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  • Linking Listbox child categories

    - by Gerardo Abdo
    Hello I have few monhts working with aspx, and now I'm developing a shopping cart website. For the employee to upload the products on the DB, every product needs to be linked to a category and sub category, and sub-sub category, and so on. Sometimes the sub-sub categories are up to 5. For example Electronics-TV-LCD-Samsung-40 inches. First, What I would like to identify is if the SQL table has the apporpiate structure. I have 3 columns Id, Description, Parent_Id. Categories with Parent Id=0 is used for the top ones. Is this the best way to do it? Then I want to use the ListBox control to select main Categories, and once it is selected, filled a second listbox with its childs and so on. Do I need to query SQL DB everytime the change event happens? I heard about linq but have not used yet, What would be your suggestion to do this. If you have seen a sample to understand it better will be appreciated. Thank you

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  • Why am I having this InstantiationException in Java when accessing final local variables?

    - by Oscar Reyes
    I was playing with some code to make a "closure like" construct ( not working btw ) Everything looked fine but when I tried to access a final local variable in the code, the exception InstantiationException is thrown. If I remove the access to the local variable either by removing it altogether or by making it class attribute instead, no exception happens. The doc says: InstantiationException Thrown when an application tries to create an instance of a class using the newInstance method in class Class, but the specified class object cannot be instantiated. The instantiation can fail for a variety of reasons including but not limited to: - the class object represents an abstract class, an interface, an array class, a primitive type, or void - the class has no nullary constructor What other reason could have caused this problem? Here's the code. comment/uncomment the class attribute / local variable to see the effect (lines:5 and 10 ). import javax.swing.*; import java.awt.event.*; import java.awt.*; class InstantiationExceptionDemo { //static JTextField field = new JTextField();// works if uncommented public static void main( String [] args ) { JFrame frame = new JFrame(); JButton button = new JButton("Click"); final JTextField field = new JTextField();// fails if uncommented button.addActionListener( new _(){{ System.out.println("click " + field.getText()); }}); frame.add( field ); frame.add( button, BorderLayout.SOUTH ); frame.pack();frame.setVisible( true ); } } class _ implements ActionListener { public void actionPerformed( ActionEvent e ){ try { this.getClass().newInstance(); } catch( InstantiationException ie ){ throw new RuntimeException( ie ); } catch( IllegalAccessException ie ){ throw new RuntimeException( ie ); } } } Is this a bug in Java? edit Oh, I forgot, the stacktrace ( when thrown ) is: Caused by: java.lang.InstantiationException: InstantiationExceptionDemo$1 at java.lang.Class.newInstance0(Class.java:340) at java.lang.Class.newInstance(Class.java:308) at _.actionPerformed(InstantiationExceptionDemo.java:25)

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  • Different Scala Actor Implementations Overview

    - by Stefan K.
    I'm trying to find the 'right' actor implementation for my thesis. I realized there is a bunch of them and it's a bit confusing to pick one. Personally I'm especially interested in remote actors, but I guess a complete overview would be helpful to many others. This is a pretty general question, so feel free to answer just for the implementation you know about. I know about the following Scala Actor implementations (SAI). Please add the missing ones. Scala 2.7 (difference to) Scala 2.8 Akka (http://www.akkasource.org/) Lift (http://liftweb.net/) Scalaz (http://code.google.com/p/scalaz/) What are the target use-cases for these SAIs (lightweight vs. "heavy" enterprise framework)? do they support remote actors? What shortcomings do remote actors have in the SAIs? How is their performace? How active is there community? How easy are they to get started? How good is the documentation? How easy are they to extend? How stable are they? Which projects are using them? What are their shortcomings? What are their design principles? Are they thread based or event based (receive/ react) or both? Nested receiveS hotswapping the Actor’s message loop

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  • Dynamcally resizing an open Accordion

