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  • Custom constructors for models in Google App Engine (python)

    - by Nikhil Chelliah
    I'm getting back to programming for Google App Engine and I've found, in old, unused code, instances in which I wrote constructors for models. It seems like a good idea, but there's no mention of it online and I can't test to see if it works. Here's a contrived example, with no error-checking, etc.: class Dog(db.Model): name = db.StringProperty(required=True) breeds = db.StringListProperty() age = db.IntegerProperty(default=0) def __init__(self, name, breed_list, **kwargs): db.Model.__init__(**kwargs) self.name = name self.breeds = breed_list.split() rufus = Dog('Rufus', 'spaniel terrier labrador') rufus.put() The **kwargs are passed on to the Model constructor in case the model is constructed with a specified parent or key_name, or in case other properties (like age) are specified. This constructor differs from the default in that it requires that a name and breed_list be specified (although it can't ensure that they're strings), and it parses breed_list in a way that the default constructor could not. Is this a legitimate form of instantiation, or should I just use functions or static/class methods? And if it works, why aren't custom constructors used more often?

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  • What is the MVC version of this code?

    - by Ian Boyd
    i'm trying to wrap my head around how to enterprise up my code: taking a simple routine and splitting it up into 5 or 6 methods in 3 or 4 classes. i quickly came up three simple examples of code how i currently write it. Could someone please convert these into an MVC/MVP obfuscated version? Example 1: The last name is mandatory. Color the text box red if nothing is entered. Color it green if stuff is entered: private void txtLastname_TextChanged(object sender, EventArgs e) { //Lastname mandatory. //Color pinkish if nothing entered. Greenish if entered. if (txtLastname.Text.Trim() == "") { //Lastname is required, color pinkish txtLastname.BackColor = ControlBad; } else { //Lastname entered, remove the coloring txtLastname.BackColor = ControlGood; } } Example 2: The first name is optional, but try to get it. We'll add a bluish tint to this "try to get" field: private void txtFirstname_TextChanged(object sender, EventArgs e) { //Firstname can be blank. //Hint them that they should *try* to get it with a bluish color. //If they do enter stuff: it better be not all spaces. if (txtFirstname.Text == "") { //Nothing there, hint it blue txtFirstname.BackColor = ControlRequired; } else if (txtFirstname.Text.Trim() == "") { //They entered spaces - bad user! txtFirstname.BackColor = ControlBad; } else { //Entered stuff, remove coloring txtFirstname.BackColor = SystemColors.Window; } } Example 3 The age is totally optional. If an age is entered, it better be valid: private void txtAge_TextChanged(object sender, EventArgs e) { //Age is optional, but if entered it better be valid int nAge = 0; if (Int32.TryParse(txtAge.Text, out nAge)) { //Valid integer entered if (nAge < 0) { //Negative age? i don't think so txtAge.BackColor = ControlBad; } else { //Valid age entered, remove coloring txtAge.BackColor = SystemColors.Window; } } else { //Whatever is in there: it's *not* a valid integer, if (txtAge.Text == "") { //Blank is okay txtAge.BackColor = SystemColors.Window; } else { //Not a valid age, bad user txtAge.BackColor = ControlBad; } } } Every time i see MVC code, it looks almost like random splitting of code into different methods, classes, and files. i've not been able to determine a reason or pattern to their madness. Without any understanding of they why it's being one some way, it makes no sense. And using the words model, view, controller and presenter, like i'm supposed to know what that means, doesn't help. The model is your data. The view shows data on screen. The controller is used to carry out the users actions And oranges taste orangy. Here's my attempt at splitting things up in order to make the code more difficult to follow. Is this anywhere close to MVC? private void txtFirstname_TextChanged(object sender, EventArgs e) { FirstnameTextChangedHandler(sender, e); } private void FirstnameTextChangedHandler(sender, e) { string firstname = GetFirstname(); Color firstnameTextBoxColor = GetFirstnameTextBoxColor(firstname); SetFirstNameTextBoxColor(firstnameTextBoxColor); } private string GetFirstname() { return txtFirstname.Text; } private Color GetFirstnameTextBoxColor(string firstname) { //Firstname can be blank. //Hint them that they should *try* to get it with a bluish color. //If they do enter stuff: it better be not all spaces. if (firstname == "") { //Nothing there, hint it blue return GetControlRequiredColor(); } else if (firstname.Trim() == "") { //They entered spaces - bad user! return GetControlBadColor(); } else { //Entered stuff, remove coloring return GetControlDefaultColor(); } } private Color GetControlRequiredColor() { return ControlRequired; } private Color GetControlBadColor() { return ControlBad; } private Color GetControlGoodColor() { return ControlGood; } //am i doin it rite i've obfuscated the code, but it's still altogether. The next step in the MVC obfuscation, i gather, is to hide the code in 3 or 4 different files. It's that next step that i don't understand. What is the logical separation of which functions are moved into what other classes? Can someone translate my 3 simple examples above into full fledged MVC obfuscation? Edit: Not ASP/ASP.NET/Online. Pretend it's on a desktop, handheld, surface, kiosk. And pretend it's language agnostic.

