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  • Alpha issue with SharpDX SpriteBatch in WPF

    - by Kingdom
    .Hi devs, I'm coding a game using SharpDX in a WPF context. void Load() { sb = new SpriteBatch(GraphicsDevice); t2d = Content.Load<Texture2D>("Sprite.png"); } void Draw() { sb.Begin(); sb.Draw(t2d, new Rectangle(0, 0, 64, 64), Color.White); sb.End(); } I made Sprite.png, an object with pink color (alpha = 0%) for the background. The output show me my object but with the pink square at more or less 50% rate! So if I try to draw more sprites, it's like a little poney dream. Note If I apply Color.Black on the Draw method, the sprite is like expected :|

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  • IntelliTrace Causing Slow WPF Debugging in Visual Studio 2010

    - by WeigeltRo
    Just a quick note to myself (and others that may stumble across this blog entry via a web search): If a WPF application is running slow inside the debugger of Visual Studio 2010, but perfectly fine without a debugger (e.g. by hitting Ctrl-F5), then the reason may be Intellitrace. In my case switching off Intellitrace (only available in the Ultimate Edition of Visual Studio 2010) helped gitting rid of the sluggish behavior of a DataGrid. In the “Tools” menu select “Options”, on the Options dialog click “Intellitrace” and then uncheck “Enable Intellitrace”. Note that I do not have access to Visual Studio 2012 at the time of this writing, thus I cannot make a statement about its debugging behavior.

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  • Databinding to an Entity Framework in WPF

    - by King Chan
    Is it good to use databinding to Entity Framework's Entity in WPF? I created a singleton entity framework context: To have only one connection and it won't open and close all the time. So I can pass the Entity around to any class, and can modify the Entity and make changes to the database. All ViewModels getting the entity out from the same Context and databinding to the View saves me time from mapping new object, but now I imagine there is problem in not using the newest Context: A ViewModel databinding to a Entity, then someone else updated the data. The ViewModel will still display the old data, because the Context is never being dispose to refresh. I always create new Context and then dispose of it. If I want to pass the Entity around, then there will be conflicts between Context and Entity. What is the suggested way of doing this ?

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  • Should I start learning WPF?

    - by questron
    Hi, I've been studying C# for about 2 months so far, I have a few years experience programming however in VBA and VB6, but nothing too in depth (I've written simple tools, but nothing too advanced). I am very interested in WPF and I was wondering whether it would be too early for me to start learning how to use it? For reference, I am about 400 pages into 'Head First C#' and I've written a program that can quickly tag image files for moving into a predefined folder or to delete (Allows the user to pull images off of a camera memory card and sort VERY quickly). That's the most advanced app I've written.

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  • WPF DataGrid and Avalon TimePicker binding problem

    - by Jorge Vargas
    I'm using a the WPF DataGrid from the wpf toolkit and a TimePicker from AvalonControlsLibrary to insert a collection of TimeSpans. My problem is that bindings are not working inside the DataGrid, and I have no clue of why this isn't working. Here is my setup: I have the following XAML: <Window x:Class="Views.TestMainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:wpf="http://schemas.microsoft.com/wpf/2008/toolkit" xmlns:a="http://schemas.AvalonControls/AvalonControlsLibrary/Controls" SizeToContent="WidthAndHeight" MinHeight="250" MinWidth="300"> <Grid> <Grid.RowDefinitions> <RowDefinition Height="*" /> <RowDefinition Height="Auto" /> </Grid.RowDefinitions> <GroupBox Grid.Row="0"> <GroupBox.Header> Testing it: </GroupBox.Header> <wpf:DataGrid ItemsSource="{Binding Path=TestSpans}" AutoGenerateColumns="False"> <wpf:DataGrid.Columns> <wpf:DataGridTemplateColumn Header="Start"> <wpf:DataGridTemplateColumn.CellEditingTemplate> <DataTemplate> <a:TimePicker SelectedTime="{Binding Path=., Mode=TwoWay}" /> </DataTemplate> </wpf:DataGridTemplateColumn.CellEditingTemplate> <wpf:DataGridTemplateColumn.CellTemplate> <DataTemplate> <TextBlock Text="{Binding}" /> </DataTemplate> </wpf:DataGridTemplateColumn.CellTemplate> </wpf:DataGridTemplateColumn> </wpf:DataGrid.Columns> </wpf:DataGrid> </GroupBox> <StackPanel Orientation="Horizontal" HorizontalAlignment="Right" Grid.Row="1"> <a:TimePicker SelectedTime="{Binding Path=SelectedTime, Mode=TwoWay}" /> </StackPanel> </Grid> And this is my ViewModel: Imports System.Collections.ObjectModel Namespace ViewModels Public Class TestMainWindowViewModel Private _selectedTime As TimeSpan = DateTime.Now.TimeOfDay Public Property SelectedTime() As TimeSpan Get Return _selectedTime End Get Set(ByVal value As TimeSpan) _selectedTime = value End Set End Property Private _testSpans As ObservableCollection(Of TimeSpan) = New ObservableCollection(Of TimeSpan) Public Property TestSpans() As ObservableCollection(Of TimeSpan) Get Return _testSpans End Get Set(ByVal value As ObservableCollection(Of TimeSpan)) _testSpans = value End Set End Property Public Sub New() _testSpans.Add(DateTime.Now.TimeOfDay) _testSpans.Add(DateTime.Now.TimeOfDay) _testSpans.Add(DateTime.Now.TimeOfDay) End Sub End Class End Namespace I'm starting this window in application.xaml.vb like this: Class Application ' Application-level events, such as Startup, Exit, and DispatcherUnhandledException ' can be handled in this file. Protected Overrides Sub OnStartup(ByVal e As System.Windows.StartupEventArgs) MyBase.OnStartup(e) Dim window As Views.TestMainWindow = New Views.TestMainWindow window.DataContext = New TestMainWindowViewModel() window.Show() End Sub End Class

