigned to the Location header returned in the PostMovie() response. Because the name of our method starts with “Post”, we don’t need to create a custom route. The PostMovie() method can be invoked with the URL /Movie/PostMovie – just as long as the method is invoked within the context of a HTTP POST request. The following HTML page invokes the PostMovie() method. <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Create Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> var movieToCreate = { title: "The Hobbit", director: "Jackson" }; createMovie(movieToCreate, function (newMovie) { alert("New movie created with an Id of " + newMovie.Id); }); function createMovie(movieToCreate, callback) { $.ajax({ url: "/api/Movie", data: JSON.stringify( movieToCreate ), type: "POST", contentType: "application/json;charset=utf-8", statusCode: { 201: function (newMovie) { callback(newMovie); } } }); } </script> </body> </html> This page creates a new movie (the Hobbit) by calling the createMovie() method. The page simply displays the Id of the new movie: The HTTP Post operation is performed with the following call to the jQuery $.ajax() method: $.ajax({ url: "/api/Movie", data: JSON.stringify( movieToCreate ), type: "POST", contentType: "application/json;charset=utf-8", statusCode: { 201: function (newMovie) { callback(newMovie); } } }); Notice that the type of Ajax request is a POST request. This is required to match the PostMovie() method. Notice, furthermore, that the new movie is converted into JSON using JSON.stringify(). The JSON.stringify() method takes a JavaScript object and converts it into a JSON string. Finally, notice that success is represented with a 201 status code. The HttpStatusCode.Created value returned from the PostMovie() method returns a 201 status code. Updating a Record with the ASP.NET Web API Here’s how we can modify the Movie API controller to support updating an existing record. In this case, we need to create a PUT method to handle an HTTP PUT request: public void PutMovie(Movie movieToUpdate) { if (movieToUpdate.Id == 1) { // Update the movie in the database return; } // If you can't find the movie to update throw new HttpResponseException(HttpStatusCode.NotFound); } Unlike our PostMovie() method, the PutMovie() method does not return a result. The action either updates the database or, if the movie cannot be found, returns an HTTP Status code of 404. The following HTML page illustrates how you can invoke the PutMovie() method: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Put Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> var movieToUpdate = { id: 1, title: "The Hobbit", director: "Jackson" }; updateMovie(movieToUpdate, function () { alert("Movie updated!"); }); function updateMovie(movieToUpdate, callback) { $.ajax({ url: "/api/Movie", data: JSON.stringify(movieToUpdate), type: "PUT", contentType: "application/json;charset=utf-8", statusCode: { 200: function () { callback(); }, 404: function () { alert("Movie not found!"); } } }); } </script> </body> </html> Deleting a Record with the ASP.NET Web API Here’s the code for deleting a movie: public HttpResponseMessage DeleteMovie(int id) { // Delete the movie from the database // Return status code return new HttpResponseMessage(HttpStatusCode.NoContent); } This method simply deletes the movie (well, not really, but pretend that it does) and returns a No Content status code (204). The following page illustrates how you can invoke the DeleteMovie() action: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Delete Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> deleteMovie(1, function () { alert("Movie deleted!"); }); function deleteMovie(id, callback) { $.ajax({ url: "/api/Movie", data: JSON.stringify({id:id}), type: "DELETE", contentType: "application/json;charset=utf-8", statusCode: { 204: function () { callback(); } } }); } </script> </body> </html> Performing Validation How do you perform form validation when using the ASP.NET Web API? Because validation in ASP.NET MVC is driven by the Default Model Binder, and because the Web API uses the Default Model Binder, you get validation for free. Let’s modify our Movie class so it includes some of the standard validation attributes: using System.ComponentModel.DataAnnotations; namespace MyWebAPIApp.Models { public class Movie { public int Id { get; set; } [Required(ErrorMessage="Title is required!")] [StringLength(5, ErrorMessage="Title cannot be more than 5 characters!")] public string Title { get; set; } [Required(ErrorMessage="Director is required!")] public string Director { get; set; } } } In the code above, the Required validation attribute is used to make both the Title and Director properties required. The StringLength attribute is used to require the length of the movie title to be no more than 5 characters. Now let’s modify our PostMovie() action to validate a movie before adding the movie to the database: public HttpResponseMessage PostMovie(Movie movieToCreate) { // Validate movie if (!ModelState.IsValid) { var errors = new JsonArray(); foreach (var prop in ModelState.Values) { if (prop.Errors.Any()) { errors.Add(prop.Errors.First().ErrorMessage); } } return new HttpResponseMessage<JsonValue>(errors, HttpStatusCode.BadRequest); } // Add movieToCreate to the database and update primary key movieToCreate.Id = 23; // Build a response that contains the location of the new movie var response = new HttpResponseMessage<Movie>(movieToCreate, HttpStatusCode.Created); var relativePath = "/api/movie/" + movieToCreate.Id; response.Headers.Location = new Uri(Request.RequestUri, relativePath); return response; } If ModelState.IsValid has the value false then the errors in model state are copied to a new JSON array. Each property – such as the Title and Director property — can have multiple errors. In the code above, only the first error message is copied over. The JSON array is returned with a Bad Request status code (400 status