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  • How can I add an event handler to an event by name?

    - by cyclotis04
    I'm attempting to add an event handler for every control on my form. The form is a simple info box which pops up, and clicking anywhere on it does the same thing (sort of like Outlook's email notifier.) To do this, I've written a recursive method to add a MouseClick handler to each control, as follows: private void AddMouseClickHandler(Control control, MouseEventHandler handler) { control.MouseClick += handler; foreach (Control subControl in control.Controls) AddMouseClickHandler(subControl, handler); } However, if I wanted to add a handler for all of the MouseDown and MouseUp events, I'd have to write two more methods. I'm sure there's a way around this, but I can't find it. I want a method like: private void AddRecursiveHandler(Control control, Event event, EventHandler handler) { control.event += handler; foreach (Control subControl in control.Controls) AddRecursiveHandler(subControl, event, handler); }

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  • Using scanf() in C++ programs is faster than using cin ?

    - by zeroDivisible
    Hello, I don't know if this is true, but when I was reading FAQ on one of the problem providing sites, I found something, that poke my attention: Check your input/output methods. In C++, using cin and cout is too slow. Use these, and you will guarantee not being able to solve any problem with a decent amount of input or output. Use printf and scanf instead. Can someone please clarify this? Is really using scanf() in C++ programs faster than using cin something ? If yes, that is it a good practice to use it in C++ programs? I thought that it was C specific, though I am just learning C++...

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  • Writing Resources from filesystem in Android

    - by Markus
    Hi, as I need to get a specific Frame from a Website I want to display in an WebView, I decided to grab the .html from the net and save it under file:///data/data//files/file.html. Stroed there I can edit it using regex or String methods. Now two questions: Is there a way to bind this file to an resource. e.g. to /res/raw/file.html and get it updated dynamically as i edit it? Or can i write the File directly to the resources? Is this whole stuff I do there any good or performant at all? I mean maybe there is a better way to get the .html code between two tags from a Webpage and display it via WebView. Kind regards Markus

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  • Simplest way to extend doctrine for MVC Models

    - by RobertPitt
    Im developing my own framework that uses namespaces. Doctrine is already integrated into my auto loading system and im now at the stage where ill be creating the model system for my application Usually i would create a simple model like so: namespace Application\Models; class Users extends \Framework\Models\Database{} which would inherit all the default database model methods, But with Doctrine im still learning how it all works, as its not just a simple DBAL. I need to understand whats the part of doctrine my classes would extend where i can do the following: namespace Application\Models; class Users Extends Doctrine\Something\Table { public $__table_name = "users"; } And thus within the controller i would be able to do the following: public function Display($uid) { $User = $this->Model->Users->findOne(array("id" => (int)$id)); } Anyone help me get my head around this ?

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  • Want to understand C++ sentry object

    - by Romain Hippeau
    I answered this [question][1] and somebody else had answered as he modern C++ equivalent would be a sentry object: construct it at the beginning of a function, with its constructor implementing call(), and upon return (or abnormal exit), its destructor implements I am not familiar with using sentry objects in C++. I thought they were limited to input and output streams. Could somebody explain to me about C++ sentry objects as well as how to use them as an around interceptor for one or more methods in a class ? [1]: http://stackoverflow.com/questions/2688043/call-return-feature-of-classic-cc-with-classes-what-modern-languages-have-it/2688095#2688095 /

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  • In a binary search Tree

    - by user1044800
    In a binary search tree that takes a simple object.....when creating the getter and setter methods for the left, right, and parent. do I a do a null pointer? as in this=this or do I create the object in each method? Code bellow... This is my code: public void setParent(Person parent) { parent = new Person( parent.getName(), parent.getWeight()); //or is the parent supposed to be a null pointer ???? This is the code it came from: public void setParent(Node parent) { this.parent = parent; } Their code takes a node from the node class...my set parent is taking a person object from my person class.....