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  • Screenshot from WPF application as SVG / vector graphic?

    - by stefan.at.wpf
    Hello, is it possible to create a screenshot of a WPF application as SVG / is there some WPF built-in function to get the XAML code for the current drawn window that then can be converted to SVG? I need some screenshots for documenting a WPF application and I'd like them to be zoomable like a WPF program is using e.g. Snoop or Vista Magnifyer. Thanks for any hint!

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  • Set focus on textbox in WPF from view model (C#) & wPF

    - by priyanka.sarkar
    I have a TextBox and a Button in my view. Now I am checking a condition upon button click and if the condition turns out to be false, displaying the message to the user, and then I have to set the cursor to the text box control. if (companyref == null) { Lipper.Nelson.AdminClient.Main.Views.ContactPanels.CompanyAssociation cs = new Lipper.Nelson.AdminClient.Main.Views.ContactPanels.CompanyAssociation(); MessageBox.Show("Company does not exist.", "Error", MessageBoxButton.OK, MessageBoxImage.Exclamation); cs.txtCompanyID.Focusable = true; System.Windows.Input.Keyboard.Focus(cs.txtCompanyID); } The above code is in the view model. The CompanyAssociation is the view name. But the cursor is not getting set in the TextBox. The xaml is as under <igEditors:XamTextEditor KeyDown="xamTextEditorAllowOnlyNumeric_KeyDown" Name="txtCompanyID" ValueChanged="txtCompanyID_ValueChanged" Text="{Binding Company.CompanyId, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" Width="{Binding ActualWidth, ElementName=border}" Grid.Column="1" Grid.Row="0" VerticalAlignment="Top" Margin="0,5,0,0" HorizontalAlignment="Stretch" IsEnabled="{Binding Path=IsEditable}" /> <Button Template="{StaticResource buttonTemp1}" Command="{Binding ContactCommand}" CommandParameter="searchCompany" Content="Search" Width="80" Grid.Column="2" Grid.Row="0" VerticalAlignment="Top" Margin="0" HorizontalAlignment="Left" IsEnabled="{Binding Path=IsEditable}" /> Please help

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  • WPF: Sort of inconsistence in the visual appearence of WPF controls derived by Selector class

    - by msfanboy
    Hello, focused items == selected items but selected items != focused items. Have you ever wondered about that? Do you specially style the backcolor of a focused/selected item ? I ask this question because a user has an enabled button because some customer items are selected. The user is wondering now "why the heck can I delete this customers (button is enabled...) when I have just clicked on the orders control selecting some orders ready to delete (button is enabled too). The thing is the selected customer items are nearly looking grayed out in the default style... Well its sort of inconsistence to the user NOT to the programmer because WE know the behavior. Do you cope with stuff like that?