code). The following HTML page illustrates how you can invoke our modified PostMovie() action and display any error messages: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Create Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> var movieToCreate = { title: "The Hobbit", director: "" }; createMovie(movieToCreate, function (newMovie) { alert("New movie created with an Id of " + newMovie.Id); }, function (errors) { var strErrors = ""; $.each(errors, function(index, err) { strErrors += "*" + err + "n"; }); alert(strErrors); } ); function createMovie(movieToCreate, success, fail) { $.ajax({ url: "/api/Movie", data: JSON.stringify(movieToCreate), type: "POST", contentType: "application/json;charset=utf-8", statusCode: { 201: function (newMovie) { success(newMovie); }, 400: function (xhr) { var errors = JSON.parse(xhr.responseText); fail(errors); } } }); } </script> </body> </html> The createMovie() function performs an Ajax request and handles either a 201 or a 400 status code from the response. If a 201 status code is returned then there were no validation errors and the new movie was created. If, on the other hand, a 400 status code is returned then there was a validation error. The validation errors are retrieved from the XmlHttpRequest responseText property. The error messages are displayed in an alert: (Please don’t use JavaScript alert dialogs to display validation errors, I just did it this way out of pure laziness) This validation code in our PostMovie() method is pretty generic. There is nothing specific about this code to the PostMovie() method. In the following video, Jon Galloway demonstrates how to create a global Validation filter which can be used with any API controller action: http://www.asp.net/web-api/overview/web-api-routing-and-actions/video-custom-validation His validation filter looks like this: using System.Json; using System.Linq; using System.Net; using System.Net.Http; using System.Web.Http.Controllers; using System.Web.Http.Filters; namespace MyWebAPIApp.Filters { public class ValidationActionFilter:ActionFilterAttribute { public override void OnActionExecuting(HttpActionContext actionContext) { var modelState = actionContext.ModelState; if (!modelState.IsValid) { dynamic errors = new JsonObject(); foreach (var key in modelState.Keys) { var state = modelState[key]; if (state.Errors.Any()) { errors[key] = state.Errors.First().ErrorMessage; } } actionContext.Response = new HttpResponseMessage<JsonValue>(errors, HttpStatusCode.BadRequest); } } } } And you can register the validation filter in the Application_Start() method in the Global.asax file like this: GlobalConfiguration.Configuration.Filters.Add(new ValidationActionFilter()); After you register the Validation filter, validation error messages are returned from any API controller action method automatically when validation fails. You don’t need to add any special logic to any of your API controller actions to take advantage of the filter. Querying using OData The OData protocol is an open protocol created by Microsoft which enables you to perform queries over the web. The official website for OData is located here: http://odata.org For example, here are some of the query options which you can use with OData: · $orderby – Enables you to retrieve results in a certain order. · $top – Enables you to retrieve a certain number of results. · $skip – Enables you to skip over a certain number of results (use with $top for paging). · $filter – Enables you to filter the results returned. The ASP.NET Web API supports a subset of the OData protocol. You can use all of the query options listed above when interacting with an API controller. The only requirement is that the API controller action returns its data as IQueryable. For example, the following Movie controller has an action named GetMovies() which returns an IQueryable of movies: public IQueryable<Movie> GetMovies() { return new List<Movie> { new Movie {Id=1, Title="Star Wars", Director="Lucas"}, new Movie {Id=2, Title="King Kong", Director="Jackson"}, new Movie {Id=3, Title="Willow", Director="Lucas"}, new Movie {Id=4, Title="Shrek", Director="Smith"}, new Movie {Id=5, Title="Memento", Director="Nolan"} }.AsQueryable(); } If you enter the following URL in your browser: /api/movie?$top=2&$orderby=Title Then you will limit the movies returned to the top 2 in order of the movie Title. You will get the following results: By using the $top option in combination with the $skip option, you can enable client-side paging. For example, you can use $top and $skip to page through thousands of products, 10 products at a time. The $filter query option is very powerful. You can use this option to filter the results from a query. Here are some examples: Return every movie directed by Lucas: /api/movie?$filter=Director eq ‘Lucas’ Return every movie which has a title which starts with ‘S’: /api/movie?$filter=startswith(Title,’S') Return every movie which has an Id greater than 2: /api/movie?$filter=Id gt 2 The complete documentation for the $filter option is located here: http://www.odata.org/developers/protocols/uri-conventions#FilterSystemQueryOption Summary The goal of this blog entry was to provide you with an overview of the new ASP.NET Web API introduced with the Beta release of ASP.NET 4. In this post, I discussed how you can retrieve, insert, update, and delete data by using jQuery with the Web API. I also discussed how you can use the standard validation attributes with the Web API. You learned how to return validation error messages to the client and display the error messages using jQuery. Finally, we briefly discussed how the ASP.NET Web API supports the OData protocol. For example, you learned how to filter records returned from an API controller action by using the $filter query option. I’m excited about the new Web API. This is a feature which I expect to use with almost every ASP.NET application which I build in the future.

