Archive for the ‘WPF’ Category.

How to have the TextBlock in a left column of a Grid in a ListView Template expand or shrink with text wrapping?

Ok, lets say you want to have a Grid where each item is a row of data in a Grid. The left most column should expand or shrink, and yes the text should wrap when it shrinks.

Not so easy…but it can be done if you use the right tools.

  • Use a DockPanel not a Grid
  • Make the left most column the last one added
<Window x:Class="ListBoxWithWrap.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow"
        mc:Ignorable="d" xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        d:DesignHeight="242"
        d:DesignWidth="388"
        >
    <Grid>
        <DockPanel Name="MainGrid" HorizontalAlignment="Stretch">
            <!-- These four blocks will have other content eventually, but only need to be 45 wide -->
            <TextBlock Text="X" Grid.Column="1" HorizontalAlignment="Center" Width="45" DockPanel.Dock="Right"/>
            <TextBlock Text="X" Grid.Column="2" HorizontalAlignment="Center" Width="45" DockPanel.Dock="Right"/>
            <TextBlock Text="X" Grid.Column="3" HorizontalAlignment="Center" Width="45" DockPanel.Dock="Right"/>
            <TextBlock Text="X" Grid.Column="4" HorizontalAlignment="Center" Width="45" DockPanel.Dock="Right"/>
            <!-- This is the TextBlock that needs to wrap its content (and
                             change the height of the row (so the full content is still
                             visible) to whatever the available space is, but should not
                             make overall ListView wider than the parent's width. -->
            <TextBlock Text="A very long string that should wrap when the window is small." Padding="20,6,6,6" TextWrapping="Wrap" DockPanel.Dock="Right"/>
        </DockPanel>
    </Grid>
</Window>

You will see that this works as you desire.

Now put this in a ListView’s Template and set it to use Binding.

<Window x:Class="ListBoxWithWrap.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow"
        mc:Ignorable="d"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        d:DesignHeight="242"
        d:DesignWidth="388"
        SizeToContent="WidthAndHeight">
    <Grid>
        <ListView Name="lvWrap" ItemsSource="{Binding}">
            <ListView.ItemTemplate>
                <DataTemplate>
                    <DockPanel Name="MainGrid" HorizontalAlignment="Stretch">
                        <!-- These four blocks will have other content eventually, but only need to be 45 wide -->
                        <TextBlock Text="X" Grid.Column="1" HorizontalAlignment="Center" Width="45" DockPanel.Dock="Right"/>
                        <TextBlock Text="X" Grid.Column="2" HorizontalAlignment="Center" Width="45" DockPanel.Dock="Right"/>
                        <TextBlock Text="X" Grid.Column="3" HorizontalAlignment="Center" Width="45" DockPanel.Dock="Right"/>
                        <TextBlock Text="X" Grid.Column="4" HorizontalAlignment="Center" Width="45" DockPanel.Dock="Right"/>
                        <!-- This is the TextBlock that needs to wrap its content (and
                             change the height of the row (so the full content is still
                             visible) to whatever the available space is, but should not
                             make overall ListView wider than the parent's width. -->
                        <TextBlock Text="{Binding Content}" Padding="20,6,6,6" TextWrapping="Wrap" DockPanel.Dock="Right"/>
                    </DockPanel>
                </DataTemplate>
            </ListView.ItemTemplate>
        </ListView>
    </Grid>
</Window>

Now give it some data to bind to.

using System.Collections.Generic;
using System.Windows;
using System.Windows.Documents;

namespace ListBoxWithWrap
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();

            List<SomeItem> list = new List<SomeItem>();
            list.Add(new SomeItem() { Content = "Some very long string with so many words there should be some wrapping going on to prevent a line of text that is too long" });
            list.Add(new SomeItem() { Content = "Some very long string with so many words there should be some wrapping going on to prevent a line of text that is too long" });
            list.Add(new SomeItem() { Content = "Some very long string with so many words there should be some wrapping going on to prevent a line of text that is too long" });
            list.Add(new SomeItem() { Content = "Some very long string with so many words there should be some wrapping going on to prevent a line of text that is too long" });
            list.Add(new SomeItem() { Content = "Some very long string with so many words there should be some wrapping going on to prevent a line of text that is too long" });

            lvWrap.DataContext = list;
        }

        public class SomeItem
        {
            public string Content { get; set; }
        }
    }
}

The shrink with text wrapping no longer works once inside of the ListView. So that tells you that something to do with the ListView is breaking the feature you want.

