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  • Java MouseEvents not working

    - by billynomates
    This may be a stupid question, but I have to ask! I have the following code snippets that are supposed to run their corresponding methods when the user interacts with objects. For some reason, "foo" is never printed, but "bar" is. myJSpinner1.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseEntered(java.awt.event.MouseEvent evt() { System.out.println("foo"); //"foo" is not printed } }); myJSpinner2.addChangeListener(new java.awt.event.ChangeListener() { public void stateChanged(java.awt.event.ChangeEvent evt() { System.out.println("bar"); //"bar" is printed } }); I get no exceptions or stack trace. What am I missing in the MouseListener one? Thanks in advance.

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  • Efficiently making web pages from multiple servers

    - by james.bcn
    I want to create a service that allows diverse web site owners to integrate material from my web servers into content served from their own servers. Ideally the resulting web page would only be delivered from the web site owners server, and the included content would be viewed as being part of the site by Google - which I think would rule out iframes or client-side Javascript to get the content from my server (although I may be wrong about that?). Also the data wouldn't actually be updated that often, say once a day, so it would be inefficient to get the data from my web servers with every request. Finally, the method needs to be as simple as possible so that it is easy for web site owners to integrate into their own sites. Are there any good methods for doing this sort of thing? If not then I guess the simple way is with iframes or Javascript.

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  • grails metaprogramming

    - by Don
    Hi, My understanding is that there are two obvious places in a Grails app where one can do meta-programming: The init closure of Bootstrap.groovy The doWithDynamicMethods closure of a plugin The meta-programming I'm referring to here should be visible throughout the metaprogramming, typical examples include adding (or replacing) methods of 3rd party classes. String.metaClass.myCustomMethod = { /* implementation omitted */ } The disadvantage of (1), is that the metaprogramming won't be applied when the application is dynamically reloaded. The disadvantage of (2) is that I need to create and maintain an entire plugin just for the sake of a little metaprogramming. Is there a better place to do this kind of metaprogramming? Thanks, Don

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  • Memory problem with basic UITableView when scrolling

    - by Sheehan Alam
    I have a very simple UITableView that has 3 sections, and 3 rows per section. #pragma mark - #pragma mark UITableView delegate methods - (NSInteger)tableView:(UITableView *)tblView numberOfRowsInSection:(NSInteger)section { return 3; } - (UITableViewCell *)tableView:(UITableView *)tblView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @"Cell"; UITableViewCell *cell = [tblView dequeueReusableCellWithIdentifier:CellIdentifier]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease]; } // Configure the cell... return cell; } - (NSInteger)numberOfSectionsInTableView:(UITableView *)tblView { if (tblView == self.tableView) { return 3; } else { return 1; } } Everything shows up fine, but as soon as I scroll my application crashes and my debugger tells me: * -[ProfileViewController tableView:cellForRowAtIndexPath:]: message sent to deallocated instance 0x5ae61b0 I'm not exactly sure what I am doing wrong.

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  • Naming a typedef for a boost::shared_ptr<const Foo>

    - by Blair Zajac
    Silly question, but say you have class Foo: class Foo { public: typedef boost::shared_ptr<Foo> RcPtr; void non_const_method() {} void const_method() const {} }; Having a const Foo::RcPtr doesn't prevent non-const methods from being invoked on the class, the following will compile: #include <boost/shared_ptr.hpp> int main() { const Foo::RcPtr const_foo_ptr(new Foo); const_foo_ptr->non_const_method(); const_foo_ptr->const_method(); return 0; } But naming a typedef ConstRcPtr implies, to me, that the typedef would be typedef const boost::shared_ptr<Foo> ConstRcPtr; which is not what I'm interested in. An odder name, but maybe more accurate, is RcPtrConst: typedef boost::shared_ptr<const Foo> RcPtrConst; However, Googling for RcPtrConst gets zero hits, so people don't use this as a typedef name :) Does anyone have any other suggestions?

