Develop Reference

WPF: How to access element in ResourceDictionary code behind

In my application I have a control which renders a number of blocks on a timeline view (like a calendar). One can provide a template for the blocks by giving the timeline an appropriate DataTemplate.
I would like to separate the block DataTemplate from the main timeline view, putting the block into its own XAML. As such, I've created a XAML for the Block (called Block.xaml) and wrapped the DataTemplate inside a ResourceDictionary, inside this XAML.
I've added a code behind to the XAML (called Block.xaml.cs) in which I need to access some of the elements in the block. The issue is that ResourceDictionaries seem to hide the elements from the codebehind such that I can't access them. I can't use a UserControl instead - this seems to not work.
How can I access the elements of the Block DataTemplate from the code behind?
Many thanks in advance for your help.
Block.xaml:
<ResourceDictionary x:Class="Project.Windows.MainInterface.TimelinePanel.Block" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:local="clr-namespace:Project.Windows.MainInterface.TimelinePanel" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d" xmlns:converters="clr-namespace:Project.Converters" >
<DataTemplate x:Key="ItemBlockTemplate">
<Grid Name="BlockParent" Width="Auto" Height="Auto" MinHeight="50" ClipToBounds="True" SizeChanged="BlockParent_OnSizeChanged">
<Border Panel.ZIndex="3" BorderBrush="{DynamicResource BackgroundGreyLight}" BorderThickness="1" CornerRadius="1" />
<Grid Margin="1" Background="{DynamicResource BlockBackgroundGradient}" d:LayoutOverrides="Width">
<TextBlock x:Name="blockName" Height="20" Margin="4,0,4,0" Padding="3" VerticalAlignment="Top" Panel.ZIndex="3" FontSize="10" Foreground="{DynamicResource TextLight}" Text="{Binding blockName}" TextTrimming="CharacterEllipsis" Visibility="Visible" />
<TextBlock x:Name="Duration" Margin="0,2,4,2" Padding="0,0,3,0" HorizontalAlignment="Right" VerticalAlignment="Bottom" Panel.ZIndex="5" FontSize="10" Foreground="{DynamicResource TextLight}" Text="{Binding FormattedDuration}" ToolTip="{Binding Duration}" />
<Grid Background="#FF0FA8FF" Opacity="0.7" />
</Grid>
</Grid>
</DataTemplate>
Snippet of the Timeline in the main interface:
...
<timeLineTool:TimeLineControl x:Name="Timeline" Height="50" MinWidth="50" Margin="0,0,12,0" HorizontalAlignment="Left" VerticalAlignment="Top" Items="{Binding Timeline}" SnapsToDevicePixels="True" UnitSize="{Binding UnitSize}" UseLayoutRounding="True">
<timeLineTool:TimeLineControl.ItemTemplate>
<DataTemplate DataType="{x:Type local:BlockItemViewModel}">
<ContentControl>
<ContentPresenter Margin="0" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Content="{Binding}" ContentTemplate="{StaticResource ItemBlockTemplate}" />
</ContentControl>
</DataTemplate>
</timeLineTool:TimeLineControl.ItemTemplate>
</timeLineTool:TimeLineControl>
...
...If I could use a UserControl instead of a ResourceDictionary for my Block, this would solve the problem, as all elements are automatically publicly available in the code behind for usercontrols.

Sample XAML:
<Window.Resources>
<ControlTemplate x:Key="ResourceName" TargetType="{x:Type Label}">
<Label Foreground="White" Content="{iconPacks:PackIconFontAwesome plug,Height=40,Width=40}"/>
</ControlTemplate>
</Window.Resources>
Code behind
ControlTemplate Dictionary:
private Dictionary<string, ControlTemplate> collection
{
get
{
Dictionary<string, ControlTemplate> controlTemplates = new Dictionary<string, ControlTemplate>();
controlTemplates.Add("ResourceName", FindResource("ResourceName") as ControlTemplate);
return controlTemplates;
}
}
Use ControlTemplate:
Label LBDisConnect = new Label();
LBDisConnect.Template = collection["ResourceName"];
LoginInfo.Children.Add(LBDisConnect);

Multiple usercontrol not reflected while setting DataTemplate to ViewModel in MVVM