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  • Making a C# w/ WPF multiple frame text / pseudo-calendar GUI application [closed]

    - by Gregor Samsa
    I am editing a recently asked question and making it specific, taking the advice of some people here. I would like to program of the following simple form: The user can produce X number of resizable frames (analogous to HTML frames). Each frame serves as a simple text editor, which you can type into and save the whole configuration including resized windows and text. The user should be able alternately "freeze" and present the information, and "unfreeze" and edit frames. I want to use C## with WPF, in Microsoft's Visual C#. I do not yet know this language. I am sure I can pick up the syntax, but I would like to ask about some general advice for how to structure such a program. I have never made a GUI program, let alone one that interfaces with a notepad or some basic text editor. Can someone either direct me to a good resource that will teach me how to do the above? Or outline the basic ingredients that such a program will require, keeping in mind that though I know some C and Python, I have no experience with GUIs or advanced programming generally? In particular I don't know how to incorporate this "text editor" aspect of the program, as well as the resizable frames I would greatly appreciate any help.

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  • an enter key are handled twice in WPF/Winform mixed project

    - by user527403
    I have a winform dashboard which hosts some WPF dialogs. When I select a row in the winform ListView and hit Enter key, OnItemActivate is called which launches a WPF dialog. However, the WPF dialog appears and then disappears immediately because the default button “cancel” is hit. It seems that the Enter key is triggered twice, one for launching the WPF dialog, the other for hitting cancel button. We don’t want the WPF dialog to be canceled by the Enter key hitting. According to the stack trace, it looks like that WPF and Winform handle the enter key separately. The WPF does not know that the enter key has been handled by the Winform ListView. Is this by design in Winform and WPF interop? To make the enter key not close the WPF dialog, we have to change the focus from the cancel button to another control (e.g. a textblock). Is there a better way to fix/around this issue?

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  • WPF TextBlock refresh in real time

    - by TheOnlyBrien
    I'm new to C#, in fact, this is one of the first projects I've tried to start on my own. I am curious why the TextBlock will not refresh with the following code? The WPF window does not even show up when I add the "while" loop to the code. I just want this to have a real time display of the days since I was born. Please help me out or give me constructive direction. using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows; using System.Windows.Controls; using System.Windows.Data; using System.Windows.Documents; using System.Windows.Input; using System.Windows.Media; using System.Windows.Media.Imaging; using System.Windows.Navigation; using System.Windows.Shapes; namespace daysAliveWPF { /// <summary> /// Interaction logic for MainWindow.xaml /// </summary> public partial class MainWindow : Window { public MainWindow() { InitializeComponent(); DateTime myBirthday = new DateTime(1984, 01, 19); while (true) { TimeSpan daysAlive = DateTime.Now.Subtract(myBirthday); MyTextBlock.Text = daysAlive.TotalDays.ToString(); } } } } Similar code has worked in a Console Window application, so I don't understand what's going on here. Console Application code snip that did work is: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace DisplayRealTime { class Program { static void Main(string[] args) { DateTime myBirthday = new DateTime(1984, 06, 19); while (true) { TimeSpan daysAlive = DateTime.Now.Subtract(myBirthday); Console.Write("\rTotal Days Alive: {0}", daysAlive.TotalDays.ToString(".#####")); } } } } Thank you!

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  • What is a good alternative to the WPF WebBrowser Control?

    - by VoidDweller
    I have an MDI WPF app that I need to add web content to. At first, great it looks like I have 2 options built into the framework the Frame control and the WebBrowser control. Given that this is an MDI app it doesn't take long to discover that neither of these will work. The WPF WebBrowser control wraps up the IE WebBrowser ActiveX Control which uses the Win32 graphics pipeline. The "Airspace" issue pretty much sums this up as "Sorry, the layouts will not play nice together". Yes, I have thought about taking snapshots of the web content rendering these and mapping the mouse and keyboard events back to the browser control, but I can't afford the performance penalty and I really don't have time to write and thoroughly test it. I have looked for third party controls, but so far I have only found Chris Cavanagh's WPF Chromium Web Browser control. Which wraps up Awesomium 1.5. Together these are very cool, they play nice with the WPF layouts. But they do not meet my performance requirements. They are VERY HEAVY on memory consumption and not to friendly with CPU usage either. Not to mention still quite buggy. I'll elaborate if you are interested. So, do any of you know of a stable performant WPF web browser control? Thanks.

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  • How do I pass arguments to pages in a WPF application?