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  • Authenticate sites with different domain names using the Facebook API

    - by Onema
    We have a CMS that supports multiple sites, one of our features allows our users (The site admin) to connect to the site facebook account to allow status updates, create events and upload pictures to FB from with in the CMS. The authentication needs to occur once since each site may have multiple site admins that do not have access to the site FB user name and password. We use iframe and authenticate using $facebook-require_login() which redirects the user to the FB login and authentication pages. All this works just fine but when the user hits "Allow" the authentication will break as it will only redirect to whatever is in the "Post-Authorize Redirect URL" field making the app obsolete for any other domain except the one in the "Post-Authorize Redirect URL" I know other API's authentication methods like in Vimeo and YouTube will allow you to specify a NEXT parameter which is the equivalent of the "Post-Authorize Redirect URL" and it can be set at run time. How can I make this work for multiple domain names? Any hints on this issue will be of great help

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  • ASP.net MVC 2.0 using the same form for adding and editing.

    - by Chevex
    I would like to use the same view for editing a blog post and adding a blog post. However, I'm having an issue with the ID. When adding a blog post, I have no need for an ID value to be posted. When model binding binds the form values to the BlogPost object in the controller, it will auto-generate the ID in entity framework entity. When I am editing a blog post I DO need a hidden form field to store the ID in so that it accompanies the next form post. Here is the view I have right now. <% using (Html.BeginForm("CommitEditBlogPost", "Admin")) { %> <% if (Model != null) { %> <%: Html.HiddenFor(x => x.Id)%> <% } %> Title:<br /> <%: Html.TextBoxFor(x => x.Title, new { Style = "Width: 90%;" })%> <br /> <br /> Summary:<br /> <%: Html.TextAreaFor(x => x.Summary, new { Style = "Width: 90%; Height: 50px;" }) %> <br /> <br /> Body:<br /> <%: Html.TextAreaFor(x => x.Body, new { Style = "Height: 250px; Width: 90%;" })%> <br /> <br /> <input type="submit" value="Submit" /> <% } %> Right now checking if the model is coming in NULL is a great way to know if I'm editing a blog post or adding one, because when I'm adding one it will be null as it hasn't been created yet. The problem comes in when there is an error and the entity is invalid. When the controller renders the form after an invalid model the Model != null evaluates to false, even though we are editing a post and there is clearly a model. If I render the hidden input field for ID when adding a post, I get an error stating that the ID can't be null. Any help is appreciated. EDIT: I went with OJ's answer for this question, however I discovered something that made me feel silly and I wanted to share it just in case anyone was having a similar issue. The page the adds/edits blogs does not even need a hidden field for id, ever. The reason is because when I go to add a blog I do a GET to this relative URL BlogProject/Admin/AddBlogPost This URL does not contain an ID and the action method just renders the page. The page does a POST to the same URL when adding the blog post. The incoming BlogPost entity has a null Id and is generated by EF during save changes. The same thing happens when I edit blog posts. The URL is BlogProject/Admin/EditBlogPost/{Id} This URL contains the id of the blog post and since the page is posting back to the exact same URL the id goes with the POST to the action method that executes the edit. The only problem I encountered with this is that the action methods cannot have identical signatures. [HttpGet] public ViewResult EditBlogPost(int Id) { } [HttpPost] public ViewResult EditBlogPost(int Id) { } The compiler will yell at you if you try to use these two methods above. It is far too convenient that the Id will be posted back when doing a Html.BeginForm() with no arguments for action or controller. So rather than change the name of the POST method I just modified the arguments to include a FormCollection. Like this: [HttpPost] public ViewResult EditBlogPost(int Id, FormCollection formCollection) { // You can then use formCollection as the IValueProvider for UpdateModel() // and TryUpdateModel() if you wish. I mean, you might as well use the // argument since you're taking it. } The formCollection variable is filled via model binding with the same content that Request.Form would be by default. You don't have to use this collection for UpdateModel() or TryUpdateModel() but I did just so I didn't feel like that collection was pointless since it really was just to make the method signature different from its GET counterpart. Thanks for the help guys!