I am trying to add two usercontrols in one view
usercontrol working fine which get call in constructor i am implementing INotifyPropertyChanged for 'SelectedViewModel'.
property get updated for second usercontrol but not reflected in view .
thanks in advance
<Window x:Class="MovieBookinGWithUserControl.View.StartupWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:MovieBookinGWithUserControl.ViewModel"
xmlns:localview ="clr-namespace:MovieBookinGWithUserControl.View"
Title="StartupWindow" Height="AUTo" Width="Auto">
<Window.Resources>
<DataTemplate DataType="{x:Type local:LoginWIndowViewModel}">
<localview:LoginWindow></localview:LoginWindow>
</DataTemplate>
<DataTemplate DataType="{x:Type local:MovieInfoViewModel }">
<localview:MovieInfo ></localview:MovieInfo>
</DataTemplate>
</Window.Resources>
<Grid>
<DockPanel LastChildFill="True">
<StackPanel x:Name="navigation" DockPanel.Dock="Left" Width="Auto">
</StackPanel>
<ContentControl x:Name="Pages" DockPanel.Dock="Right" Content="{Binding SelectedViewModel,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"/>
</DockPanel>
</Grid>
</Window>

WPF Expander overlay used in ItemsControl

I've been searching for some time but all solution I find only tackle parts of my issue.
I'd like to have an ItemsControl with each item containing an Expander. On expanding, the Expander's content should be shown as an overlay overlapping the other items in the ItemsControl and not moving them down.
The following XAML-Code does exactly as supposed to with one big issue: The Expander's content does not overlap the other items but is hidden behind them. I suppose this is due to the ZIndex as the following items in the ItemsControl are added after the Expander's content.
I managed to set one single Expander's ZIndex to 99 using style triggers but this seems to be a too complicated and error-prone solution. Any thoughts?
<Window x:Class="WpfTest.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">
<Window.Resources>
<x:Array x:Key="items"
Type="sys:String"
xmlns:sys="clr-namespace:System;assembly=mscorlib">
<sys:String>One</sys:String>
<sys:String>Two</sys:String>
<sys:String>Three</sys:String>
<sys:String>Four</sys:String>
</x:Array>
<DataTemplate x:Key="template">
<Grid Background="Red" Margin="0,0,0,10">
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<TextBlock Text="{Binding}" />
<Canvas Height="25" Grid.Row="1">
<Expander ExpandDirection="Down" Header="Header" Grid.Row="1">
<Expander.Content>
<TextBlock Height="80" Text="Content" Background="Yellow" />
</Expander.Content>
</Expander>
</Canvas>
</Grid>
</DataTemplate>
</Window.Resources>
<Grid>
<ScrollViewer>
<ItemsControl ItemsSource="{StaticResource items}"
ItemTemplate="{StaticResource template}"
HorizontalContentAlignment="Stretch">
</ItemsControl>
</ScrollViewer>
</Grid>
</Window>

It's going to be tricky to achieve this in the way you are attempting it. The problem is the nested structure -- since each Canvas is nested inside a Grid, you won't be able to control its z-index relative to other Canvas element. To illustrate this, here is a schematic of the visual tree created by your current markup:
<StackPanel> <!-- items panel -->
<ContentPresenter> <!-- item wrapper -->
<Grid>
<Canvas>
</Canvas>
</Grid>
</ContentPresenter>
<ContentPresenter> <!-- item wrapper -->
<Grid>
<Canvas>
</Canvas>
</Grid>
</ContentPresenter>
</StackPanel>
With reference to the above, your goal will be to have the Canvas elements appear in front of the siblings of its parent ContentPresenter. This is impossible in this hierarchy, because ZIndex only applies relative to siblings of the same parent element. Now, there might be ways you could massage the above into a flat structure so that you could then apply ZIndex your expanded content as needed.
However, I think an easier and more natural approach would be to use Popup elements for the expanded content. A Popup is a framework primitive that is located outside of the visual tree, and will always sit on top of your other content. You can use a ToggleButton or something similar to create the "expand" effect. For example:
<StackPanel Grid.Row="1">
<ToggleButton x:Name="PopupToggle" Content="Expand" />
<Popup IsOpen="{Binding IsChecked,ElementName=PopupToggle}">
<TextBlock Height="80" Text="Content" Background="Yellow" />
</Popup>
</StackPanel>