    - by Rod
    I'm working on upgrading a really old VB6 app to a WPF application. This will be a page-based app, but not a XBAP. The old VB6 app had a start form where a user would enter search criteria. Then they would get results in a grid, select a row in the grid and then click on one of 3 buttons. I am thinking that what I'll do is use hyperlink controls on the WPF app. No matter what button the user clicked on the old VB6 app, it would go to a second form. What it did on the second form was dependent upon which button the user clicked on the first form. So, I want the first page in my WPF app to do the same thing, but depending upon which hyperlink they click on will dictate what happens on the second page. They will either (a) go to the second page to edit the details as well as a lot more information, related to what they selected on the first page, or (b) enter a new record and all associated data (a new client, in this case), or (c) create a new case for the same client, selected on the first page. For me the hard thing is I don't know how to pass that information along to the second page. Is there something in WPF like in HTML where there's a query string? Or how do you get information from the first page to the second page, in WPF? I'm working in VS 2008.

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  • WPF ListView as a DataGrid – Part 3

    - by psheriff
    I have had a lot of great feedback on the blog post about turning the ListView into a DataGrid by creating GridViewColumn objects on the fly. So, in the last 2 parts, I showed a couple of different methods for accomplishing this. Let’s now look at one more and that is use Reflection to extract the properties from a Product, Customer, or Employee object to create the columns. Yes, Reflection is a slower approach, but you could create the columns one time then cache the View object for re-use. Another potential drawback is you may have columns in your object that you do not wish to display on your ListView. But, just because so many people asked, here is how to accomplish this using Reflection.   Figure 1: Use Reflection to create GridViewColumns. Using Reflection to gather property names is actually quite simple. First you need to pass any type (Product, Customer, Employee, etc.) to a method like I did in my last two blog posts on this subject. Below is the method that I created in the WPFListViewCommon class that now uses reflection. C#public static GridView CreateGridViewColumns(Type anyType){  // Create the GridView  GridView gv = new GridView();  GridViewColumn gvc;   // Get the public properties.  PropertyInfo[] propInfo =          anyType.GetProperties(BindingFlags.Public |                                BindingFlags.Instance);   foreach (PropertyInfo item in propInfo)  {    gvc = new GridViewColumn();    gvc.DisplayMemberBinding = new Binding(item.Name);    gvc.Header = item.Name;    gvc.Width = Double.NaN;    gv.Columns.Add(gvc);  }   return gv;} VB.NETPublic Shared Function CreateGridViewColumns( _  ByVal anyType As Type) As GridView  ' Create the GridView   Dim gv As New GridView()  Dim gvc As GridViewColumn   ' Get the public properties.   Dim propInfo As PropertyInfo() = _    anyType.GetProperties(BindingFlags.Public Or _                          BindingFlags.Instance)   For Each item As PropertyInfo In propInfo    gvc = New GridViewColumn()    gvc.DisplayMemberBinding = New Binding(item.Name)    gvc.Header = item.Name    gvc.Width = [Double].NaN    gv.Columns.Add(gvc)  Next   Return gvEnd Function The key to using Relection is using the GetProperties method on the type you pass in. When you pass in a Product object as Type, you can now use the GetProperties method and specify, via flags, which properties you wish to return. In the code that I wrote, I am just retrieving the Public properties and only those that are Instance properties. I do not want any static/Shared properties or private properties. GetProperties returns an array of PropertyInfo objects. You can loop through this array and build your GridViewColumn objects by reading the Name property from the PropertyInfo object. Build the Product Screen To populate the ListView shown in Figure 1, you might write code like the following: C#private void CollectionSample(){  Product prod = new Product();   // Setup the GridView Columns  lstData.View =      WPFListViewCommon.CreateGridViewColumns(typeOf(Product));  lstData.DataContext = prod.GetProducts();} VB.NETPrivate Sub CollectionSample()  Dim prod As New Product()   ' Setup the GridView Columns  lstData.View = WPFListViewCommon.CreateGridViewColumns( _       GetType(Product))  lstData.DataContext = prod.GetProducts()End Sub All you need to do now is to pass in a Type object from your Product class that you can get by using the typeOf() function in C# or the GetType() function in VB. That’s all there is to it! Summary There are so many different ways to approach the same problem in programming. That is what makes programming so much fun! In this blog post I showed you how to create ListView columns on the fly using Reflection. This gives you a lot of flexibility without having to write extra code as was done previously. NOTE: You can download the complete sample code (in both VB and C#) at my website. http://www.pdsa.com/downloads. Choose Tips & Tricks, then "WPF ListView as a DataGrid – Part 3" from the drop-down. Good Luck with your Coding,Paul Sheriff ** SPECIAL OFFER FOR MY BLOG READERS **Visit http://www.pdsa.com/Event/Blog for a free eBook on "Fundamentals of N-Tier".  