Here is how you fix this:

1. Open your project in Expression Blend. (If you don’t have Expression Blend, maybe just look at my code below and copy it)

2. Right-Click on the ListView in the Object and Timeline tab and choose Edit Template | Edit a Copy.

3. Click OK on the next Window.

This will create the following resource code.

<Window.Resources>
		<SolidColorBrush x:Key="ListBorder" Color="#828790"/>
		<Style x:Key="ListViewStyle1" TargetType="{x:Type ListView}">
			<Setter Property="Background" Value="{DynamicResource {x:Static SystemColors.WindowBrushKey}}"/>
			<Setter Property="BorderBrush" Value="{StaticResource ListBorder}"/>
			<Setter Property="BorderThickness" Value="1"/>
			<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
			<Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto"/>
			<Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto"/>
			<Setter Property="ScrollViewer.CanContentScroll" Value="true"/>
			<Setter Property="ScrollViewer.PanningMode" Value="Both"/>
			<Setter Property="Stylus.IsFlicksEnabled" Value="False"/>
			<Setter Property="VerticalContentAlignment" Value="Center"/>
			<Setter Property="Template">
				<Setter.Value>
					<ControlTemplate TargetType="{x:Type ListView}">
						<Border x:Name="Bd" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Padding="1" SnapsToDevicePixels="true">
							<ScrollViewer Focusable="false" Padding="{TemplateBinding Padding}">
								<ItemsPresenter SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
							</ScrollViewer>
						</Border>
						<ControlTemplate.Triggers>
							<Trigger Property="IsEnabled" Value="false">
								<Setter Property="Background" TargetName="Bd" Value="{DynamicResource {x:Static SystemColors.ControlBrushKey}}"/>
							</Trigger>
							<Trigger Property="IsGrouping" Value="true">
								<Setter Property="ScrollViewer.CanContentScroll" Value="false"/>
							</Trigger>
						</ControlTemplate.Triggers>
					</ControlTemplate>
				</Setter.Value>
			</Setter>
		</Style>
	</Window.Resources>

4. Now look at what is surrounding the ItemPresenter. Yes, you see the ScrollViewer, which is your problem. Delete it.

5. Build you project.

Success! Now your feature to both expand or shrink with text wrapping is back.

Here is the final XAML.