    - by alavers
    I have an Accordion and the height of its content can be dynamically resized. I would like to see the Accordion dynamically respond to the child item's height, but I'm having trouble doing this. <lt:Accordion Name="MyAccordion" SelectionMode="ZeroOrOne" HorizontalAlignment="Stretch"> <lt:AccordionItem Name="MyAccordionItem" Header="MyAccordion" IsSelected="True" HorizontalContentAlignment="Stretch" VerticalAlignment="Stretch"> <StackPanel> <Button Content="Grow" Click="Grow"/> <Button Content="Shrink" Click="Shrink"/> <TextBox Name="GrowTextBox" Text="GrowTextBox" Height="400" Background="Green" SizeChanged="GrowTextBox_SizeChanged"/> </StackPanel> </lt:AccordionItem> </lt:Accordion> private void Grow(object sender, System.Windows.RoutedEventArgs e) { GrowTextBox.Height += 100; } private void Shrink(object sender, System.Windows.RoutedEventArgs e) { GrowTextBox.Height -= 100; } private void GrowTextBox_SizeChanged(object sender, System.Windows.SizeChangedEventArgs e) { MyAccordion.UpdateLayout(); MyAccordionItem.UpdateLayout(); } Mind you, if I collapse and then re-open the accordion, it takes shape just the way I want, but I'd like this resizing to occur immediately when the child resizes. I feebly attempted to fix this by adding a SizeChanged event handler that calls UpdateLayout() on the Accordion and AccordionItem, but this doesn't have any visual effect. I can't figure out where proper resizing takes place inside the Accordion control. Does anyone have an idea?

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  • unable to get data from iphone application

    - by user317192
    Hi, I have made a php web services that takes the username and password from iPhone application and saves the data in the users table. I call that web service from my button touchup event like this: NSLog(userName.text); NSLog(password.text); NSString * dataTOB=[userName.text stringByAppendingString:password.text]; NSLog(dataTOB); NSData * postData=[dataTOB dataUsingEncoding:NSUTF8StringEncoding allowLossyConversion:YES]; NSString *postLength = [NSString stringWithFormat:@"%d", [postData length]]; NSLog(postLength); NSMutableURLRequest *request = [[[NSMutableURLRequest alloc] init] autorelease]; NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:@"http://localhost:8888/write.php"]]; [request setURL:url]; [request setHTTPMethod:@"POST"]; [request setValue:postLength forHTTPHeaderField:@"Content-Length"]; [request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"]; [request setHTTPBody:postData]; NSURLResponse *response; NSError *error; [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error]; if(error==nil) NSLog(@"Error is nil"); else NSLog(@"Error is not nil"); NSLog(@"success!"); I am getting nothing from Iphone side into the web service and I am unable to understand why this is happening. Although i debugged and found that everything is fine at the iphone application level but the call to the web service doesn't works as expected...... Please suggest..... Thanks Ashish

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  • Add delay and focus for a dead simple accordion jquery

    - by kuswantin
    I found the code somewhere in the world, and due to its dead simple nature, I found some things in need to fix, like when hovering the trigger, the content is jumping up down before it settled. I have tried to change the trigger from the title of the accordion block to the whole accordion block to no use. I need help to add a delay and only do the accordion when the cursor is focus in the block. I have corrected my css to make sure the block is covering the hidden part as well when toggled. Here is my latest modified code: var acTrig = ".accordion .title"; $(acTrig).hover(function() { $(".accordion .content").slideUp("normal"); $(this).next(".content").slideDown("normal"); }); $(acTrig).next(".content").hide(); $(acTrig).next(".content").eq(0).css('display', 'block'); This is the HTML: <div class="accordion clearfix"> <div class="title">some Title 1</div> <div class="content"> some content blah </div> </div> <div class="accordion clearfix"> <div class="title">some Title 2</div> <div class="content"> some content blah </div> </div> <div class="accordion clearfix"> <div class="title">some Title 3</div> <div class="content"> some content blah </div> </div> I think I need a way to stop event bubbling somewhere around the code, but can't get it right. Any help would be very much appreciated. Thanks as always.

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  • Why is the ASP.NET Repeater.Items collection empty, when controls are on the screen?