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  • Is it possible to write a class that interacts with controls on my WPF form?

    - by Adam S
    Hi all, I'm trying to write a class that I can use to interact with a group of similar controls in my wpf application. I have hit a few roadblocks and now I am wondering if this is a poor approach to begin with. I want to do this primarily to make my code more manageable - I have to interact with around 200 - 300 controls with my code, and it could get very tricky to have all my code in the main window class. Here's something I'd like to be able to do: class ProcControl { private CheckBox * [] Boxes = new CheckBox[10]; ProcControl() { //set boxes 0-9 to point to the actual checkboxes } //provides mass checking/unchecking functionality public void Refactor(CheckBox box) { //see what box it is int box_index = 0; while (Boxes[box_index] != box) { box_index++; } } } This doesn't work as it is right now. I have not figured out how to get my Boxes[] array to point to the actual checkboxes on my form, so I can't interact with them yet. Is it even possible to make an array that points to a bunch of controls so that I may process their properties in a nice manner? Why can't I access the controls at all from inside my class?

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  • WPF - Why doesn't Microsoft supply a decent set of most-used controls ?

    - by IUsedToBeAPygmy
    I've been playing with WPF for some months now, and I quite like it. But one of the things I don't get is why MS doesn't put a little more effort in helping developers by supplying basic controls, and I need to get this off my chest :) For example, I figure most applications somewhere will need to let you edit some properties - for configuration or whatever. What would be the most used types in a proprety-grid editor ? text numbers (byte, float/double, int, etc) colors ....etc. So why isn't there even something as simple as a control to edit numbers ? Like a generic NumericUpDown control that allows you to type in numbers (no text, no pasting invalid input) or spin them up/down according to some given rules (decimal, floating point, min/maxvalue) ? Why isn't there a generic colorpicker, so people get the same user-experience in every application ? Why isn't there a standard implementation of a SearchTextBox, a BreadCrumb-control, or all these other standard control types users have gotten accustomed to the last 10 years ? (..but at least they DID have the time to implement a generic splashscreen - because everyone knows that greatly increases user-productivity....) The well-known ideal is always to give people the same user-experience over different applications. So even if some of those controls would be easy to make - it would be preferred to have one version over different applications. I see people all over the internet trying to do the same stuff over and over again. Okay, so MS started a WPF Toolkit project on Codeplex that tries to implement some controls, but only did so half-heartedly and is completely dead by now (last update of the roadmap dates back to Mar 21 2009). The result of this is that a lot of people starting a WPF-project end up spending a lot of time on trying to figure out how to create some generic controls and get really frustrated. Wasn't the mantra "Developers, developers, developers!" ..? /Rant

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  • Of WPF and Winforms, which is the better skills to have in the job market?

    - by CraigJ
    I have a large VB6 desktop app which I would like to upgrade to .NET in order to take advantage of the newer .NET API. I am at a loose end as to whether to adopt WPF or Winforms when creating the new .NET solution. I realise that WPF seems to be in some ways the successor of Winforms. The only thing stopping me taking on WPF for this project is my concern that when the project has been completed the job marketplace will still be calling for Winforms skills and not necessarily WPF. Is this a valid concern? Note: I am aware there are existing questions on "WPF vs Winforms" generally, but this question relates to my specific concern about the job market.

