Is it possible to bind something to a property of a control in a data template entirely in XAML? The following code is a simplified version of the problem I'm running into. I'd like the text of the TextBlock (displayName) to be updated as the user types in the TextBox located in the DataTemplate.
<Window x:Class="WpfApplication4.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:WpfApplication4="clr-namespace:WpfApplication4"
Title="Window1" Height="300" Width="300">
<Window.Resources>
<DataTemplate DataType="{x:Type WpfApplication4:Foo}">
<TextBox Text="{Binding Path=Name}" />
</DataTemplate>
<WpfApplication4:Foo x:Key="testObject" Name="This is a test" />
</Window.Resources>
<StackPanel>
<TextBlock x:Name="displayName" Margin="5" />
<ContentControl x:Name="contentControl" Margin="5" Content="{StaticResource testObject}" />
</StackPanel>
No, at least, not from XAML. You could write code to traverse the visual tree and find the element you want to bind to, but that would be nasty.
But in your particular example, would it not make sense to just bind the TextBlock to the same data object (Foo instance)?
Related
EDIT:
Here is a small sample Solution (VS 2013) showing my exact problem: nakkvarr.net/TestApp.zip
I have two views:
MainView
EmployeeView
I want my EmployeeView to reference the MainViewModel property "employees".
I tried this:
<DockPanel DataContext="{Binding DataContext.MainViewModel,
RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type EmployeeLisViewModel}}}">
But all I get is the Error: EmployeeListViewModel ist not supported in WPF ?!
(EmployeeListViewModel is also the name of the property of my MainViewModel)
The thing is:
My MainView has some menu items. One is for sorting the employee list, which is inside my UserControl. My UserControl ViewModel contains the Commands for sorting.
EDIT:
I changed it to vm:EmployeeListViewModel ... now the error is gone...but now I don't seem to get access to the ViewModel :/
<ia:InvokeCommandAction Command="{Binding LoadEmployeesCommand}"
Does not trigger, no emplyees get loaded. When I use the ViewModel directly, it works just fine.
MainWindow.xaml
<Window x:Class="de.XXX.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:controls="clr-namespace:de.XXX.Views"
xmlns:vm="clr-namespace:de.XXX.ViewModel"
Icon="/Images/App.ico"
Style="{StaticResource MainWindowStyle}"
Title="MainWindow">
<DockPanel DataContext="{Binding MainViewModel, Source={StaticResource Locator}}">
<Menu DockPanel.Dock="Top">
...
</Menu>
<controls:EmployeeListView DockPanel.Dock="Bottom" DataContext="{Binding EmployeeListViewModel}" />
</DockPanel>
</Window>
EmployeeListView.xaml //not model, copy & paste error x_X
<UserControl x:Class="de.XXX.Views.EmployeeListView"
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"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:vm="clr-namespace:de.XXX.ViewModel"
xmlns:ia="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
mc:Ignorable="d"
d:DesignHeight="350" d:DesignWidth="350">
<DockPanel DataContext="{Binding MainViewModel,
RelativeSource={RelativeSource FindAncestor,
AncestorType={x:Type vm:EmployeeListViewModel}}}">
<ListBox DockPanel.Dock="Bottom" x:Name="EmployeeList" ItemsSource="{Binding EmployeeList}" ScrollViewer.CanContentScroll="False" />
<ia:Interaction.Triggers>
<ia:EventTrigger EventName="Loaded">
<ia:InvokeCommandAction Command="{Binding LoadEmployeesCommand}" />
</ia:EventTrigger>
</ia:Interaction.Triggers>
</DockPanel>
</UserControl>
If you modify your SubControl to below, this should work.
<Grid DataContext="{Binding Path=DataContext.SubVM, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type Window}}}">
I have a hint on what you are trying to achieve and I guess you have missed some details on Binding especially on other underlying properties needed to be set. This part is working based on the given code. But then, there are numerous ways in making it better. Good luck.
I think there might be a combination of misunderstandings here! Your UserControl has
x:Class="de.XXX.Views.EmployeeListView"
defined as the class name in xaml. However, you're also saying that the file is named EmployeeListViewModel.xaml? A .xaml file should never be named a viewmodel. I believe you should have MainWindow.xaml, EmployeeListView.xaml, MainWindowViewModel.cs, and EmployeeListViewModel.cs, is this the case?
Also, in your MainWindow.xaml, you're already setting the datacontext of your EmployeeListView usercontrol:
<controls:EmployeeListView DockPanel.Dock="Bottom" DataContext="{Binding EmployeeListViewModel}" />
This implies to me that your class structure is that MainViewModel contains an instance of the EmployeeListViewModel... is this true?
If all the above is true, then this part of your UserControl xaml does not make sense:
<DockPanel DataContext="{Binding MainViewModel,
RelativeSource={RelativeSource FindAncestor,
AncestorType={x:Type vm:EmployeeListViewModel}}}">
Whether EmployeeListViewModel is actually your view and not your viewmodel, the property "MainViewModel" does not exist on EmployeeListViewModel, so the binding will never work.