    - by Ryan
    I have an ASP page with the following repeater: <asp:Repeater runat="server" ID="RegionRepeater" DataSourceID="SqlDataSourceRegions" EnableViewState="true"> <ItemTemplate> <tr> <td valign="top"> <b><%#Eval("description")%></b> <asp:HiddenField runat="server" ID="RegionID" Value='<%#Eval("region_id")%>'/> </td> <td> <asp:FileUpload ID="FileUpload" runat="server" Width="368px" /> </td> </tr> </ItemTemplate> </asp:Repeater> (The repeater is inside a Wizard, inside a content pane). The code behind is connected to the protected void Wizard1_NextButtonClick(object sender, WizardNavigationEventArgs e) event. There are two items on the screen (two rows inside the table). However, when the code tries to read those items, the Items collection is empty! foreach(RepeaterItem region in RegionRepeater.Items) { // Never runs - the RegionRepeater.Items.Count = 0 FileUpload fileUpload = (FileUpload) region.FindControl("FileUpload"); String regionID = ((HiddenField)region.FindControl("RegionID")).Value; ... Why is the collection empty, when there are controls drawn on the screen? Thanks a lot for any help; this is starting to drive me nuts. (BTW: I tried adding/removing the EnableViewState="true" tag)

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  • JQuery and IE8 - Form posting on tab change

    - by Tommy
    This issue is only happening in IE8 - Firefox 3.5 seems to handle it fine. I have JQuery UI tabs setup on a page. Within each tab is a form that users can do stuff from. I have defined in the select option of the using: $("#tabs").tabs({select: function(event, ui) {...}}); a submitForm function that submits the form of the tab the user was on previous to changing tabs. This all works in all browsers. The issue comes in that IE does both the POST of the form on the previous tab and the GET for content of the newly requested tab and or really close to the same time (from what I can tell walking through the debugger). As a result, if a tab is dependent on the form input from another tab, the data is stale - does not match the user input from the previous tab. How can I either a) force the POST to complete before rendering the next tab or b) force IE to not make the POST and GET for the next tab at the same time?...or c) some other option?

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  • Fastcgi 500 error on preg_match_all in PHP

    - by Bertvan
    Hi, I'm trying to set up some exotic PHP code (I'm no expert), and I get a FastCGI Error 500 on a PHP line containing 'preg_match_all'. When I comment out the line, the page is returned with a 200 (but not how it was meant to be). The code is parsing php, html and javascript content loaded from the database and is composing them to return the finished page. Now, by placing around some error_log entries I could determine that the line with the preg_match_all is the cause of the 500. However the line is hit multiple times during the loading of the page and on other occasions, the line does not cause an error. Here's how it looks like exactly: preg_match_all ("/(<([\w]+)[^>]*>)((?:.|\n)*)(<\/\\2>)/", $part['data'], $tags, PREG_PATTERN_ORDER|PREG_OFFSET_CAPTURE); The subject string is a piece of text that looks like: <script> ... some javascript functions ... </script> [Edit:] This is code that is up and running correctly elsewhere, so this very well could be a PHP setting or environment difference. I'm using PHP 5.2.13 on IIS6 with FastCGI. [Edit:] Nothing is mentioned in the log files. At least not in the ones I checked: IIS Logs Event Logs PHP Log Any thoughts or direction would be welcome.

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  • Editing list properties using DataGridview

    - by toom
    Ok, I have my custom class: public class FileItem : INotifyPropertyChanged { int id=0; string value=""; public int Id { get { return id; } set { id = value; Changed("Id"); } } public string Value { get { return value; } set { this.value = value; Changed("Value"); } } public event PropertyChangedEventHandler PropertyChanged; void Changed(string name) { if (PropertyChanged != null) PropertyChanged(this, new PropertyChangedEventArgs(name)); } } public BindingList<FileItem> FilesystemEntries = new BindingList<FileItem>(); And I have DatagridView1 with DataSource set to FilesystemEntries: binding.DataSource = FilesystemEntries; Already I can Add and remove rows - these chnages are reflected on collection. However, Value and Id are not saved into bidning list when i change them in DataGridView, id is always 0 and value is "". How can I make this work? Do I need to implement some interface to FileItem to allow editing properties? ReadOnly of DGV is set to false, same to all columns. Editing, Deleting and Changing are enabled.