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  • Dictionary keys don't contain a key that's already contained in keys

    - by ran
    Why is the following 'exist' boolean variable getting a value of false??? foreach (Cell existCell in this.decoratorByCell.Keys) { //this call yield the same hashcode for both cells. still exist==false bool exist = this.decoratorByCell.ContainsKey(existCell); } I've overridden GetHashCode() & Equals() Methods as follows: public override int GetHashCode() { string nodePath = GetNodePath(); return nodePath.GetHashCode() + m_ownerColumn.GetHashCode(); } public bool Equals(Cell other) { bool nodesEqual = (other.OwnerNode == null && this.OwnerNode == null) || (other.GetNodePath() == this.GetNodePath()); bool columnsEqual = (other.OwnerColumn == null && this.OwnerColumn == null) || (other.OwnerColumn == this.OwnerColumn); bool treesEqual = (this.m_ownerTree == other.m_ownerTree); return (nodesEqual && columnsEqual && treesEqual); }

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  • FMDB transaction

    - by user142764
    Hi ! I use FMDB to wrap SQLite in my app. I haven't found any docs about the use of methods begin, beginUpdates, commit, finalize, etc. I face some problems in my apps which i think are caused by the way i use transactions. Here is what i tried : [FMDB beginUpdates] - My insert statement - [FMDB commit] [FMDB finalize] it crashes with this log : Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[FMDatabase<0xd705a0 finalize]: called when collecting not enabled' Could you please give me an example of how you are using transactions, or point me to a doc ? Thanks in advance, Vincent.

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  • Cloning java ArrayList and preventing it from modifications

    - by user222164
    I have a data structure like a database Rowset, which has got Rows and Rows have Columns. I need to initialize a Columns with null values, current code is to loop thru each column for a row and initialize values to NULL. Which is very inefficient if you have 100s or rows and 10s of column. So instead I am keeping a initialized ArrayList of columns are RowSet level, and then doing a clone of this Arraylist for individual rows, as I believe clone() is faster than looping thru each element. row.columnsValues = rowsset.NullArrayList.clone() Problem with this is NullArrayList can be accidentally modified after being cloned, thus sacrificing the integrity of ArrayList at RowSet level, to prevent I am doing 3 things 1) Delcaring ArrayList as final 2) Any elements I insert are final or null 3) Methods thurough this arrayList are passed to other arrays are declared a final. Sounds like a plan, do you see any holes ?

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  • Database Replication OOD Pattern

    - by MrOnigiri
    Greetings fellow overflowers, After reading on MSDN about correct strategies on how to perform database replication, and understanding their suggestion on Master-Subordinate Incremental Replication. It left me wondering, what OOD design pattern should I use on this... The main elements of this strategy are the Acquirer, the Manipulator and the Writer. The first fetches data from the database and passes on to the second which might perform simple transformations to the data, before handling it to the final element, the writer, that writes the desired data on the destination Database. I thought about using the Chain of Responsibility pattern, but the Acquirer, Manipulator and Writer don't share a common role among theme, so It makes no sense. Should these elements be written as separate classes, or methods inside my service? Of course I'll be creating a DB Helper class as well, but that doesn't constitutes a problem. Wondering what your opinions on this are! Thanks for your replies

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  • Rails: Skinny Controller vs. Fat Model, or should I make my Controller Anorexic?

    - by Nick Gorbikoff
    I know similar questions have been answered before - such as: Where should logic go, where to do certain tasks, etc. But I have a more specific question - How far should I take this axiom: "keep your controller skinny, make your model fat!" Here is an example: For instance let's say I have multiple source of verification data. A good example would be a VIN number - I can verify it against, manufacturers data source, DMV's data source, also my local databases - to see what I have on record. So I have a model called Vin and vins_controller. Inside the model I have 5 methods: check_against_local_db, check_against_dmv, check_against_car_maker_1, check_against_car_maker_2, etc. In my controller keeping with the REST, in action show - I have a simple case statement which looks at the params[:source], and based on source specified - will call specific check method. Now here is the question: Should I leave the logic that governs which data source to call in controller or should I move it to model and then in controller just do something like check_vin(source, vin)? Should I make my controller anorexic?

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  • Dynamically load .asmx web-service

    - by Tierney
    I have an .aspx page that can perform a number of functions. The type of function is determined at run-time depending on which button the user clicks. This makes makes a web-service call to an .asmx method. The web-service call returns html and javascript which then become part of the original page. This new content has javascript events attached to button clicks, data validation etc. In turn these events then call their own web-service methods in another .asmx file. The main page does not know about these other .asmx files when the page loads. So, is there any way of dynamically loading these .asmx files on demand?

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  • Controller getting NULL value?