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  • Python unittest with expensive setup

    - by Staale
    My test file is basically: class Test(unittest.TestCase): def testOk(): pass if __name__ == "__main__": expensiveSetup() try: unittest.main() finally: cleanUp() However, I do wish to run my test through Netbeans testing tools, and to do that I need unittests that don't rely on an environment setup done in main. Looking at http://stackoverflow.com/questions/402483/caching-result-of-setup-using-python-unittest - it recommends using Nose. However, I don't think Netbeans supports this. I didn't find any information indicating that it does. Additionally, I am the only one here actually writing tests, so I don't want to introduce additional dependencies for the other 2 developers unless they are needed. How can I do the setup and cleanup once for all the tests in my TestSuite? The expensive setup here is creating some files with dummy data, as well as setting up and tearing down a simple xml-rpc server. I also have 2 test classes, one testing locally and one testing all methods over xml-rpc.

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  • Casting objects to Integer,string ,...

    - by Milan
    Hello everybody! I have one small problem. I have list of types(int,string,..) ArrayList<Class> typeList; and I have some input values; ArrayList<Object> values; How to cast some value to some type if I know which type from the typeList is the values; typeList.get(i).cast(values.get(i)); <- this is not working??? Actualy I generate dynamic form in runtime. With Java reflection I get parameterTypes from methods from some class, I generate form with input fields and then i want to cast the text from the input fields to specific types from the paramterTypes that I got with Java reflection from some class.

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  • pluralize and singularize for spanish language

    - by el_quick
    Hello, sorry for my english... I have a rails application developed to spain, therefore, all content is in spanish, so, I have a search box to search in a mysql database, all rows are in spanish, I'd like to improve my search to allow to users to search keywords in singular or plural form, for example: keyword: patatas found: patata keyword: veces found: vez keyword: vez found: veces keyword: actividades found: actividad In english, this could be relatively easy with help of singularize and pluralize methods ... where `searching_field` like '%singularized_keyword%' or `searching_field` like '%pluralized_keyword%' But, for spanish.... Some help? Thanks!

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  • Seam + hibernate + jsf on weblogic

    - by Kiva
    I'm making a little project with Seam, Hibernate and JSF. This project run on JBoss 5.1. My boss wants to deploy this project on WebLogic. I read on the seam documentation that seam and WebLogic don't work fine together. I would like to know if I can use Hibernate (with JPA) and JSF on WebLogic and what framework (struts, spring?) I can use to replace Seam. Edit: I read in the seam documentation (chapter 39, weblogic integration) and I find that: For several releases of Weblogic there has been an issue with how Weblogic generates stubs and compiles EJB's that use variable arguments in their methods. This is confirmed in the Weblogic 9.X and 10.0.MP1 versions. Unfortunately the 10.3 version only partially addresses the issue as detailed below. So, I want to know if other problems like this exist. Edit 2: I use Weblogic 10.3

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  • Console App Mouse-Click X Y Coordinate Detection/Comparison

    - by Bloodyaugust
    I have a game that I am working on in a C# console application, purely as practice before going on to better methods. As opposed to using something such as a Windows Forms App, which has button functionality built in, I am endeavoring to grab the cursor position (which I know how to do) and compare it to a number of area's inside a console application as defined by perhaps pixel location, but I also do not know if there is some sort of built in unit of space other than pixels (this last bit is the part I am unable to figure). P.S. I know this is in general terms, with no code already provided, but I do not feel that it is needed as all I am asking for is a brief explanation of how to grab X Y coordinates inside a console application, and stick them in int variables. Many Thanks in advance! :D

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  • .net, C# Interface between Business Logic and DAL

    - by Joel
    I'm working on a small application from scratch and using it to try to teach myself architecture and design concepts. It's a .NET 3.5, WPF application, and I'm using Sql Compact Edition as my data store. I'm working on the business logic layer, and have just now begun to write the DAL. I'm just using SqlCeComamnds to send over simple queries and SqlCeResultSet to get at the results. I'm starting to design my Insert and Update methods, and here's the issue - I don't know the best way to get the necessary data from the BLL into the DAL. Do I pass in a generic collection? Do I have a massive parameter list with all the data for the database? Do I simply pass in the actual business object (thus tying my DAL to the conrete stuff in the BLL?). I thought about using interfaces - simply passing IBusinessObjectA into the DAL, which provides the simplicity I'm looking for without tying me TOO tightly to current implementations. What do you guys think?