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  • Passing Variables between views / view controllers

    - by Dan
    Hi I'm new to ObjectiveC / IPhoneSDK and I'm informally trying to study it on my own. What I'm basically trying to do is from one view there are 12 zodiac signs. When a user clicks one, it proceeds to the second view (with animation) and loads the name of the zodiac sign it clicked in a UILabel, that's it. Here are my codes: Lovescopes = 1st page Horoscopes = 2nd page Lovescopes4AppDelegate.h #import <UIKit/UIKit.h> #import "HoroscopesViewController.h" #import "Lovescopes4AppDelegate.h" @class Lovescopes4ViewController; @interface Lovescopes4AppDelegate : NSObject <UIApplicationDelegate> { UIWindow *window; Lovescopes4ViewController *viewController; HoroscopesViewController *horoscopesViewController; } -(void)loadHoroscope; -(void)loadMainPage; @property (nonatomic, retain) IBOutlet UIWindow *window; @property (nonatomic, retain) IBOutlet Lovescopes4ViewController *viewController; @property (nonatomic, retain) HoroscopesViewController *horoscopesViewController; @end Lovescopes4AppDelegate.m #import "Lovescopes4AppDelegate.h" #import "Lovescopes4ViewController.h" @implementation Lovescopes4AppDelegate @synthesize window; @synthesize viewController; @synthesize horoscopesViewController; -(void)loadHoroscope { HoroscopesViewController *aHoroscopeViewController = [[HoroscopesViewController alloc] initWithNibName:@"HoroscopesViewController" bundle:nil]; [self setHoroscopesViewController:aHoroscopeViewController]; [aHoroscopeViewController release]; [UIView beginAnimations:nil context:NULL]; [UIView setAnimationDuration:0.5]; [UIView setAnimationTransition:UIViewAnimationTransitionFlipFromLeft forView:window cache:YES]; [viewController.view removeFromSuperview]; [self.window addSubview:[horoscopesViewController view]]; [UIView commitAnimations]; } -(void)loadMainPage { [UIView beginAnimations:nil context:NULL]; [UIView setAnimationDuration:0.5]; [UIView setAnimationTransition:UIViewAnimationTransitionFlipFromRight forView:window cache:NO]; [horoscopesViewController.view removeFromSuperview]; [self.window addSubview:[viewController view]]; [UIView commitAnimations]; [horoscopesViewController release]; horoscopesViewController = nil; } - (void)applicationDidFinishLaunching:(UIApplication *)application { // Override point for customization after app launch [window addSubview:viewController.view]; [window makeKeyAndVisible]; } - (void)dealloc { [viewController release]; [window release]; [super dealloc]; } @end Lovescopes4ViewController.h #import <UIKit/UIKit.h> #import "HoroscopesViewController.h" @interface Lovescopes4ViewController : UIViewController { HoroscopesViewController *hvc; } -(IBAction)loadAries; @property (nonatomic, retain) HoroscopesViewController *hvc; @end Lovescope4ViewController.m #import "Lovescopes4ViewController.h" #import "Lovescopes4AppDelegate.h" @implementation Lovescopes4ViewController @synthesize hvc; -(IBAction)loadAries { NSString *selected =@"Aries"; [hvc loadZodiac:selected]; Lovescopes4AppDelegate *mainDelegate = (Lovescopes4AppDelegate *) [[UIApplication sharedApplication] delegate]; [mainDelegate loadHoroscope]; } HoroscopesViewController.h #import <UIKit/UIKit.h> @interface HoroscopesViewController : UIViewController { IBOutlet UILabel *zodiacLabel; } -(void)loadZodiac:(id)zodiacSign; -(IBAction)back; @property (nonatomic, retain) IBOutlet UILabel *zodiacLabel; @end HoroscopesViewController.m #import "HoroscopesViewController.h" #import "Lovescopes4AppDelegate.h" @implementation HoroscopesViewController @synthesize zodiacLabel; /* // The designated initializer. Override if you create the controller programmatically and want to perform customization that is not appropriate for viewDidLoad. - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil { if (self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]) { // Custom initialization } return self; } */ /* // Implement viewDidLoad to do additional setup after loading the view, typically from a nib. - (void)viewDidLoad { [super viewDidLoad]; } */ /* // Override to allow orientations other than the default portrait orientation. - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation { // Return YES for supported orientations return (interfaceOrientation == UIInterfaceOrientationPortrait); } */ -(void)loadZodiac:(id)zodiacSign { zodiacLabel.text = [NSString stringWithFormat: @"%@", zodiacSign]; } -(IBAction)back { Lovescopes4AppDelegate *mainDelegate = (Lovescopes4AppDelegate *) [[UIApplication sharedApplication] delegate]; [mainDelegate loadMainPage]; }