<Window x:Class="ListBoxWithWrap.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow"
        mc:Ignorable="d"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        d:DesignHeight="242"
        d:DesignWidth="388"
        SizeToContent="WidthAndHeight">
    <Window.Resources>
        <SolidColorBrush x:Key="ListBorder" Color="#828790"/>
        <Style x:Key="ListViewStyle1" TargetType="{x:Type ListView}">
            <Setter Property="Background" Value="{DynamicResource {x:Static SystemColors.WindowBrushKey}}"/>
            <Setter Property="BorderBrush" Value="{StaticResource ListBorder}"/>
            <Setter Property="BorderThickness" Value="1"/>
            <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
            <Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto"/>
            <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto"/>
            <Setter Property="ScrollViewer.CanContentScroll" Value="true"/>
            <Setter Property="ScrollViewer.PanningMode" Value="Both"/>
            <Setter Property="Stylus.IsFlicksEnabled" Value="False"/>
            <Setter Property="VerticalContentAlignment" Value="Center"/>
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="{x:Type ListView}">
                        <Border x:Name="Bd" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Padding="1" SnapsToDevicePixels="true">
                            <ItemsPresenter SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
                        </Border>
                        <ControlTemplate.Triggers>
                            <Trigger Property="IsEnabled" Value="false">
                                <Setter Property="Background" TargetName="Bd" Value="{DynamicResource {x:Static SystemColors.ControlBrushKey}}"/>
                            </Trigger>
                            <Trigger Property="IsGrouping" Value="true">
                                <Setter Property="ScrollViewer.CanContentScroll" Value="false"/>
                            </Trigger>
                        </ControlTemplate.Triggers>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
    </Window.Resources>
    <Grid>
        <ListView Name="lvWrap" ItemsSource="{Binding}" Style="{DynamicResource ListViewStyle1}">
            <ListView.ItemTemplate>
                <DataTemplate>
                    <DockPanel Name="MainGrid" HorizontalAlignment="Stretch">
                        <!-- These four blocks will have other content eventually, but only need to be 45 wide -->
                        <TextBlock Text="X" Grid.Column="1" HorizontalAlignment="Center" Width="45" DockPanel.Dock="Right"/>
                        <TextBlock Text="X" Grid.Column="2" HorizontalAlignment="Center" Width="45" DockPanel.Dock="Right"/>
                        <TextBlock Text="X" Grid.Column="3" HorizontalAlignment="Center" Width="45" DockPanel.Dock="Right"/>
                        <TextBlock Text="X" Grid.Column="4" HorizontalAlignment="Center" Width="45" DockPanel.Dock="Right"/>
                        <!-- This is the TextBlock that needs to wrap its content (and
                             change the height of the row (so the full content is still
                             visible) to whatever the available space is, but should not
                             make overall ListView wider than the parent's width. -->
                        <TextBlock Text="{Binding Content}" Padding="20,6,6,6" TextWrapping="Wrap" DockPanel.Dock="Right"/>
                    </DockPanel>
                </DataTemplate>
            </ListView.ItemTemplate>
        </ListView>
    </Grid>
</Window>

You should now have a little bit more understanding of the ListView template and how to manipulate it, which should translate to other objects in WPF as well.

A quick overview of MVVM

Model View ViewModel (MVVM) is a design pattern based on Model View Controller (MVC) but specifically tailored to Windows Presentation Foundation (WPF).

MVVM is not a framework per se but many frameworks have been created. Here is a list of MVVM Frameworks from Wikipedia.

See the Wikipedia site here: Open Source MVVM Frameworks.

Another blog, has some basic information on many of these here: A quick tour of existing MVVM frameworks

A framework is actually not necessary to implement MVVM and you should seriously consider whether using one is right for your WPF application or not. Many applications do not need much of the features the frameworks provide. However, there are two common classes that all MVVM frameworks contain. These are ViewModelBase and RelayCommand. Though some frameworks may give them different names or implement them slightly differently, they all have these classes. For example, MVVM Foundation names the ViewModelBase differently. It is called ObservableObject, which is more appropriate because it is incorrect to assume that all objects that implement INotifyPropertyChanged are going to be ViewModel objects.

Instead of installing and using an MVVM framework, you could simply include these classes in your application, as these are all you need to implement MVVM.

  • ObservableObject
  • RelayCommand

While these two classes are enough, you may want to investigate how different MVVM Frameworks implement and what else they implement and why. You may find that another feature implemented is exactly what you need in your application and knowing about it could save you time.

A WPF front-end for LDPing

I wrote a front-end to LDPing last week-end. You can check it out here:

LDPing

So I was writing a WPF front-end for LDPing, which is a method of querying a LANDesk Agent for its computer name and Inventory Id. There is a button that you click to launch the ping and I couldn’t get the thing to enable…Anyway, I figured it out and posted the resolution here:

Refreshing a button enabled/disabled by RelayCommand.CanExecute()

So here is a screen shot of LDPing.

How to disable row selection in a WPF DataGrid?