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  • By Pressing Enter key move to next Textbox in ASP.Net

    - by Malik Usman
    I have two textboxes and one Button control.....In first TextBox when press enter key moves to next textbox(Barcode) and when i press enter in barcode textbox it fires the button click event......till that its ok.... But what happening after fireing the Button click even on enter in Barcode Textbox its going back to focus on first textbox.........But i want this to stay in same Barcode TextBox to scan more barcodes. The code is below. <script type="text/javascript" src="http://ajax.microsoft.com/ajax/jquery/jquery-1.4.2.min.js"> </script> <Head> <script type="text/javascript"> $(function() { $('input:text:first').focus(); var $inp = $('input:text'); $inp.bind('keydown', function(e) { //var key = (e.keyCode ? e.keyCode : e.charCode); var key = e.which; if (key == 13) { e.preventDefault(); var nxtIdx = $inp.index(this) + 1; $(":input:text:eq(" + nxtIdx + ")").focus(); } }); }); </script> </Head>

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  • Message queue proxy in Python + Twisted

    - by gasper_k
    Hi, I want to implement a lightweight Message Queue proxy. It's job is to receive messages from a web application (PHP) and send them to the Message Queue server asynchronously. The reason for this proxy is that the MQ isn't always avaliable and is sometimes lagging, or even down, but I want to make sure the messages are delivered, and the web application returns immediately. So, PHP would send the message to the MQ proxy running on the same host. That proxy would save the messages to SQLite for persistence, in case of crashes. At the same time it would send the messages from SQLite to the MQ in batches when the connection is available, and delete them from SQLite. Now, the way I understand, there are these components in this service: message listener (listens to the messages from PHP and writes them to a Incoming Queue) DB flusher (reads messages from the Incoming Queue and saves them to a database; due to SQLite single-threadedness) MQ connection handler (keeps the connection to the MQ server online by reconnecting) message sender (collects messages from SQlite db and sends them to the MQ server, then removes them from db) I was thinking of using Twisted for #1 (TCPServer), but I'm having problem with integrating it with other points, which aren't event-driven. Intuition tells me that each of these points should be running in a separate thread, because all are IO-bound and independent of each other, but I could easily put them in a single thread. Even though, I couldn't find any good and clear (to me) examples on how to implement this worker thread aside of Twisted's main loop. The example I've started with is the chatserver.py, which uses service.Application and internet.TCPServer objects. If I start my own thread prior to creating TCPServer service, it runs a few times, but the it stops and never runs again. I'm not sure, why this is happening, but it's probably because I don't use threads with Twisted correctly. Any suggestions on how to implement a separate worker thread and keep Twisted? Do you have any alternative architectures in mind?

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  • java annotations - problem with calling a locator class from a Vaadin Project

    - by George
    Hello, I'm not sure how to explain this without writing several pages so I hope the actual code is more expressive. I've made a jar containing multiple annotation declaration similar to the following: @Target(ElementType.PACKAGE) @Retention(RetentionPolicy.RUNTIME) public @interface MarkedPackage { } then I have made a test jar containing several classes in several packages and marked just one package with the above annotation (with package-info.java) like below: @myPackage.MarkedPackage package package.test.jar; this jar had in its build path the jar containing the annotations. then I made a static class that has a method (LoadPlugins) that retrieves a list with all the jars of a directory. Then it searches through the jars for the 'package-info' class and checks if that classes package contains the MarkedPackage annotation. by calling this: if (checkPackageAnnotation(thisClass.getPackage())) where thisClass is the package-info class retrieved via a classloader. and: public static boolean checkPackageAnnotation(AnnotatedElement elem) { System.out.println(elem.getAnnotations().length); if (elem == null || !elem.isAnnotationPresent(MarkedPackage.class)) return false; return true; } the elem.getAnnotatios().length is there for debug purposes. And the problem appears when I call the method from the static class: if I call it from a main function: public class MyMain { public static void main(String[] args){ PluginUtils.LoadPlugins(); } } everything works perfectly it displays '1' from that System.out.println(elem.getAnnotations().length); But if I call it from a button from my Vaadin project: header.addComponent(new Button("CallThat", new Button.ClickListener() { public void buttonClick(ClickEvent event) { PluginUtils.LoadPlugins(); } })); It displays '0' from that System.out.println(elem.getAnnotations().length); Also I should mention that I created the main inside my Vaadin project so it would have the exact same build path and resources. Is there a problem with web applications and that "@Retention(RetentionPolicy.RUNTIME)" ? hope I was clear enough... Hope someone has a solution for me... If you need more information - let me know. Thank you.