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  • Cant bind data to a table view

    - by sudhakarilla
    Hi, I have retrieved data from Json URL and displayed it in a table view. I have also inlcuced a button in table view. On clicking the button the data must be transferred to a another table view. The problem is that i could send the data to a view and could display it on a label. But i couldnt bind the dat to table view ... Here's some of the code snippets... Buy Button... -(IBAction)Buybutton{ /* UIAlertView *alert =[[UIAlertView alloc]initWithTitle:@"thank u" message:@"products" delegate:nil cancelButtonTitle:@"ok" otherButtonTitles:nil]; [alert show]; [alert release];*/ Product *selectedProduct = [[data products]objectAtIndex:0]; CartViewController *cartviewcontroller = [[[CartViewController alloc] initWithNibName:@"CartViewController" bundle:nil]autorelease]; cartviewcontroller.product= selectedProduct; //NSString *productname=[product ProductName]; //[currentproducts setproduct:productname]; [self.view addSubview:cartviewcontroller.view]; } CartView... // Implement viewDidLoad to do additional setup after loading the view, typically from a nib. - (void)viewDidLoad { [super viewDidLoad]; data = [GlobalData SharedData]; NSMutableArray *prod =[[NSMutableArray alloc]init]; prod = [data products]; for(NSDictionary *product in prod) { Cart *myprod = [[Cart alloc]init]; myprod.Description = [product Description]; myprod.ProductImage =[product ProductImage]; myprod.ProductName = [product ProductName]; myprod.SalePrice = [product SalePrice]; [data.carts addObject:myprod]; [myprod release]; } Cart *cart = [[data carts]objectAtIndex:0]; NSString *productname=[cart ProductName]; self.label.text =productname; NSLog(@"carts"); } (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { return 1; } (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { return [data.carts count]; } -(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath { return 75; } (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { NSLog(@"cellforrow"); static NSString *CellIdentifier = @"Cell"; ProductCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; if(cell ==nil) { cell = [[[ProductCell alloc]initWithFrame:CGRectZero reuseIdentifier:CellIdentifier]autorelease]; } NSUInteger row = [indexPath row]; Cart *cart = [[data carts]objectAtIndex:row]; cell.productNameLabel.text = [cart ProductName]; /*NSString *sale = [[NSString alloc]initWithFormat:@"SalePrice:%@",[cart SalePrice]]; cell.salePriceLabel.text = sale; cell.DescriptionLabel.text = [cart Description]; NSMutableString imageUrl =[NSMutableString string]; [imageUrl appendFormat:@"http://demo.s2commerce.net/DesktopModules/S2Commerce/Images/Products/%@",[product ProductImage]]; NSLog(@"imageurl:%@",imageUrl); NSString mapURL = [imageUrl stringByReplacingPercentEscapesUsingEncoding:NSASCIIStringEncoding]; NSData* imageData = [[NSData alloc]initWithContentsOfURL:[NSURL URLWithString:mapURL]]; UIImage* image = [[UIImage alloc]initWithData:imageData]; cell.productImageview.image = image; [imageData release]; [image release];*/ return cell; } I am also getting the following error in the console 2010-06-11 18:34:29.169 navigation[4109:207] * -[CartViewController tableView:numberOfRowsInSection:]: message sent to deallocated instance 0xcb4d4f90

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  • making an array controller the target of a button

    - by ian