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  • Securing an ajax request

    - by asdasdsa
    i have a website that uses session cookies for security. it works fine and all, but any ajax requests right now are not secure. example being lets say a user is on a page. they can only get to this page if they are logged in with a session - so far so good. but now the ajax request they ask for is ajaxpages/somepage.php?somevar=something&anothervar=something if any other user decides to just go to that link themselves (without a session) they still get the same ajax output that was meant for logged in people. so obviously im going to have to pass session data across when i send an ajax request. anyone have any tips for the best way of doing this? ive never done this before and would rather use trusted methods than make up my own.

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  • Nonstatic conversion functions; Casting different types, e.g. DirectX vector to OpenGL vector

    - by Markus
    I am currently working on a game "engine" that needs to move values between a 3D engine, a physics engine and a scripting language. Since I need to apply vectors from the physics engine to 3D objects very often and want to be able to control both the 3D, as well as the physics objects through the scripting system, I need a mechanism to convert a vector of one type (e.g. vector3d<float>) to a vector of the other type (e.g. btVector3). Unfortunately I can make no assumptions on how the classes/structs are laid out, so a simple reinterpret_cast probably won't do. So the question is: Is there some sort of 'static'/non-member casting method to achieve basically this: vector3d<float> operator vector3d<float>(btVector3 vector) { // convert and return } btVector3 operator btVector3(vector3d<float> vector) { // convert and return } Right now this won't compile since casting operators need to be member methods. (error C2801: 'operator foo' must be a non-static member)

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  • How do I combine similar method calls into a delegate pattern?

    - by Daniel T.
    I have three methods: public void Save<T>(T entity) { using (new Transaction()) { Session.Save(entity); } } public void Create<T>(T entity) { using (new Transaction()) { Session.Create(entity); } } public void Delete<T>(T entity) { using (new Transaction()) { Session.Delete(entity); } } As you can see, the only thing that differs is the method call inside the using block. How can I rewrite this so it's something like this instead: public void Save<T>(T entity) { TransactionWrapper(Session.Save(entity)); } public void Create<T>(T entity) { TransactionWrapper(Session.Create(entity)); } public void Save<T>(T entity) { TransactionWrapper(Session.Save(entity)); } So in other words, I pass a method call as a parameter, and the TransactionWrapper method wraps a transaction around the method call.

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  • What's an easy way of storing an array of numbers in Javascript that I can add/remove from?

    - by SLC
    In C# I would create a List then I could add and remove numbers very easily. Does identical functionality exist in Javascript, or do I have to write my own methods to search and remove items using a loop? var NumberList = []; NumberList.Add(17); NumberList.Add(25); NumberList.Remove(17); etc. I know I can use .push to add a number, so I guess it's really how to remove an individual number without using a loop that I'm looking for. edit: of course, if there's no other way then I'll use a loop!:)

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  • Task.wait not working as I imagined

    - by user2357446
    I am trying to download a file, wait for the file to finish downloading, and then read the file afterwards. I have the following methods to do this: private async Task startDownload(string link, string savePath) { WebClient client = new WebClient(); client.DownloadProgressChanged += new DownloadProgressChangedEventHandler(client_DownloadProgressChanged); client.DownloadFileCompleted += new AsyncCompletedEventHandler(client_DownloadFileCompleted); await client.DownloadFileTaskAsync(new Uri(link), savePath); } private void checkUpdateButton_Click(object sender, EventArgs e) { Task task = Task.Factory.StartNew(() => startDownload(versionLink, versionSaveTo)); task.Wait(); if (task.IsCompleted) { checkVersion(); } } The checkVersion() method reads the file that was downloaded. This is throwing an IOException saying that the file is in use by something else and cannot be read. I thought that having task.Wait would prevent the rest of the method from executing until the task was finished?