    - by RSolberg
    I'm trying to make a call to a controller via jQuery $.post, but the parameter for my controller method keeps getting a NULL value despite it appearing to be setup similar to other controller methods. CONTROLLER [AcceptVerbs(HttpVerbs.Post)] public ActionResult SearchWeatherLocations(string searchFor) { //Do Some Magic } GLOBAL.ASAX routes.MapRoute("SearchWeatherLocations", "Home/SearchWeatherLocations/{searchFor}", new { controller = "Home", action = "SearchWeatherLocations" }); jQuery Call From View <script type="text/javascript" language="javascript"> $(document).ready(function () { GetWeatherLocations("seat"); }); function GetWeatherLocations(sSearchFor) { var divToBeWorkedOn = '#locations'; var webMethod = '<%= Url.Action("SearchWeatherLocations", "Home") %>/'; var url = webMethod + sSearchFor; $.post(url, function (data) { $('#locations').children().remove(); for (var count in data) { $('#locations').append("<li>" + data[count].LocationName + "&nbsp;(" + data[count].LocationCode + ")</li>"); } }); } </script>

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  • Use of COM object in IIS 7

    - by Wouter d.A.
    Hi all, I am currently moving an ASP.NET web-project from an IIS 6 to a IIS 7 hosting environment. Everything seems to be running OK, except my calls to a COM object. I can perfectly instantiate an object of the COM type, but when I call one of its methods, the IIS crashes. The event log reports an error code "0xc0000374", which indicates a heap corruption. When I run the application inside the visual studio development server, everything goes well and the COM object code gets executed without any errors. This is also the case when the application is hosted on an IIS 6 machine. I have looked through all settings of the IIS 7 and have not found anything configurable for COM objects, like security or ... I have been struggling with this for a while and I'm out of ideas. Does anyone have any experience deploying COM objects on IIS 7? Your help would be very appreciated!

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  • Temp file that exists only in RAM?

    - by Auraomega
    I'm trying to write an encrpytion using the OTP method. In keeping with the security theories I need the plain text documents to be stored only in memory and never ever written to a physical drive. The tmpnam command appears to be what I need, but from what I can see it saves the file on the disk and not the RAM. Using C++ is there any (platform independent) method that allows a file to exist only in RAM? I would like to avoid using a RAM disk method if possible. Thanks Edit: Thanks, its more just a learning thing for me, I'm new to encryption and just working through different methods, I don't actually plan on using many of them (esspecially OTP due to doubling the original file size because of the "pad"). If I'm totally honest, I'm a Linux user so ditching Windows wouldn't be too bad, I'm looking into using RAM disks for now as FUSE seems a bit overkill for a "learning" thing.

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  • Logging with log4j on tomcat jruby-rack for a Rails 3 application