Disabling row selection in the WPF DataGrid included in .NET Framework 4 is not really easy. It is extremely difficult to do, unless you have the right tools and know exactly how to do it.

But all the difficulty is in figuring out how to do it. Once you know how to do it, the steps are quite easy to perform.

First, you basically have to use a copy of the default DataGrid style. However, the easiest way to get a copy of the default DataGrid style is using Expression Blend.

Read more one my new WPF Sharp site here:

How to disable row selection in a WPF DataGrid?

How to create a copy of a control’s default style?

Sometimes you need to make some advanced styling changes to a default control, such as a RadioButton, ListBox, DataGrid, Button, etc. However, you may want to keep the majority of the default style the way it is.

In Expression Blend, this is easy to do. If you don’t have Expression Blend and you are developing in WPF, get it immediately. There is a trial version you can test out.

Here is how to get your copy of any control’s default style….

Read more on my new WPF Sharp site
How to create a copy of a control’s default style?

10 Step process for developing a new WPF application the right way using C#

It makes a difference if you do something the right way from the beginning.  Everything seems to work out so much better and takes less time over all.

Here are some basic steps that I have learned will help you do it right the first time. These steps are from my experience, mostly because I did it wrong the first few times.  These are not exact steps. They are subject to change and improve.  In fact, you might have improvements to suggest immediately when you read this. But if you are new to WPF, then reading these steps before you start and following them, will have you closer it doing it the right way the first time.  It is much more pleasant to tweak a pretty good process than it is to go in with no idea for a process and do it wrong.

Step 1 – Prepare the idea

  1. Some one has an idea
  2. Determine the minimal features for release 1.
  3. Determine the minimal features for release 2.
    1. Alter minimal features for release 1 if it makes sense to do so.
  4. Determine the minimal features for release 3.
    1. Alter minimal features for release 1 and 2 if it makes sense to do so.

Step 2 – Design the Application’s back end business logic (simultaneous to Step 3)

  1. Design the backend
  2. Apply the “Keep it simple” idea to the business logic and makes changes as necessary.
  3. Apply the “Keep it secure” idea to the business logic and makes changes as necessary.
  4. Repeats steps 2 and 3 if necessary.
  5. Backend development can start now as the UI and the back end should not need to know about each other, though this coding is listed as the Step 5 item.

Step 3 – Design the UI using WPF (simultaneous to Step 2)

  1. Determine what development model should be used to separate the UI from the business logic.
    1. Model-View-ViewModel (MVVM) is the model I recommend for WPF.
    2. Gather libraries used for the model (such as common MVVM libraries that include the common ViewModelBase and RelayCommand objects)
  2. Consider using a 3rd party WPF control set will be used.  Many 3rd party companies provide WPF controls that are better and easier to use than those included by default.
    1. If you decided to use 3rd party controls, purchase or otherwise obtain the libraries for these 3rd party controls.
  3. Consider designing two WPF interfaces or skins (I will call these Views from here on out) for each screen. This will help drive the separation of the back end code from the WPF code. Also if developing two Views is not simple, it indicates a poor design.
  4. Design the interface(s) (you may be doing two Views) using SketchFlow (take time to include the libraries for the 3rd party WPF Controls in your SketchFlow project and design with them)
    1. SketchFlow allows you to design the UI, which is commonly done in paint, but instead does this in XAML, and is actually the WPF code your application will use.
  5. SketchFlow allows you to deliver the design (or both Views if you did two) as a package to the customer.
    1. Deliver it immediately and get feedback.
    2. Make changes suggested by the customer if in scope.
  6. Take time to make the XAML in SketchFlow production ready.
  7. Deliver the XAML to the customer again, to buy of that the design changes are proper.
    1. Make changes suggested by the customer if in scope.

Step 4 – Determine the delivery or install method

  1. Determine the delivery method.
  2. Determine when to develop the delivery method.
    1. The easier the application is, the longer you can wait to determine the installer or delivery method.
    2. The more complex the install or delivery method, the sooner this should be started.