    I am working through a chapter of COCOA PROGRAMMING FOR MAC OS X (3RD EDITION) on NSArrayController and it tells me to: Control-Drag to make the array controller become the target of the Add New Employee button. Set the action to add: However when I drag over the array controller it does not highlight so I get no target options. How do I do this correctly in the new XCode full size image document.h: // // Document.h // RaiseMan // // Created by user on 11/12/11. // Copyright (c) 2011 __MyCompanyName__. All rights reserved. // #import <Cocoa/Cocoa.h> @interface Document : NSDocument { NSMutableArray *employees; } @end document.m: // // Document.m // RaiseMan // // Created by user on 11/12/11. // Copyright (c) 2011 __MyCompanyName__. All rights reserved. // #import "Document.h" @implementation Document - (id)init { self = [super init]; if (self) { employees = [[NSMutableArray alloc] init]; } return self; } - (void)dealloc { [self setEmployees:nil]; [super dealloc]; } -(void)setEmployees:(NSMutableArray *)a { //this is an unusual setter method we are goign to ad a lot of smarts in the next chapter if (a == employees) return; [a retain]; [employees release]; employees = a; } - (NSString *)windowNibName { // Override returning the nib file name of the document // If you need to use a subclass of NSWindowController or if your document supports multiple NSWindowControllers, you should remove this method and override -makeWindowControllers instead. return @"Document"; } - (void)windowControllerDidLoadNib:(NSWindowController *)aController { [super windowControllerDidLoadNib:aController]; // Add any code here that needs to be executed once the windowController has loaded the document's window. } - (NSData *)dataOfType:(NSString *)typeName error:(NSError **)outError { /* Insert code here to write your document to data of the specified type. If outError != NULL, ensure that you create and set an appropriate error when returning nil. You can also choose to override -fileWrapperOfType:error:, -writeToURL:ofType:error:, or -writeToURL:ofType:forSaveOperation:originalContentsURL:error: instead. */ NSException *exception = [NSException exceptionWithName:@"UnimplementedMethod" reason:[NSString stringWithFormat:@"%@ is unimplemented", NSStringFromSelector(_cmd)] userInfo:nil]; @throw exception; return nil; } - (BOOL)readFromData:(NSData *)data ofType:(NSString *)typeName error:(NSError **)outError { /* Insert code here to read your document from the given data of the specified type. If outError != NULL, ensure that you create and set an appropriate error when returning NO. You can also choose to override -readFromFileWrapper:ofType:error: or -readFromURL:ofType:error: instead. If you override either of these, you should also override -isEntireFileLoaded to return NO if the contents are lazily loaded. */ NSException *exception = [NSException exceptionWithName:@"UnimplementedMethod" reason:[NSString stringWithFormat:@"%@ is unimplemented", NSStringFromSelector(_cmd)] userInfo:nil]; @throw exception; return YES; } + (BOOL)autosavesInPlace { return YES; } - (void)setEmployees:(NSMutableArray *)a; @end person.h: // // Person.h // RaiseMan // // Created by user on 11/12/11. // Copyright (c) 2011 __MyCompanyName__. All rights reserved. // #import <Foundation/Foundation.h> @interface Person : NSObject { NSString *personName; float expectedRaise; } @property (readwrite, copy) NSString *personName; @property (readwrite) float expectedRaise; @end person.m: // // Person.m // RaiseMan // // Created by user on 11/12/11. // Copyright (c) 2011 __MyCompanyName__. All rights reserved. // #import "Person.h" @implementation Person - (id) init { self = [super init]; expectedRaise = 5.0; personName = @"New Person"; return self; } - (void)dealloc { [personName release]; [super dealloc]; } @synthesize personName; @synthesize expectedRaise; @end