    - by John
    I just spent the better part of 3 hours trying to get my Rails application logging with Log4j. I've finally got it working, but I'm not sure if what I did is correct. I tried various methods to no avail until my various last attempt. So I'm really looking for some validation here, perhaps some pointers and tips as well -- anything would be appreciated to be honest. I've summarized all my feeble methods into three attempts below. I'm hoping for some enlightenment on where I went wrong with each attempt -- even if it means I get ripped up. Thanks for the help in advance! System Specs Rails 3.0 Windows Server 2008 Log4j 1.2 Tomact 6.0.29 Java 6 Attempt 1 - Configured Tomcat to Use Log4J I basically followed the guide on the Apache Tomcat website here. The steps are: Create a log4j.properties file in $CATALINA_HOME/lib Download and copy the log4j-x.y.z.jar into $CATALINA_HOME/lib Replace $CATALINA_HOME/bin/tomcat-juli.jar with the tomcat-juli.jar from the Apache Tomcat Extras folder Copy tomcat-juli-adapters.jar from the Apache Tomcat Extras folder into $CATALINA_HOME/lib Delete $CATALINA_BASE/conf/logging.properties Start Tomcat (as a service) Expected Results According to the Guide I should have seen a tomcat.log file in my $CATALINA_BASE/logs folder. Actual Results No tomcat.log Saw three of the standard logs instead jakarta_service_20101231.log stderr_20101231.log stdout_20101231.log Question Shouldn't I have at least seen a tomcat.log file? Attempt 2 - Use default Tomcat logging (commons-logging) Reverted all the changes from the previous setup Modified $CATALINA_BASE/conf/logging.properties by doing the following: Adding a setting for my application in the handlers line: 5rails3.org.apache.juli.FileHandler Adding Handler specific properties 5rails3.org.apache.juli.FileHandler.level = FINE 5rails3.org.apache.juli.FileHandler.directory = ${catalina.base}/logs 5rails3.org.apache.juli.FileHandler.prefix = rails3. Adding Facility specific properties org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/rails3].level = INFO org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/rails3].handlers = 4host-manager.org.apache.juli.FileHandler Modified my web.xml by adding the following context parameter as per the Logging section of the jruby-rack readme (I also modified my warbler.rb accordingly, but I did opted to change the web.xml directly to test things faster). <context-param> <param-name>jruby.rack.logging</param-name> <param-value>commons_logging</param-value> </context-param> Restarted Tomcat Results A log file was created (rails3.log), however there was no log information in the file. Attempt 2A - Use Log4j with existing set up I decided to go Log4j another whirl with this new web.xml setting. Copied the log4j.jar into my WEB-INF/lib folder Created a log4j.properties file and put it into WEB-INF/classes log4j.rootLogger=INFO, R log4j.logger.javax.servlet=DEBUG log4j.appender.R=org.apache.log4j.RollingFileAppender log4j.appender.R.File=${catalina.base}/logs/rails3.log log4j.appender.R.MaxFileSize=5036KB log4j.appender.R.MaxBackupIndex=4 log4j.appender.R.layout=org.apache.log4j.PatternLayout log4j.appender.R.layout.ConversionPattern=%d{dd MMM yyyy HH:mm:ss} [%t] %-5p %c %x - %m%n Restarted Tomcat Results Same as Attempt 2 NOTE: I used log4j.logger.javax.servlet=DEBUG because I read in the jruby-rack README that all logging output is automatically redirected to the javax.servlet.ServletContext#log method. So I though this would capture it. I was obviously wrong. Question Why didn't this work? Isn't Log4J using the commons_logging API? Attempt 3 - Tried out slf4j (WORKED) A bit uncertain as to why Attempt 2A didn't work, I thought to myself, maybe I can't use commons_logging for the jruby.rack.logging parameter because it's probably not using commons_logging API... (but I was still not sure). I saw slf4j as an option. I have never heard of it and by stroke of luck, I decided to look up what it is. After reading briefly about what it does, I thought it was good of a shot as any and decided to try it out following the instructions here. Continuing from the setup of Attempt 2A: Copied slf4j-api-1.6.1.jar and slf4j-simple-1.6.1.jar into my WEB-INF/lib folder I also copied slf4j-log4j12-1.6.1.jar into my WEB-INF/lib folder Restarted Tomcat And VIOLA! I now have logging information going into my rails3.log file. So the big question is: WTF? Even though logging seems to be working now, I'm really not sure if I did this right. So like I said earlier, I'm really looking for some validation more or less. I'd also appreciate any pointers/tips/advice if you have any. Thanks!

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  • Rails: Convert HTML to PDF?

    - by rip747
    What is the best and easiest way of taking HTML and converting it into a PDF, similar to use CFDOCUMENT on ColdFusion? UPDATE: I really appreciate all the comments and suggestions that people have given so far, however I feel that people leaving their answers are missing the point. 1) the solution has to be free or open sourced. one person suggested using pricexml and the other pd4ml. both of these solutions costs money (pricexml costing an arm and a leg) which i'm not about the fork over. 2) they must be able to take in html (either from a file, url or a string variable) and then produce the pdf. libraries like prawn, rprf, rtex are produced using their own methods and not taking in html. please don't think i'm ungrateful for the suggestions, it's just that pdf generation seems like a really problem for people like me who use ColdFusion but want to convert to Rails.