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  • Launching a WPF Window in a Separate Thread, Part 1

    - by Reed
    Typically, I strongly recommend keeping the user interface within an application’s main thread, and using multiple threads to move the actual “work” into background threads.  However, there are rare times when creating a separate, dedicated thread for a Window can be beneficial.  This is even acknowledged in the MSDN samples, such as the Multiple Windows, Multiple Threads sample.  However, doing this correctly is difficult.  Even the referenced MSDN sample has major flaws, and will fail horribly in certain scenarios.  To ease this, I wrote a small class that alleviates some of the difficulties involved. The MSDN Multiple Windows, Multiple Threads Sample shows how to launch a new thread with a WPF Window, and will work in most cases.  The sample code (commented and slightly modified) works out to the following: // Create a thread Thread newWindowThread = new Thread(new ThreadStart( () => { // Create and show the Window Window1 tempWindow = new Window1(); tempWindow.Show(); // Start the Dispatcher Processing System.Windows.Threading.Dispatcher.Run(); })); // Set the apartment state newWindowThread.SetApartmentState(ApartmentState.STA); // Make the thread a background thread newWindowThread.IsBackground = true; // Start the thread newWindowThread.Start(); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } This sample creates a thread, marks it as single threaded apartment state, and starts the Dispatcher on that thread. That is the minimum requirements to get a Window displaying and handling messages correctly, but, unfortunately, has some serious flaws. The first issue – the created thread will run continuously until the application shuts down, given the code in the sample.  The problem is that the ThreadStart delegate used ends with running the Dispatcher.  However, nothing ever stops the Dispatcher processing.  The thread was created as a Background thread, which prevents it from keeping the application alive, but the Dispatcher will continue to pump dispatcher frames until the application shuts down. In order to fix this, we need to call Dispatcher.InvokeShutdown after the Window is closed.  This would require modifying the above sample to subscribe to the Window’s Closed event, and, at that point, shutdown the Dispatcher: // Create a thread Thread newWindowThread = new Thread(new ThreadStart( () => { Window1 tempWindow = new Window1(); // When the window closes, shut down the dispatcher tempWindow.Closed += (s,e) => Dispatcher.CurrentDispatcher.BeginInvokeShutdown(DispatcherPriority.Background); tempWindow.Show(); // Start the Dispatcher Processing System.Windows.Threading.Dispatcher.Run(); })); // Setup and start thread as before This eliminates the first issue.  Now, when the Window is closed, the new thread’s Dispatcher will shut itself down, which in turn will cause the thread to complete. The above code will work correctly for most situations.  However, there is still a potential problem which could arise depending on the content of the Window1 class.  This is particularly nasty, as the code could easily work for most windows, but fail on others. The problem is, at the point where the Window is constructed, there is no active SynchronizationContext.  This is unlikely to be a problem in most cases, but is an absolute requirement if there is code within the constructor of Window1 which relies on a context being in place. While this sounds like an edge case, it’s fairly common.  For example, if a BackgroundWorker is started within the constructor, or a TaskScheduler is built using TaskScheduler.FromCurrentSynchronizationContext() with the expectation of synchronizing work to the UI thread, an exception will be raised at some point.  Both of these classes rely on the existence of a proper context being installed to SynchronizationContext.Current, which happens automatically, but not until Dispatcher.Run is called.  In the above case, SynchronizationContext.Current will return null during the Window’s construction, which can cause exceptions to occur or unexpected behavior. Luckily, this is fairly easy to correct.  We need to do three things, in order, prior to creating our Window: Create and initialize the Dispatcher for the new thread manually Create a synchronization context for the thread which uses the Dispatcher Install the synchronization context Creating the Dispatcher is quite simple – The Dispatcher.CurrentDispatcher property gets the current thread’s Dispatcher and “creates a new Dispatcher if one is not already associated with the thread.”  Once we have the correct Dispatcher, we can create a SynchronizationContext which uses the dispatcher by creating a DispatcherSynchronizationContext.  Finally, this synchronization context can be installed as the current thread’s context via SynchronizationContext.SetSynchronizationContext.  These three steps can easily be added to the above via a single line of code: // Create a thread Thread newWindowThread = new Thread(new ThreadStart( () => { // Create our context, and install it: SynchronizationContext.SetSynchronizationContext( new DispatcherSynchronizationContext( Dispatcher.CurrentDispatcher)); Window1 tempWindow = new Window1(); // When the window closes, shut down the dispatcher tempWindow.Closed += (s,e) => Dispatcher.CurrentDispatcher.BeginInvokeShutdown(DispatcherPriority.Background); tempWindow.Show(); // Start the Dispatcher Processing System.Windows.Threading.Dispatcher.Run(); })); // Setup and start thread as before This now forces the synchronization context to be in place before the Window is created and correctly shuts down the Dispatcher when the window closes. However, there are quite a few steps.  In my next post, I’ll show how to make this operation more reusable by creating a class with a far simpler API…

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  • WPF ListView as a DataGrid – Part 2