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  • Codeigniter: Controller URI with Library

    - by Kevin Brown
    I have a working controller and library function, but I now need to pass a URI segment to the library for decision making, and I'm stuck. Controller: function survey($method) { $id = $this->session->userdata('id'); $data['member'] = $this->home_model->getUser($id); //Convert the db Object to a row array $data['manager'] = $data['member']->row(); $manager_id = $data['manager']->manager_id; $data['manager'] = $this->home_model->getUser($manager_id); $data['manager'] = $data['manager']->row(); if ($data['manager']->credits == '0') { flashMsg('warning',"You can't complete the assessment until your manager has purchased credit."); redirect('home','location'); } elseif ($data['manager']->test_complete == '3'){ flashMsg('warning',"You already completed the Assessment."); redirect('home','location'); } else{ $data['header'] = "Home"; $this->survey_form_processing->survey_form($this->_container,$data); } } Library: function survey_form($container) { if($method ==1){ $id = $this->CI->session->userdata('id'); // Setup fields for($i=1;$i<18;$i++){ $fields["a_".$i] = 'Question '.$i; } for($i=1;$i<17;$i++){ $fields["b_".$i] = 'Question '.$i; } $fields["company_name"] = "Company Name"; $fields['company_address'] = "company_address"; $fields['company_phone'] = "company_phone"; $fields['company_state'] = "company_state"; $fields['company_city'] = "company_city"; $fields['company_zip'] = "company_zip"; $fields['job_title'] = "job_title"; $fields['job_type'] = "job_type"; $fields['job_time'] = "job_time"; $fields['department'] = "department"; $fields['supervisor'] = "supervisor"; $fields['vision'] = "vision"; $fields['height'] = "height"; $fields['weight'] = "weight"; $fields['hand_dominance'] = "hand_dominance"; $fields['areas_of_fatigue'] = "areas_of_fatigue"; $fields['injury_review'] = "injury_review"; $fields['job_positive'] = "job_positive"; $fields['risk_factors'] = "risk_factors"; $fields['job_improvement_short'] = "job_improvement_short"; $fields['job_improvement_long'] = "job_improvement_long"; $fields["c_1"] = "Near Lift"; $fields["c_2"] = "Middle Lift"; $fields["c_3"] = "Far Lift"; $this->CI->validation->set_fields($fields); // Set Rules for($i=1;$i<18;$i++){ $rules["a_".$i]= 'hour|integer|max_length[2]'; } for($i=1;$i<17;$i++){ $rules["b_".$i]= 'hour|integer|max_length[2]'; } // Setup form default values $this->CI->validation->set_rules($rules); if ( $this->CI->validation->run() === FALSE ) { // Output any errors $this->CI->validation->output_errors(); } else { // Submit form $this->_submit(); } // Modify form, first load $this->CI->db->from('be_user_profiles'); $this->CI->db->where('user_id' , $id); $user = $this->CI->db->get(); $this->CI->db->from('be_survey'); $this->CI->db->where('user_id' , $id); $survey = $this->CI->db->get(); $user = array_merge($user->row_array(),$survey->row_array()); $this->CI->validation->set_default_value($user); // Display page $data['user'] = $user; $data['header'] = 'Risk Assessment Survey'; $data['page'] = $this->CI->config->item('backendpro_template_public') . 'form_survey'; $this->CI->load->view($container,$data); } else{ redirect('home','location'); } } My library function doesn't know what to do with Method...and I'm confused. Does it have something to do with instances in my library?