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  • Setting a "dependency property" in code

    - by Matt B
    I'm on a roll today... I have the following code delaring a dependency property inside a class called ActionScreen: #region Dependency Properties & Methods public string DescriptionHeader { get { return (string)GetValue(DescriptionHeaderProperty); } set { SetValue(DescriptionHeaderProperty, value); } } // Using a DependencyProperty as the backing store for DescriptionHeader. This enables animation, styling, binding, etc... public static readonly DependencyProperty DescriptionHeaderProperty = DependencyProperty.Register("DescriptionHeader", typeof(string), typeof(ActionScreen), new UIPropertyMetadata("xxx")); #endregion I bind to this property in my Xaml as so: <GridViewColumn DisplayMemberBinding="{Binding Description}" Header="{Binding DescriptionHeader}" Width="350" /> Now I want to be able to set the parameter from my code behind when I recieve an event - but it's not working: public string DescColText { set { this.Dispatcher.Invoke(DispatcherPriority.Normal, new Action(delegate() { DescriptionHeader = value; })); } }

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  • Mod rewrite with 3 parameters ?

    - by Axel
    Hello, I did tons of methods to figure out how to make this mod rewrite but i was completly unsuccessful. I want a .htaccess code that rewrite in the following method: http://www.mydomain.com/apple/upcoming/2 --- http://www.mydomain.com/handler.php?topic=apple&orderby=upcoming&page=2 This is easy to do, but the problem is that all parameters are not required so the link has different levels of parameters each time like this: http://www.mydomain.com/apple/popular/2 -- topic=apple&orderby=popular&page=2 http://www.mydomain.com/apple/2 -- topic=apple&orderby=&page=2 http://www.mydomain.com/all/popular/2 -- topic=all&orderby=popular&page=2 http://www.mydomain.com/apple/upcoming/ -- topic=apple&orderby=upcoming&page= So briefly, the url has 3 optional parameters in one static order: (topic) (orderby) (page) Note: the ORDERBY parameter can be "popular" or "upcoming" or nothing. Thanks

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  • How to get window opened/closed/minimized messages from a native app?

    - by Josh Santangelo
    It's tough to write a good title for this one. I'm working on a WPF application which needs to know about the existence of all other open windows on the system. I'm able to do this by calling the native EnumWindows method just fine, and I can call other native methods to filter out just the windows I'm interested in. This works well. The problem I'm having is that I want to know when a window is opened or closed (and, ideally, minimized). I can do this by polling with EnumWindows, but I'm finding that to be pretty slow, even if I push it off to another thread. Is there a better way to get notifications of window opened/closed/minimized? Keep in mind that my knowledge of non-managed code is pretty limited.

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  • Flatten a PHP array

    - by deadkarma
    Say I have a form with these fields, and cannot rename them: <input type="text" name="foo[bar]" /> <input type="text" name="foo[baz]" /> <input type="text" name="foo[bat][faz]" /> When submitted, PHP turns this into an array: Array ( [foo] => Array ( [bar] => foo bar [baz] => foo baz [bat] => Array ( [faz] => foo bat faz ) ) ) What methods are there to convert or flatten this array into a data structure such as: Array ( [foo[bar]] => foo bar [foo[baz]] => foo baz [foo[bat][faz]] => foo bat faz )

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  • Is NServiceBus suitable for general as well specific client notifications

    - by Pratik
    I am looking at various options for a WCF based publish subscribe framework. Say I have one WCF web service that will be the publisher and 1000 clients registered as subscriber. For some published messages all clients will be interested but at the same time I wish the ability to notify a single client with a specific message. On receiving notification the client will call other web service methods on the web service. Is NServiceBus suitable for this kind of scenario ? If I use MSMQ for transport does it mean that every PC where the client is installed requires a queue to be created ?

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  • Arraylist is null; I cannot access books in the arraylist