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  • How to get Facebook Login Button To Display "Logout"

    - by Will Merydith
    I apologize ahead of time if this is clearly documented somewhere on the FB developer site - but I can't find it (so please link me if appropriate). I've implemented the FB login button on a website using GAE + Python. Here is the HTML: <fb:login-button></fb:login-button> <div id="fb-root"></div> <script src="http://connect.facebook.net/en_US/all.js"></script> <script> FB.init({appId: 'ad16a806fc10bef5d30881322e73be68', status: true, cookie: true, xfbml: true}); FB.Event.subscribe('auth.sessionChange', function(response) { if (response.session) { // A user has logged in, and a new cookie has been saved } else { // The user has logged out, and the cookie has been cleared } }); </script> Currently the behavior is - if I click on the "login" button, I am asked to allow the application access to FB. Which I then choose, "OK". But then the login button is still showing "login" and not "logout". How do I implement that? On the server or client side?

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  • Bing Map on Windows Phone - add click events to pushpins; display more details

    - by Will Gill
    I have a WP Phone app using a Bing Map control. I have an array of objects, and each object has a location. I iterate the array to place the pins on the map (see below). I have a touch event bound to each pin to allow the user to tap the pin to start an action. Now - I would like, on tap, to show information from the object that relates to that pin to be shown in a textbox. How can I retrieve the object from the array that corresponds to the pushpin that was tapped/clicked? foreach (wikiResult result in arrayResults) { double lat = double.Parse(result.Latitude, CultureInfo.InvariantCulture); double lng = double.Parse(result.Longitude, CultureInfo.InvariantCulture); statusTextBlock.Text = result.Latitude + " " + result.Longitude + " " + lat + " " + lng; GeoCoordinate d = new GeoCoordinate(lat, lng); Pushpin pin; pin = new Pushpin(); pin.Location = d; pin.Content = result.Name; pin.MouseLeftButtonUp += new MouseButtonEventHandler(pin1_MouseLeftButtonUp); myMap.Children.Add(pin); } void pin1_MouseLeftButtonUp(object sender, MouseButtonEventArgs e) { //display the content from the object in a text box } Many thanks in advance!

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  • need help about process........

    - by adeel amin
    when i start process like process= Runtime.getRuntime().exec("gnome-terminal");, it start shell execution, i want to stop shell execution and want to redirect I/O from process, can anybody tell how i can do this? my code is: public void start_process() { try { process= Runtime.getRuntime().exec("bash"); pw= new PrintWriter(process.getOutputStream(),true); br=new BufferedReader(new InputStreamReader(process.getInputStream())); err=new BufferedReader(new InputStreamReader(process.getErrorStream())); } catch (Exception ioe) { System.out.println("IO Exception-> " + ioe); } } public void execution_command() { if(check==2) { try { boolean flag=thread.isAlive(); if(flag==true) thread.stop(); Thread.sleep(30); thread = new MyReader(br,tbOutput,err,check); thread.start(); }catch(Exception ex){ JOptionPane.showMessageDialog(null, ex.getMessage()+"1"); } } else { try { Thread.sleep(30); thread = new MyReader(br,tbOutput,err,check); thread.start(); check=2; }catch(Exception ex){ JOptionPane.showMessageDialog(null, ex.getMessage()+"1"); } } } private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) { // TODO add your handling code here: command=tfCmd.getText().toString().trim(); pw.println(command); execution_command(); } when i enter some command in textfield and press execute button, nothing displayed on my output textarea, how i can stop shellexecution and can redirect Input and output?