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  • Generating alerts from ossec ( server- agent ) model

    - by batman
    I'm very new to OSSEC. I use a server-agent model. I wish to generate alert for the following actions ( in agent side ): 1) Sample Alert for delation of logs I added the rules for these in agent's ossec.conf using <localfile> tags. Like this : <localfile> <log_format>syslog</log_format> <location>/var/log/syslog</location> </localfile> In my server's ossec.conf. I added the following : <global> <email_notification>yes</email_notification> <email_to>xxxx@xxxxxx</email_to> <smtp_server>smtp.gmail.com</smtp_server> <email_from>xxxx@xxx</email_from> </global> And I restarted my server. Now I tried to delete the agents syslog file using rm syslog. But no alerts has been triggered. Where I'm making the mistake?

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  • Calling ASP.NET MVC Controller explicitly via AJAX

    - by effkay
    I know that I can use following piece of code to refresh a div: <%=Ajax.ActionLink( "Update", "Administration", new AjaxOptions { UpdateTargetId = "grid", LoadingElementId = "grid-wait" } ) %> But this creates a link; user will have to click on it to get the view refreshed. How can I make it automatic, i.e., like say if I want the grid to be refreshed after every five seconds?

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  • Avoiding .gsp extention in a GSP Page Without a Controller

    - by Guy
    Using grails 1.2.1 this should be very simple, but still I can't get it to work. In my application /grails-app/views I've added mypage.gsp Plus "/mypage"(view:"mypage") to the mappings block of my URLMapping class. while http://server-name:8080/myapp/mypage.gsp works I'm still getting 404 - page not found when I try to open http://server-name:8080/myapp/mypage Thanks, Guy

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  • iphone - UIViewController header view errors