Step 5 – Develop the business logic

  1. Develop the application designed in step 2.
  2. Get the application working without UI or silently. Note: Start the next step, Develop the UI, as soon as enough code is available here.

Step 6 – Add Bindings to the UI

  1. Start the UI project by copying the XAML from the SketchFlow document to your Visual Studio or Expression Blend project.
  2. Determine a method for setting the DataContext without linking the View to any ViewModel or Model dlls.
  3. Create a project for the ViewModel code and develop it to interact with the business logic using Binding.
  4. Remember to develop two Views for every UI screen as this will help, though not guarantee, that the the MVVM model was correctly used.

Step 7 – Develop the View Model

  1. You should now have a backend code and a View, and now you start creating the View Model.
  2. This should be in a separate dll than the View or ViewModel.
  3. The ViewModel should never link to the View but can link to Model and Business libraries, though you may consider interface-based design and only link to an interface library.
  4. Make sure to use the properties that the View is binding to.

Step 8 – Consider a other platforms

Macintosh

Macintosh owns a significant market share.  Determine if this application needs to run on Macintosh as well. Sure, since we are running C# your options are limited to either rewriting in objective C and Coca, or using Mono with a MonoMac UI.  I recommend the latter.

Note: It is critical that the UI and business logic are separated to really make this successful.

  1. Completely ignore the WPF design and have Macintosh users users assist the design team in designing the new UI.  Macintosh’s have a different feel, and trying to convert the same UI is a mistake.
  2. Create the MonoMac UI project.
  3. Create a project similar to the ViewModel project in Windows, to link the UI to the business logic.

BSD/Linux/Unix

BLU (BSD/Linux/Unix) doesn’t exactly own a significant market share. However, it is still important to determine if this application needs to run on on BLU as well. Sure, since we are running C# your options are limited to either rewriting in C++, or using Mono with a GTK# or Forms UI.

  1. Completely ignore the WPF and Macintosh designs and have Linux users assist the design team in designing the new UI. Linux have a different feel, and trying to convert the same UI is a mistake.
  2. Create the GTK# project.
  3. Create a project similar to the ViewModel project in Windows, to link the UI to the business logic.
  4. GTK# doesn’t support binding, but still keep the UI separate from the business logic as much as possible.
  5. Also, don’t develop for a single open source flavor, but use standard code that compiles and any BSD/Linux/Unix platform.

Mobile Platforms

  1. Do you need to have this app on IOS or Android or Windows Phone?
  2. Completely ignore the WPF and Macintosh and Linux designs and have Android or IOS users assist the design team in designing the new UI. Mobile platforms have a different feel, and trying to convert the same UI is impossible as the screens are much smaller.

Step 9 – Develop the delivery method

Again, you may need to do this way sooner if the application is complex.

  1. Develop the install or delivery method.
  2. If you decided to deploy to Macintosh or BLU you may have to develop separate install or delivery methods for those platforms as well.
  3. Remember to have a plan and a test for your first patch even if you have to mock a sample patch before you release.
  4. Remember to have a plan and a test for upgrading your application even if you have to mock a sample upgrade version before you release.

Step 10 – Deliver the finished Products

  1. Once finished, deliver this product.
  2. If you decided to create a Macintosh or BLU version, deliver them when ready as well.  It is OK and maybe preferred to deliver these at different times.

How to configure the WPF RadioButton’s circle bullet top aligned when there are multiple lines of text?

Today I had to solve a problem that appeared quite difficult, but turned out to not be so hard if I let Expression Blend do most the work and finish it up in the XAML. I ended up having to completely recreate the default template style and then modify it.

Note: This article could also be titled: How to change the default template style of a standard control?

I had a RadioButton with text that wraps and it wasn’t displaying exactly how my team wanted. Here is the XAML.