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  • Dynamic Control loading at wrong time?

    - by Telos
    This one is a little... odd. Basically I have a form I'm building using ASP.NET Dynamic Data, which is going to utilize several custom field templates. I've just added another field to the FormView, with it's own custom template, and the form is loading that control twice for no apparent reason. Worse yet, the first time it loads the template, the Row is not ready yet and I get the error message: {"Databinding methods such as Eval(), XPath(), and Bind() can only be used in the context of a databound control."} I'm accessing the Row variable in a LinqDataSource OnSelected event in order to get the child object... Now for the wierd part: If I reorder the fields a little, the one causing the problem no longer gets loaded twice. Any thoughts? EDIT: I've noticed that Page_Load gets called on the first load (when Row throws an exception if you try to use it) but does NOT get called the second time around. If that helps any... Right now managing it by just catching and ignoring the exception, but still a little worried that things will break if I don't find the real cause. EDIT 2: I've traced the problem to using FindControl recursively to find other controls on the page. Apparently FindControl can cause the page lifecycle events (at least up to page_load) to fire... and this occurs before that page "should" be loading so it's dynamic data "stuff" isn't ready yet.

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  • Validation L2S question

    - by user158020
    This may be a bit winded because I am new to wpf. I have created a partial class for an entity in my L2S class that is primarily used for validation. It implements the onchanging and onvalidate methods. I am trying to use the MVVM pattern, and in a window/view I have set the datacontext in the xaml: <Window.DataContext> <vm:StartViewModel /> </Window.DataContext> when a user leaves a required field in the view blank, the onchanging event of the partial class is fired when I close the form, not when I save the data. So, if a user leaves the textbox blank, the old value is retained and the onchaging method is fired, but I have no idea how to alert the user of the resulting error. here is my onchanging code in the partial class: partial void Ondocument_titleChanging(string value) { if (value.Length == 0) throw new Exception("Document title is required."); if (value.Length > 256) throw new Exception("Document title cannot be longer than 256 characters."); } throwing an exception doesn't notify the user of the error. it just allows the form to close and rejects the changes to the textbox. hope this makes sense... edit: this example was taken from Scott Guthries article here: http://aspalliance.com/1427_LINQ_to_SQL_Part_5__Binding_UI_using_the_ASPLinqDataSource_Control.5

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  • Run a flash movie in flex application.

    - by Irwin
    I've a flash movie that I would like to use inside of a flex application, very similar to a preloader. Looking at this tutorial, http://www.flexer.info/2008/02/07/very-first-flex-preloader-customization/, I expected it would be a matter of not extending "Preloader" and extending "Sprite" and using the class i created wherever i needed. Alas, the movie I created, is not being shown. This is the code for my class containing the movie, made based on the tutorial above: package { import mx.preloaders.DownloadProgressBar; import flash.display.Sprite; import flash.events.ProgressEvent; import flash.events.Event; import mx.events.FlexEvent; import flash.display.MovieClip; public class PlayerAnimation extends Sprite { [Embed("Player.swf")] public var PlayerGraphic:Class; public var mc:MovieClip; public function PlayerAnimation():void { super(); mc = new PlayerGraphic(); addChild(mc); } public function Play():void { mc.gotoAndStop(2); } } }

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  • Databinding Textbox to Form.Text (title)