    - by Fiona
    Hi there, So to give a little background: I've an app that has a UITableViewController- (ContactDetailViewController) In this view at the top, I require a few labels and buttons, followed by a group style tableview. So I've created a nib file containing these elements. (ContactHeaderView.xib) Then in the viewDidLoad of ContactDetailViewController I've loaded this nib as the headerView. See implementation file below: #import "ContactDetailViewController.h" #import "DisplayInfoViewController.h" #import "ActionViewController.h" @implementation ContactDetailViewController @synthesize name; @synthesize date; @synthesize nextAction; @synthesize nameLabel; @synthesize usernameLabel; @synthesize nextActionTextField; @synthesize dateLabel; @synthesize contactInfoButton; @synthesize backgroundInfoButton; @synthesize actionDoneButton; - (void)viewDidLoad { [super viewDidLoad]; } - (void)didReceiveMemoryWarning { // Releases the view if it doesn't have a superview. [super didReceiveMemoryWarning]; // Release any cached data, images, etc that aren't in use. } - (void)viewDidUnload { // Release any retained subviews of the main view. // e.g. self.myOutlet = nil; } #pragma mark Table view methods - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { return 1; } // Customize the number of rows in the table view. - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { return 3; } - (UIView *) tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section { if (section == 0){ UIViewController *chv = [[[UIViewController alloc] initWithNibName:@"ContactHeaderView" bundle:nil] autorelease]; // self.nameLabel.text = self.name; return chv.view; }else{ return nil; } } - (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section{ return 300.0; } // Customize the appearance of table view cells. - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @"Cell"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease]; } // Set up the cell... return cell; } - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { // Navigation logic may go here. Create and push another view controller. // AnotherViewController *anotherViewController = [[AnotherViewController alloc] initWithNibName:@"AnotherView" bundle:nil]; // [self.navigationController pushViewController:anotherViewController]; // [anotherViewController release]; } /* // Override to support conditional editing of the table view. - (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath { // Return NO if you do not want the specified item to be editable. return YES; } */ - (void)dealloc { [name release]; [date release]; [nextAction release]; [nameLabel release]; [usernameLabel release]; [nextActionTextField release]; [dateLabel release]; [contactInfoButton release]; [backgroundInfoButton release]; [actionDoneButton release]; [super dealloc]; } -(IBAction)displayContactInfo:(id)sender{ DisplayInfoViewController *divc = [[DisplayInfoViewController alloc] init]; divc.textView = self.nextAction; divc.title = @"Contact Info"; [self.navigationController pushViewController:divc animated:YES]; [divc release]; } -(IBAction)displayBackgroundInfo:(id)sender{ DisplayInfoViewController *divc = [[DisplayInfoViewController alloc] init]; divc.textView = self.nextAction; divc.title = @"Background Info"; [self.navigationController pushViewController:divc animated:YES]; [divc release]; } -(IBAction)actionDone:(id)sender{ ActionViewController *avc = [[ActionViewController alloc] init]; avc.title = @"Action"; avc.nextAction = self.nextAction; [self.navigationController pushViewController:avc animated:YES]; [avc release]; } @end Here's the Header File: #import <UIKit/UIKit.h> @interface ContactDetailViewController : UITableViewController { NSString *name; NSString *date; NSString *nextAction; IBOutlet UILabel *nameLabel; IBOutlet UILabel *usernameLabel; IBOutlet UITextField *nextActionTextField; IBOutlet UILabel *dateLabel; IBOutlet UIButton *contactInfoButton; IBOutlet UIButton *backgroundInfoButton; IBOutlet UIButton *actionDoneButton; } @property (nonatomic, retain) NSString *name; @property (nonatomic, retain) NSString *date; @property (nonatomic, retain) NSString *nextAction; @property (nonatomic, retain) IBOutlet UILabel *nameLabel; @property (nonatomic, retain) IBOutlet UILabel *usernameLabel; @property (nonatomic, retain) IBOutlet UITextField *nextActionTextField; @property (nonatomic, retain) IBOutlet UILabel *dateLabel; @property (nonatomic, retain) IBOutlet UIButton *contactInfoButton; @property (nonatomic, retain) IBOutlet UIButton *backgroundInfoButton; @property (nonatomic, retain) IBOutlet UIButton *actionDoneButton; -(IBAction)displayContactInfo: (id)sender; -(IBAction)displayBackgroundInfo: (id)sender; -(IBAction)actionDone: (id)sender; @end However when I run it, I get the following error message: * Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[ setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key nameLabel.' In IB I've hooked up the labels/buttons/textbox to the File's Owner (set the File's Owner Class to: ContactDetailViewController) Anyone any idea what I'm doing wrong? Regards, Fiona

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  • Back button title not receiving previous view controller's title

    - by Prasanna
    I am pushing 2 view controllers in to navigation stack in ApplicationDidFinishLaunching. [navigationController pushViewController:favorites animated:NO]; [navigationController pushViewController:root animated:NO]; The app loads fine, but on the start screen, the back button title is simply "Back". I do have a title for the FavoritesViewController, and a navigationItem title setup to Favorites. Am I missing something? Appreciate your help.

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