<Window x:Class="RadioButtonTopAligned.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <RadioButton GroupName="RadioButtonList">
            <Label>
                <AccessText TextWrapping="Wrap" Text="_This is a very long radio button control line of text that should wrap." MaxWidth="300"/>
            </Label>
        </RadioButton>
    </Grid>
</Window>

The problem is that the circle bullet is center aligned like this:

Notice how the circle bullet is aligned in between the two lines of text. I need it to be top aligned like this:

Notice how the circle bullet is aligned with the top line of text. I need to get WPF to do this.

From a Visual Studio 2010 point of view, there is no easy way to do this. At first I thought it would be a simple dependency property, but it isn’t. An quick internet search led me to realize that I have to pretty much re-style the whole RadioButton. This sounds really hard and in fact, in Visual Studio, without help, it would be really hard. You would have to have the code for the default template style for the RadioButton control memorized.

Here is an forum post I found from MSDN: How do I make a RadioButton’s Bullet align top

While the post is exactly what I was looking for and has an answer, I didn’t at first grasp the answer. I wasn’t sure what was going on until one of my co-workers, Shawn, who is more skilled in Expression Blend, showed me. Now that I understand, I want to make sure the next person who finds the same forum post on MSDN can understand even easier by writing this article and adding it to the forum post.

This is where Expression Blend comes in. If you don’t have Expression Blend, don’t worry, you can still get through this article as I will include the the default style code that Expression Blend created for me right here in my post.

In Expression Blend, this is what to do.

  1. Create a blank WPF project in Expression Blend.
  2. Add a RadioButton.
  3. Right-click on the RadioButton and choose Edit Template | Edit a Copy…
  4. Click OK on the Create Style Resource window.

Here is what happens to your XAML and you can do this to the XAML in you project manually if you don’t have Expression Blend.

  1. The following reference is added to the project: PresentationFramework.Aero
  2. The same is referenced in the XAML (See line 4 of the XAML below)
  3. The default RadioButton style is copied to your XAML under the Window.Resources element.  (See lines 10-48 in the XAML below)
  4. The RadioButton is assigned the style created. (See line 51 in the XAML below)
<Window
	xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
	xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
	xmlns:Microsoft_Windows_Themes="clr-namespace:Microsoft.Windows.Themes;assembly=PresentationFramework.Aero"
	x:Class="RadioButtonTopAligned_EB.MainWindow"
	x:Name="Window"
	Title="MainWindow"
	Width="640" Height="480">

	<Window.Resources>
		<SolidColorBrush x:Key="CheckBoxStroke" Color="#8E8F8F"/>
		<Style x:Key="CheckRadioFocusVisual">
			<Setter Property="Control.Template">
				<Setter.Value>
					<ControlTemplate>
						<Rectangle Margin="14,0,0,0" SnapsToDevicePixels="true" Stroke="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}" StrokeThickness="1" StrokeDashArray="1 2"/>
					</ControlTemplate>
				</Setter.Value>
			</Setter>
		</Style>
		<Style x:Key="RadioButtonStyle1" TargetType="{x:Type RadioButton}">
			<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
			<Setter Property="Background" Value="#F4F4F4"/>
			<Setter Property="BorderBrush" Value="{StaticResource CheckBoxStroke}"/>
			<Setter Property="BorderThickness" Value="1"/>
			<Setter Property="Template">
				<Setter.Value>
					<ControlTemplate TargetType="{x:Type RadioButton}">
						<BulletDecorator Background="Transparent">
							<BulletDecorator.Bullet>
								<Microsoft_Windows_Themes:BulletChrome BorderBrush="{TemplateBinding BorderBrush}" Background="{TemplateBinding Background}" IsChecked="{TemplateBinding IsChecked}" IsRound="true" RenderMouseOver="{TemplateBinding IsMouseOver}" RenderPressed="{TemplateBinding IsPressed}"/>
							</BulletDecorator.Bullet>
							<ContentPresenter HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
						</BulletDecorator>
						<ControlTemplate.Triggers>
							<Trigger Property="HasContent" Value="true">
								<Setter Property="FocusVisualStyle" Value="{StaticResource CheckRadioFocusVisual}"/>
								<Setter Property="Padding" Value="4,0,0,0"/>
							</Trigger>
							<Trigger Property="IsEnabled" Value="false">
								<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}"/>
							</Trigger>
						</ControlTemplate.Triggers>
					</ControlTemplate>
				</Setter.Value>
			</Setter>
		</Style>
	</Window.Resources>