    - by MysticEarth
    I'm trying to bind a Textbox.Text to Form.Text (which sets the title of the form). The binding itself works. But, the title isn't updated until I move the entire form. How can I achieve Form.Text being updated without moving the form? I'd like Form.Text being updated directly when I type something in the Textbox. Edit; I set the title of the Form in a TextChanged event which is fired by a ToolStripTextbox: public partial class ProjectForm : Form { public ProjectForm() { // my code contains all sorts of code here, // but nothing that has something to do with the text. } } private void projectName_TextChanged_1(object sender, EventArgs e) { this.Text = projectName.TextBox.Text; } And the Databinding version: public partial class ProjectForm : Form { public ProjectForm() { this.projectName.TextBox.DataBindings.Add("Text", this, "Text", true, DataSourceUpdateMode.OnValidation); } } Edit 2: I see I forgot to mention something. Don't know if it adds anything, but my apllication is a MDI application. The part of the title that changes is: ApplicationName [THIS CHANGES, BUT ONLY AFTER MOVING/RESIZING]

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  • Can threads safely read variables set by VCL events?

    - by Tom1952
    Is it safe for a thread to READ a variable set by a Delphi VCL event? When a user clicks on a VCL TCheckbox, the main thread sets a boolean to the checkbox's Checked state. CheckboxState := CheckBox1.Checked; At any time, a thread reads that variable if CheckBoxState then ... It doesn't matter if the thread "misses" a change to the boolean, because the thread checks the variable in a loop as it does other things. So it will see the state change eventually... Is this safe? Or do I need special code? Is surrounding the read and write of the variable (in the thread and main thread respectively) with critical code calls necessary and sufficient? As I said, it doesn't matter if the thread gets the "wrong" value, but I keep thinking that there might be a low-level problem if one thread tries to read a variable while the main thread is in the middle of writing it, or vice versa. My question is similar to this one: http://stackoverflow.com/questions/1353096/cross-thread-reading-of-a-variable. (Also related to my previous question: http://stackoverflow.com/questions/2449183/using-entercriticalsection-in-thread-to-update-vcl-label)

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  • Custom pager in my Gridview 1st time works, next doesn't :

    - by gre3ns0ul
    Hi guys, i'm with one strange problem. I am extending a control from a Gridview, and adding a dropdown to paging to the page i want. In my custom gridview i added a ITemplate than contains 4 image buttons and one dropdownlist (4 images - 1st, prev, next, last) (1 ddl - to page) and add him to my custom gridview.. I added a selectindexchange event to dropdown, to fire when a index is changed The problem is: The first time i load the page with my control it is really ok.. but when i change index, in debug i see to run constructor of control, creating footer template, and guess.. the method of indexchange isn't fired and returns an exception saying: Unable to cast object of type 'System.Web.UI.WebControls.ImageButton' to type 'System.Web.UI.WebControls.Table'. [InvalidCastException: Unable to cast object of type 'System.Web.UI.WebControls.ImageButton' to type 'System.Web.UI.WebControls.Table'.] System.Web.UI.WebControls.GridView.PrepareControlHierarchy() +122 System.Web.UI.WebControls.GridView.Render(HtmlTextWriter writer, Boolean renderPanel) +50 System.Web.UI.WebControls.GridView.Render(HtmlTextWriter writer) +33 System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27 System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99 System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25 System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +134 System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19 System.Web.UI.Control.Render(HtmlTextWriter writer) +10 ... apreciate for the help, thanks

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  • How to Read Device Data From serial port

    - by Aamir Khurshid
    I have one device which sends data on COM port say on COM13. Now i want to read that data and display it in the RichTextBox or in any text control. I have written the application with the help of IO and IO.Ports but comport.DataRecived event does not fire, even though device is sending data on that port. I have some software on which i define the port number and it successfully display data, which insure me that data is receiving on the Port but i am unable to receive. Is there any way i can read data? comm.Parity = cboParity.Text;//None comm.StopBits = cboStop.Text;//One comm.DataBits = cboData.Text;//8 comm.BaudRate = cboBaud.Text;//9600 comm.DisplayWindow = rtbDisplay;//Null comm.PortName = "COM13"; comm.OpenPort(); cmdOpen.Enabled = false; cmdClose.Enabled = true; cmdSend.Enabled = true; public bool OpenPort() { if (comPort.IsOpen) { comPort.Close(); } comPort.DataReceived += new SerialDataReceivedEventHandler(comPort_DataReceived); comPort.PortName = _portName; comPort.Open();return true; }