    - by user3701380
    I am a beginner-intermediate java programmer and I am getting a null pointer exception from my arraylist. I am writing a bookstore program for APCS and when i add the book, it is supposed to add to the arraylist in the inventory class. But when i call a method to search for a book (e.g. by title), it shows that there isn't anything in the arraylist. //Here is my inventory class -- it has all methods for adding the book or searching for one The searching methods are in getBookByTitle, getBookByAuthor, and getBookByISBN and the method for adding a book is addBook package webbazonab; //Inventory Class //Bharath Senthil //Ansh Sikka import java.util.ArrayList; public class Inventory{ private ArrayList<Book> allBooks = new ArrayList<Book>(); private String bookTitles; private String bookAuthors; private String bookPrices; private String bookCopies; private String ISBNs; public Inventory() { } //@param double price, int copies, String bookTitle, String Author, String isbnNumber public void addBooks(Book addedBook){ allBooks.add(addedBook); } public boolean isAvailable(){ for(Book myBook : allBooks){ if(myBook.copiesLeft() == 0) return false; } return true; } public String populateTitle(){ for (Book titleBooks : allBooks){ bookTitles = titleBooks.getTitle() + "\n"; return bookTitles; } return bookTitles; } public String populateAuthor(){ for(Book authorBooks : allBooks){ bookAuthors = authorBooks.getAuthor() + "\n"; return bookAuthors; } return bookAuthors; } public String populatePrice(){ for (Book pricedBooks : allBooks){ bookPrices = String.valueOf(pricedBooks.getPrice()) + "\n"; } return "$" + bookPrices; } /** * * @return */ public String populateCopies(){ for (Book amtBooks : allBooks){ bookCopies = String.valueOf(amtBooks.copiesLeft()) + "\n"; return bookCopies; } return bookCopies; } public String populateISBN(){ for (Book isbnNums : allBooks){ ISBNs = isbnNums.getIsbn() + "\n"; return ISBNs; } return ISBNs; } @SuppressWarnings("empty-statement") public Book getBookByTitle(String titleSearch) { for(Book titleBook : allBooks) { if (titleBook.getTitle().equals(titleSearch)) { return titleBook; } } return null; } public Book getBookByISBN(String isbnSearch){ for(Book isbnBookSearches : allBooks){ if(isbnBookSearches.getIsbn().equals(isbnSearch)){ return isbnBookSearches; } } return null; } public Book getBookByAuthor(String authorSearch){ for(Book authorBookSearches : allBooks){ if(authorBookSearches.getAuthor().equals(authorSearch)){ return authorBookSearches; } } return null; } public void sort(){ for(int i = 0; i < allBooks.size(); i++) { for(int k = 0; k < allBooks.size(); k++) { if(((Book) allBooks.get(i)).getIsbn().compareTo(((Book) allBooks.get(k)).getIsbn()) < 1) { Book temp = (Book) allBooks.get(k); allBooks.set(k, allBooks.get(i)); allBooks.set(i, temp); } else if(((Book) allBooks.get(i)).getIsbn().compareTo(((Book) allBooks.get(k)).getIsbn()) > 1) { Book temp = (Book) allBooks.get(i); allBooks.set(i, allBooks.get(k)); allBooks.set(k, temp); } } } } public ArrayList<Book> getBooks(){ return allBooks; } } //The exception occurs when i call the method here (in another class): Inventory lib = new Inventory(); jTextField12.setText(lib.getBookByAuthor(authorSearch).getTitle()); Here is my book class if you need it package webbazonab; //Webbazon AB //Project By: Ansh Sikka and Bharath Senthil public class Book { private double myPrice; private String myTitle; private String bookAuthor; private String isbn; private int myCopies; public Book(double price, int copies, String bookTitle, String Author, String isbnNumber) { myPrice = price; myCopies = copies; myTitle = bookTitle; bookAuthor = Author; isbn = isbnNumber; } public double getPrice() { return myPrice; } public String getIsbn() { return isbn; } public String getTitle() { return myTitle; } public String getAuthor() { return bookAuthor; } public int copiesLeft(){ return myCopies; } public String notFound(){ return "The book you searched for could not be found!"; } public String toString() { return "Title: " + getTitle() + "\nAuthor: " + getAuthor() + "\nNumber of Available Books: " + copiesLeft() + "\nPrice: $" + getPrice(); } } Thanks!

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  • Why are alloc and init called separately in Objective-C?

    - by André Hoffmann
    Note: I'm relatively new to Objective-C and am coming from Java and PHP. Could someone explain to me why I always have to first allocate and then initialize an instance? Couldn't this be done in the init methods like this: + (MyClass*)init { MyClass *instance = [MyClass alloc]; [instance setFoo:@"bla"]; return instance; } + (MyClass*)initWithString:(NSString*)text { MyClass *instance = [MyClass init]; [instance setFoo:text]; return instance; } ... Is this just a relict from the old C days or is there something that I'm not seeing? I know this isn't a problem as I could as well always call alloc and init, but since it's a bit tedious I'd like to at least know why I'm doing it. I'm liking the expressiveness of the language so far, but this is something that I want to fully understand in order to think the Objective-C way. Thank you!

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