    - by psheriff
    In my last blog post I showed you how to create GridViewColumn objects on the fly from the meta-data in a DataTable. By doing this you can create columns for a ListView at runtime instead of having to pre-define each ListView for each different DataTable. Well, many of us use collections of our classes and it would be nice to be able to do the same thing for our collection classes as well. This blog post will show you one approach for using collection classes as the source of the data for your ListView.  Figure 1: A List of Data using a ListView Load Property NamesYou could use reflection to gather the property names in your class, however there are two things wrong with this approach. First, reflection is too slow, and second you may not want to display all your properties from your class in the ListView. Instead of reflection you could just create your own custom collection class of PropertyHeader objects. Each PropertyHeader object will contain a property name and a header text value at a minimum. You could add a width property if you wanted as well. All you need to do is to create a collection of property header objects where each object represents one column in your ListView. Below is a simple example: PropertyHeaders coll = new PropertyHeaders(); coll.Add(new PropertyHeader("ProductId", "Product ID"));coll.Add(new PropertyHeader("ProductName", "Product Name"));coll.Add(new PropertyHeader("Price", "Price")); Once you have this collection created, you could pass this collection to a method that would create the GridViewColumn objects based on the information in this collection. Below is the full code for the PropertyHeader class. Besides the PropertyName and Header properties, there is a constructor that will allow you to set both properties when the object is created. C#public class PropertyHeader{  public PropertyHeader()  {  }   public PropertyHeader(string propertyName, string headerText)  {    PropertyName = propertyName;    HeaderText = headerText;  }   public string PropertyName { get; set; }  public string HeaderText { get; set; }} VB.NETPublic Class PropertyHeader  Public Sub New()  End Sub   Public Sub New(ByVal propName As String, ByVal header As String)    PropertyName = propName    HeaderText = header  End Sub   Private mPropertyName As String  Private mHeaderText As String   Public Property PropertyName() As String    Get      Return mPropertyName    End Get    Set(ByVal value As String)      mPropertyName = value    End Set  End Property   Public Property HeaderText() As String    Get      Return mHeaderText    End Get    Set(ByVal value As String)      mHeaderText = value    End Set  End PropertyEnd Class You can use a Generic List class to create a collection of PropertyHeader objects as shown in the following code. C#public class PropertyHeaders : List<PropertyHeader>{} VB.NETPublic Class PropertyHeaders  Inherits List(Of PropertyHeader)End Class Create Property Header Objects You need to create a method somewhere that will create and return a collection of PropertyHeader objects that will represent the columns you wish to add to your ListView prior to binding your collection class to that ListView. Below is a sample method called GetProperties that builds a list of PropertyHeader objects with properties and headers for a Product object. C#public PropertyHeaders GetProperties(){  PropertyHeaders coll = new PropertyHeaders();   coll.Add(new PropertyHeader("ProductId", "Product ID"));  coll.Add(new PropertyHeader("ProductName", "Product Name"));  coll.Add(new PropertyHeader("Price", "Price"));   return coll;} VB.NETPublic Function GetProperties() As PropertyHeaders  Dim coll As New PropertyHeaders()   coll.Add(New PropertyHeader("ProductId", "Product ID"))  coll.Add(New PropertyHeader("ProductName", "Product Name"))  coll.Add(New PropertyHeader("Price", "Price"))   Return collEnd Function WPFListViewCommon Class Now that you have a collection of PropertyHeader objects you need a method that will create a GridView and a collection of GridViewColumn objects based on this PropertyHeader collection. Below is a static/Shared method that you might put into a class called WPFListViewCommon. C#public static GridView CreateGridViewColumns(  PropertyHeaders properties){  GridView gv;  GridViewColumn gvc;   // Create the GridView  gv = new GridView();  gv.AllowsColumnReorder = true;   // Create the GridView Columns  foreach (PropertyHeader item in properties)  {    gvc = new GridViewColumn();    gvc.DisplayMemberBinding = new Binding(item.PropertyName);    gvc.Header = item.HeaderText;    gvc.Width = Double.NaN;    gv.Columns.Add(gvc);  }   return gv;} VB.NETPublic Shared Function CreateGridViewColumns( _    ByVal properties As PropertyHeaders) As GridView  Dim gv As GridView  Dim gvc As GridViewColumn   ' Create the GridView  gv = New GridView()  gv.AllowsColumnReorder = True   ' Create the GridView Columns  For Each item As PropertyHeader In properties    gvc = New GridViewColumn()    gvc.DisplayMemberBinding = New Binding(item.PropertyName)    gvc.Header = item.HeaderText    gvc.Width = [Double].NaN    gv.Columns.Add(gvc)  Next   Return gvEnd Function Build the Product Screen To build the window shown in Figure 1, you might write code like the following: C#private void CollectionSample(){  Product prod = new Product();   // Setup the GridView Columns  lstData.View = WPFListViewCommon.CreateGridViewColumns(       prod.GetProperties());  lstData.DataContext = prod.GetProducts();} VB.NETPrivate Sub CollectionSample()  Dim prod As New Product()   ' Setup the GridView Columns  lstData.View = WPFListViewCommon.CreateGridViewColumns( _       prod.GetProperties())  lstData.DataContext = prod.GetProducts()End Sub The Product class contains a method called GetProperties that returns a PropertyHeaders collection. You pass this collection to the WPFListViewCommon’s CreateGridViewColumns method and it will create a GridView for the ListView. When you then feed the DataContext property of the ListView the Product collection the appropriate columns have already been created and data bound. Summary In this blog you learned how to create a ListView that acts like a DataGrid using a collection class. While it does take a little code to do this, it is an alternative to creating each GridViewColumn in XAML. This gives you a lot of flexibility. You could even read in the property names and header text from an XML file for a truly configurable ListView. NOTE: You can download the complete sample code (in both VB and C#) at my website. http://www.pdsa.com/downloads. Choose Tips & Tricks, then "WPF ListView as a DataGrid – Part 2" from the drop-down. Good Luck with your Coding,Paul Sheriff ** SPECIAL OFFER FOR MY BLOG READERS **Visit http://www.pdsa.com/Event/Blog for a free eBook on "Fundamentals of N-Tier".  