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  • UITouch Events and Table Views

    - by Andy
    I'm working on a navigation-based iPhone-only app that serves two main purposes: One, to present data in a hierarchical view, allowing users to drill down and eventually edit said data, and, two, to all users to perform a default action when the table view cell is tapped. I now need to offer a small set of options tied to the same data; however, both the didSelectRowAtIndexPath: and accessoryButtonTappedForRowAtIndexPath: methods are obviously taken. So, my options seem to be to implement a double-tap method, wherein the small list of additional options would be presented after (you guessed it) a double-tap on said table row; or, preferably, a tap-and-hold method. From what I can tell, tap-and-hold seems like the way to go in SDK 4.0 - which does me no good right this red-hot minute. I decided to go with the double-tap option, but I'm having a little trouble. First and foremost, the touchesBegan:withEvent: method does not seem to be getting called at all; a breakpoint placed within the method is never called while the application runs, and the table view responds exactly as it did before I inserted the method (which is to say, it performs the default action): - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { UITouch *aTouch = [touches anyObject]; if (aTouch.tapCount == 2) { [NSObject cancelPreviousPerformRequestsWithTarget:self]; } } Second, I don't really need to handle a single-tap - the didSelectRowAtIndexPath: method can handle the single-tap just fine. The double-tap is the funky one I want to handle. I suspect the answer is going to contain the phrase, "You can't have the table view handle the single-tap and the touchesBegan: method handle the double-tap. The touch handling methods have to handle all of them." I would really appreciate some guidance from some of you who've dealt with this issue. Thanks in advance.

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  • how to make the printer window appear using vb.net 2010

    - by Jeline Esase
    hi I have this code that will send my panel into a printer but the problem is it doesent let me choose which printer I will use any idea on how can I make the printer window appear? thanks Public Class Form1 Dim img As Bitmap Dim WithEvents pd As PrintDocument 'Returns the Form as a bitmap Function CaptureForm1() As Bitmap Dim g1 As Graphics = Me.CreateGraphics() Dim MyImage = New Bitmap(Me.ClientRectangle.Width, (Me.ClientRectangle.Height), g1) Dim g2 As Graphics = Graphics.FromImage(MyImage) Dim dc1 As IntPtr = g1.GetHdc() Dim dc2 As IntPtr = g2.GetHdc() BitBlt(dc2, 0, 0, Me.ClientRectangle.Width, (Me.ClientRectangle.Height), dc1, 0, 0, 13369376) g1.ReleaseHdc(dc1) g2.ReleaseHdc(dc2) 'saves image to c drive just, u can comment it also 'MyImage.Save("c:\abc.bmp") Return MyImage End Function <DllImport("gdi32.DLL", EntryPoint:="BitBlt", _ SetLastError:=True, CharSet:=CharSet.Unicode, _ ExactSpelling:=True, _ CallingConvention:=CallingConvention.StdCall)> _ Private Shared Function BitBlt(ByVal hdcDest As IntPtr, ByVal nXDest As Integer, ByVal nYDest As Integer, ByVal nWidth As Integer, ByVal nHeight As Integer, ByVal hdcSrc As IntPtr, ByVal nXSrc As Integer, ByVal nYSrc As Integer, ByVal dwRop As System.Int32) As Boolean ' Leave function empty - DLLImport attribute forwards calls to MoveFile to ' MoveFileW in KERNEL32.DLL. End Function Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click img = CaptureForm1() pd = New PrintDocument pd.Print() End Sub 'this method will be called each time when pd.printpage event occurs Sub pd_PrintPage(ByVal sender As Object, ByVal e As PrintPageEventArgs) Handles pd.PrintPage Dim x As Integer = e.MarginBounds.X Dim y As Integer = e.MarginBounds.Y e.Graphics.DrawImage(img, x, y) e.HasMorePages = False End Sub End Class

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