Updating data binding source of a content control in a ResourceDictionary

I want to create a view that has a set of tabs (each, basically a ContentControl) that each have various settings. I then want to have a button that will update all of the data binding rather than updating instantly or having update buttons associated with the controls themselves
So, my control is MEF exported as a ResourceDictionary and is similar to the below
<ResourceDictionary ...>
<DataTemplate DataType="{x:Type vm:AdminViewModel}">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="*"/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<TabControl Grid.Row="0">
<TabItem Header="Tests">
<ContentControl Content="{Binding ResultStorage}"/>
</TabItem>
</TabControl>
<StackPanel Grid.Row="1" Orientation="Horizontal">
<Button Content="Update"/>
<Button Content="Cancel"/>
</StackPanel>
</Grid>
</DataTemplate>
</ResourceDictionary>
TestStorage would be like this:
<ResourceDictionary ...>
<DataTemplate DataType="{x:Type data:XmlResultStorage}">
<StackPanel>
<TextBlock Text="Result File Path:"/>
<TextBox Text="{Binding Path=ResultPath, Source={x:Static properties:DataStorage.Default}, UpdateSourceTrigger=Explicit}"/>
<TextBlock Text="Result File Location:"/>
<TextBox Text="{Binding Path=ResultFilename, Source={x:Static properties:DataStorage.Default}, UpdateSourceTrigger=Explicit}"/>
</StackPanel>
</DataTemplate>
What I want to do is when the button to update is pressed to somehow call the update (UpdateSource?) on the ContentControl but I can't see how to do it.
In an ideal world I wouldn't have code-behind and do it all via MVVM or something, but if that's not possible code-behind is fine.
So I have two issues, how do I update data bindings manually via a ResourceDictionary and how do I then cause it to cascade through its child ContentControls?

Caliburn Micro: UserControl Binding

I use Caliburn Micro for my WPF application. I implemented a little UserControl:
<UserControl Name="ImageButtonUserControl"
x:Class="SportyMate.Utility.Controls.ImageButton"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006">
<Grid>
<Button>
<StackPanel Orientation="Horizontal">
<Image Source="{Binding ElementName=ImageButtonUserControl, Path=Image}" />
<TextBlock Text="{Binding ElementName=ImageButtonUserControl, Path=Text}" />
</StackPanel>
</Button>
</Grid>
</UserControl>
Now I want to use these Control in my view:
<uc:ImageButton Name="Cancel" Image="/Images/Icons/cancel_16x16.png" Text="Abbrechen" Margin="3" />
When I want to open my view (in my case it's opened as a dialog) it doesn't work. The View does not openend.
When I remove the Name-Attribute everthing is fine, but the Button have no binding to an action. Can anyone tell me what I have to do for a correct binding? A regular Button worked.

You are on a completely wrong way. You shouldn't create a user control for such a simple modification. You need to create a DataTemplate and use it for a Button.ContentTemplate. First you need to define a helper type for button content:
public class ImageButtonContent
{
public BitmapImage Image { get; set; }
public string Label { get; set; }
}
After that you can use it for DataTemplate:
<Window x:Class="Trys.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:Trys="clr-namespace:Trys"
Title="MainWindow"
Height="350"
Width="525">
<Window.Resources>
<Trys:ImageButtonContent x:Key="YourImageButtonHere"
Label="Your ImageButtonHere">
<Trys:ImageButtonContent.Image>
<BitmapImage UriSource="your-icon.png" />
</Trys:ImageButtonContent.Image>
</Trys:ImageButtonContent>
<DataTemplate x:Key="ImageButton"
DataType="{x:Type Trys:ImageButtonContent}">
<StackPanel Orientation="Horizontal">
<Image Source="{Binding Image}"
Margin="5" />
<TextBlock Text="{Binding Label}"
VerticalAlignment="Center"
Margin="10,0,0,0" />
</StackPanel>
</DataTemplate>
</Window.Resources>
<Grid>
<Button ContentTemplate="{StaticResource ImageButton}"
Content="{StaticResource YourImageButtonHere}"
Height="50"
Width="250" />
</Grid>
</Window>
I used a resource for an object, but you can use a property on your ViewModel. The result is:
And this just a normal button. You can use for it all power of Caliburn.Micro conventions like Click event default binding. Enjoy!