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  • Linq Query to IEnumerable<T> Extension Method

    - by CSharpNoob
    Consider this, class Item { public string ID { get; set;} public string Description { get; set; } } class SaleItem { public string ID { get; set;} public string Discount { get; set; } } var itemsToRemoved = (List<Item>)ViewState["ItemsToRemove"]; // get only rows of ID var query = from i in itemsToRemoved select i.ID; var saleItems= (List<SaleItem>)ViewState["SaleItems"]; foreach (string s in query.ToArray()) { saleItems.RemoveItem(s); } How can I write this LINQ phrase using IEnumerable/List Extension methods // get only rows of ID var query = from i in items select i.ID; thanks in advance.

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  • How to modify posted form data within controller action before sending to view?

    - by Gary
    I want to render the same view after a successful action (rather than use RedirectToAction), but I need to modify the model data that is rendered to that view. The following is a contrived example that demonstrates two methods that that do not work: [AcceptVerbs("POST")] public ActionResult EditProduct(int id, [Bind(Include="UnitPrice, ProductName")]Product product) { NORTHWNDEntities entities = new NORTHWNDEntities(); if (ModelState.IsValid) { var dbProduct = entities.ProductSet.First(p => p.ProductID == id); dbProduct.ProductName = product.ProductName; dbProduct.UnitPrice = product.UnitPrice; entities.SaveChanges(); } /* Neither of these work */ product.ProductName = "This has no effect"; ViewData["ProductName"] = "This has no effect either"; return View(product); } Does anyone know what the correct method is for accomplishing this?

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  • Javascript 'class' and singleton problems

    - by Kucebe
    I have a singleton object that use another object (not singleton), to require some info to server: var singleton = (function(){ /*_private properties*/ var myRequestManager = new RequestManager(params, //callbacks function(){ previewRender(response); }, function(){ previewError(); } ); /*_public methods*/ return{ /*make a request*/ previewRequest: function(request){ myRequestManager.require(request); //err:myRequestManager.require is not a func }, previewRender: function(response){ //do something }, previewError: function(){ //manage error } }; }()); This is the 'class' that make the request to the server function RequestManager(params, success, error){ //create an ajax manager this.param = params; this._success = success; //callbacks this._error = error; } RequestManager.prototype = { require: function(text){ //make an ajax request }, otherFunc: function(){ //do other things } } The problem is that i can't call myRequestManager.require from inside singleton object. Firebug consolle says: "myRequestManager.require is not a function", but i don't understand where the problem is. Is there a better solution for implement this situation?

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  • C++ include header conventions

    - by user231536
    Suppose I have a file X.h which defines a class X, whose methods are implemented in X.cc. The file X.h includes a file Y.h because it needs Y to define class X. In X.cc, we can refer to Y because X.h has already included Y.h. Should I still include Y.h in X.cc ? I understand that I don't need to and I can depend on header guards to prevent multiple inclusions. But on the one hand, including Y.h makes X.cc a little more independent of X.h (can't be completely independent of course). What is the accepted practice? Another example: including <iostream> in both .h and .cc files. I see some people do this and some don't.

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  • inspect the parameters to "use", and pass on the rest?

    - by JoelFan
    I have a Perl module and I'd like to be able to pick out the parameters that my my module's user passed in the "use" call. Whichever ones I don't recognize I'd like to pass on. I tried to do this by overriding the "import" method but I'm not having much luck. EDIT: To clarify, as it is, I can use my module like this: use MyModule qw/foo bar/; which will import the foo and bar methods of MyModule. But I want to be able to say: use MyModule qw/foo doSpecialStuff bar/; and look for doSpecialStuff to check if I need to do some special stuff at the beginning of the program, then pass qw/foo bar/ to the Exporter's import

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  • asynchronous calls in asp.net

    - by lockedscope
    in this sample, two threads created; a worker thread created by BeginInvoke and an I/O completion thread created by SendAsync method. but another author in his UnsafeQueueNativeOverlapped example, don't recommend this. i want to use SendAsync or ...Async in an asp.net page and i want to use PageAsyncTask. however, its BeginEventHandler requires AsyncResult to be returned which SendAsync does not return. afaik, event based async pattern is the most recommended way so how could we call SendAsync or any ...Async methods without creating two threads and hurting the performance?

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