	<Grid x:Name="LayoutRoot">
		<RadioButton GroupName="RadioButtonList" Style="{DynamicResource RadioButtonStyle1}">
			<Label>
				<AccessText TextWrapping="Wrap" Text="_This is a very long radio button control line of text that should wrap." MaxWidth="300"/>
			</Label>
		</RadioButton>
	</Grid>
</Window>

Now we can edit the XAML. Below is the same XAML as above with the following edits:

  1. Inside the BulletDecorator.Bullet element on line 30, create a DockPanel around the BulletChrome element.
  2. The ControlPresenter is moved to be inside the DockPanel.
  3. Add the following XAML atrributes to the BulletChrome element:
    VerticalAlignment=”Top” Margin=”0,8,0,0″ Height=”{TemplateBinding FontSize}” Width=”{TemplateBinding FontSize}”

    Note: If you change the font of the text content in the RadioButton, you should change the Margin in the style as well. I haven’t figured out how to make it always match the top line without manually tweaking it when you change the font. Also, if you don’t want the BulletChrome element to be the same size as the font, you will have to tweak Width and Height too.

<Window
	xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
	xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
	xmlns:Microsoft_Windows_Themes="clr-namespace:Microsoft.Windows.Themes;assembly=PresentationFramework.Aero"
	x:Class="RadioButtonTopAligned_EB.MainWindow"
	x:Name="Window"
	Title="MainWindow"
	Width="640" Height="480">

	<Window.Resources>
		<SolidColorBrush x:Key="CheckBoxStroke" Color="#8E8F8F"/>
		<Style x:Key="CheckRadioFocusVisual">
			<Setter Property="Control.Template">
				<Setter.Value>
					<ControlTemplate>
						<Rectangle Margin="14,0,0,0" SnapsToDevicePixels="true" Stroke="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}" StrokeThickness="1" StrokeDashArray="1 2"/>
					</ControlTemplate>
				</Setter.Value>
			</Setter>
		</Style>
		<Style x:Key="RadioButtonStyle1" TargetType="{x:Type RadioButton}">
			<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
			<Setter Property="Background" Value="#F4F4F4"/>
			<Setter Property="BorderBrush" Value="{StaticResource CheckBoxStroke}"/>
			<Setter Property="BorderThickness" Value="1"/>
			<Setter Property="Template">
				<Setter.Value>
					<ControlTemplate TargetType="{x:Type RadioButton}">
						<BulletDecorator Background="Transparent">
							<BulletDecorator.Bullet>
								<DockPanel>
									<Microsoft_Windows_Themes:BulletChrome VerticalAlignment="Top" Margin="0,8,0,0" Height="{TemplateBinding FontSize}" Width="{TemplateBinding FontSize}" BorderBrush="{TemplateBinding BorderBrush}" Background="{TemplateBinding Background}" IsChecked="{TemplateBinding IsChecked}" IsRound="true" RenderMouseOver="{TemplateBinding IsMouseOver}" RenderPressed="{TemplateBinding IsPressed}" />
									<ContentPresenter RecognizesAccessKey="True" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
								</DockPanel>
							</BulletDecorator.Bullet>
							</BulletDecorator>
						<ControlTemplate.Triggers>
							<Trigger Property="HasContent" Value="true">
								<Setter Property="FocusVisualStyle" Value="{StaticResource CheckRadioFocusVisual}"/>
								<Setter Property="Padding" Value="4,0,0,0"/>
							</Trigger>
							<Trigger Property="IsEnabled" Value="false">
								<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}"/>
							</Trigger>
						</ControlTemplate.Triggers>
					</ControlTemplate>
				</Setter.Value>
			</Setter>
		</Style>
	</Window.Resources>