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  • Web 2.0 Extension for ASP.NET

    - by Visual WebGui
    ASP.NET is now much extended to support line of business and data centric applications, providing Web 2.0 rich user interfaces within a native web environment. New capabilities allowed by the Visual WebGui extension turn Visual Studio into a rapid development tool for the web, leveraging the wide set of ASP.NET web infrastructures runtime and extending its paradigms to support highly interactive applications. Taking advantage of the ASP.NET infrastructures Using the native ASP.NET ISAPI filter: aspnet_isapi...(read more)

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  • Does anyone know of a good Commercial WPF Web Browser Control?

    - by VoidDweller
    I have an MDI WPF app that I need to add web content too. At first, great it looks like I have 2 options built into the framework the Frame control and the WebBrowser control. Given that this is an MDI app it doesn't take long to discover that neither of these will work. The WebBrowser control wraps up the IE WebBrowser ActiveX Control which uses the Win32 graphics pipeline. The "Airspace" issue pretty much sums this up as "Sorry, the layouts will not play nice together". Yes, I have thought about taking snapshots of the web content rendering these and mapping the mouse and keyboard events back to the browser control, but I can't afford the performance penalty and I really don't have time to write and thoroughly test it. I have looked for third party controls, but so far I have only found Chris Cavanagh's WPF Chromium Web Browser control. Which wraps up Awesomium 1.5. Together these are very cool, they play nice with the WPF layouts. But they do not meet my performance requirements. They are VERY HEAVY on memory consumption and not to friendly with CPU usage either. Not to mention still quite buggy. I'll elaborate if you are interested. So, do any of you know of a stable performant WPF web browser control? Thanks.

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  • Is there a WPF Cheat Sheet available?

    - by Pop Catalin
    I'm looking for a WPF cheat sheet that has the WPF markup extensions for binding, resources, and other common things in WPF.But so far I've had trouble finding it. Anyone know where I could find one? Thanks Edit: Thanks to John and Nir for creating two WPF cheat sheets and posting them here John's XAML for WPF CheatSheet 1.0 (Draft) Nir's WPF XAML Data Binding Cheat Sheet

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  • Sorting a ListView in WPF – Part II

    - by marianor
    Some time ago I wrote a post about how to sort a ListView by clicking on the header of the column. The problem with that solution was that you needed to implement it each time and you have to define an explicit header for each column. As a more general solution I use attached properties to extend the ListView and GridViewColumn . The first attached property is tied to the ListView itself, and it indicates that the control supports sorting. This property attach or detach to the Click event of the...(read more)

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