	<Grid x:Name="LayoutRoot">
		<RadioButton GroupName="RadioButtonList" Style="{DynamicResource RadioButtonStyle1}">
			<Label>
				<AccessText TextWrapping="Wrap" Text="_This is a very long radio button control line of text that should wrap." MaxWidth="300"/>
			</Label>
		</RadioButton>
	</Grid>
</Window>

I hope this posts clarifies how to completely recreate a template style for a default control to modify something that at first doesn’t appear modifiable.

WPF NavigationService blanks PasswordBox.Password, which breaks the MVVM PasswordHelper

I am using three things that are just not friends:

  • Pages and NavigationService
  • Model-View-ViewModel design
  • The PasswordBox control

Problem 1 – PasswordBox.Password is not a DependencyProperty

First off, Model-View-ViewModel is design centered around data binding. But PasswordBox.Password is not a DependencyProperty and therefore does not support binding. That is ok, a PasswordBoxAssistant (alternately I have seen it named PasswordHelper or PasswordBoxHelper) as described originally here and also here fixes seems to fix this.

That is, it fixes it unless you are using the NavigationService.

Problem 2 – NavigationService blanks PasswordBox.Password

See when the NavigationService navigates to another page, it somehow know that the current page has a PasswordBox and if it finds a PasswordBox, it blanks the password out.  So since we are using PasswordBoxHelper to make MVVM and data binding work, the value is blanked in the ViewModel and Model as well.

For now, I happen to be using a custom button for navigation so I can simply do this in my ViewModel:

String tempPw = MyPassword;
NavigationService.Navigate(NewPage);
MyPassword = tempPw;

However, this is not the best solution. What if there were multiple links and different ways to navigate?

I think the best solution would be to figure out how to make PasswordBoxAssistant handle this. But I am not sure how or if there is anyway to tell that the password was blanked by the NavigationService and to ignore binding in this instance.

Resource:

http://social.msdn.microsoft.com/Forums/en/wpf/thread/d91aec90-1476-41c0-a925-7661745094c5

Navigation and Pages using Model-View-ViewModel (MVVM)

I am working on a project at work that is a navigation application.

I wanted to use MVVM. I also wanted to document for others how I designed this, as there wasn’t much online about using MVVM with Navigation and Pages.

Here is my project. I will post an explanation of this project as soon as I can get to it, so look for it.

Project Download – Small: Navigation-Pages-MVVM.zip

Project Download – More complete: Navigation-Pages-MVVM 2.0

Expression + Sketch Flow for prototyping

I have historically done mock-ups in two ways:

  1. Just code it up
  2. Paint.NET

Neither are really good solutions.  But as a developer for an enterprise product, the above tools just are not sufficient.

So I have recently introduced to SketchFlow. This is a tool for quickly mocking up your UI.  It has some features that are quite nice and I am impressed.  I can create a UI very quickly and maybe even faster than I could with Paint.NET on the first try.  After using SketchFlow for a while, it will be a lot faster.

There are three features that make SketchFlow an amazing tool for UI prototyping.

  1. The ability to map and design at the same time
  2. The ability to package it for a demo
  3. The ability to export the prototype to word.

These features make it so that for the same or less work that we have to do anyway to provide sample screens, we also get 1) a Map that we otherwise would have had to spend extra time creating in Visio or elsewhere, 2) A packaged demo that we can send to customers for feed back early on before development so we develop it right the first time, and 3) Stub documentation with all the screens and topical guides exported to word in seconds.

All three of these features are demonstrated in this Video.

Get Microsoft Silverlight

Note: For my FreeBSD readers...this might not be for you though it would be interesting to see if Moonlight can load this video.