If you're trying to have a reference to your Window's DataContext, MainViewModel, within your UserControl, a possible way to do this is:
MainWindow.xaml:
<controls:EmployeeListView DockPanel.Dock="Bottom" DataContext="{Binding}" />
This should set the DataContext of your EmployeeListView to MainViewModel. Then, in your EmployeeListView, you can do this:
<UserControl x:Class="de.XXX.Views.EmployeeListView"
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"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:vm="clr-namespace:de.XXX.ViewModel"
xmlns:ia="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
mc:Ignorable="d"
d:DesignHeight="350" d:DesignWidth="350">
<DockPanel
<ListBox DockPanel.Dock="Bottom" x:Name="EmployeeList" ItemsSource="{Binding EmployeeList}" ScrollViewer.CanContentScroll="False" />
<ia:Interaction.Triggers>
<ia:EventTrigger EventName="Loaded">
<ia:InvokeCommandAction Command="{Binding EmployeeListViewModel.LoadEmployeesCommand}" />
</ia:EventTrigger>
</ia:Interaction.Triggers>
</DockPanel>
</UserControl>
There's a lot of assumptions about your views and viewmodels I made for this answer. I hope this at least helps. If it doesn't make any sense, please post your viewmodels as well :)
After thoroughly reading the documentation on flowdocuments (in WPF) it seems as though flowdocument does not easily support databinding. PLEASE say this is not true! I have a listbox using the sample data in Expression Blend and I inserted a textblock into the flowdocument. The textblock (text property) is databinded to the string data in the listbox. After running the project I would expect that the textblock text changes as the listbox selection changes, but nothing happens. Databinding is not working. What is the easiest way to make databinding work with flowdocument?
Here is the XAML.
<Window
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
x:Class="WpfApplication1.MainWindow"
x:Name="Window"
Title="MainWindow"
Width="640" Height="480">
<Window.Resources>
<DataTemplate x:Key="ItemTemplate">
<StackPanel>
<TextBlock Text="{Binding Property1}"/>
</StackPanel>
</DataTemplate>
</Window.Resources>
<Grid x:Name="LayoutRoot" DataContext="{Binding Source={StaticResource SampleDataSource}}">
<FlowDocumentScrollViewer Margin="120,64,256,126">
<FlowDocument>
<Paragraph><Run Text="Only A Test"/><InlineUIContainer>
<TextBlock TextWrapping="Wrap" Text="{Binding Collection[0].Property1}" Height="56" Width="112"/>
</InlineUIContainer></Paragraph>
</FlowDocument>
</FlowDocumentScrollViewer>
<ListBox ItemTemplate="{DynamicResource ItemTemplate}" ItemsSource="{Binding Collection}" Margin="0,83.847,52,62.153" HorizontalAlignment="Right" Width="200"/>
</Grid>
</Window>
According to this Microsoft documentation in April 2009, this is not possible:
While there are many great features in flow documents, if your documents are generated from dynamic data, you have a bit of a problem: there is no support for data binding in flow documents. The flow document elements (Section, Table, Run, Paragraph and the like) are dependency objects, but don't define any dependency properties that would allow you to dynamically change or generate content.
I have a custom Tab Control that I have created, but I am having an issue. I have an Editable TextBox as part of the custom TabControl View.
<Controls:EditableTextControl x:Name="PageTypeName"
Style="{StaticResource ResourceKey={x:Type Controls:EditableTextControl}}" Grid.Row="0" TabIndex="0"
Uid="0"
AutomationProperties.AutomationId="PageTypeNameTextBox"
AutomationProperties.Name="PageTypeName"
Visibility="{Binding ElementName=PageTabControl,Path=ShowPageType}">
<Controls:EditableTextControl.ContextMenu>
<ContextMenu x:Name="TabContextMenu">
<MenuItem Header="Rename Page Type" Command="{Binding Path=PlacementTarget.EnterEditMode, RelativeSource={RelativeSource AncestorType=ContextMenu}}"
AutomationProperties.AutomationId="RenamePageTypeMenuItem"
AutomationProperties.Name="RenamePageType"/>
<MenuItem Header="Delete Page Type" Command="{Binding Path=PageTypeDeletedCommand}"
AutomationProperties.AutomationId="DeletePageTypeMenuItem"
AutomationProperties.Name="DeletePageType"/>
</ContextMenu>
</Controls:EditableTextControl.ContextMenu>
<Controls:EditableTextControl.Content>
<!--<Binding Path="CurrentPageTypeViewModel.Name" Mode="TwoWay"/>-->
<Binding ElementName="PageTabControl" Path="CurrentPageTypeName" Mode ="TwoWay"/>
</Controls:EditableTextControl.Content>
</Controls:EditableTextControl>
In the Content section I am binding to a Dependency Prop called CurrentPageTypeName. This Depedency prop is part of this custom Tab Control.
public static DependencyProperty CurrentPageTypeNameProperty = DependencyProperty.Register("CurrentPageTypeName", typeof(object), typeof(TabControlView));
public object CurrentPageTypeName
{
get { return GetValue(CurrentPageTypeNameProperty) as object; }
set { SetValue(CurrentPageTypeNameProperty, value); }
}
In another view, where I am using the custom TabControl I then bind my property, with the actual name value, to CurrentPageTypeName property as seen below:
<Views:TabControlView Grid.Row="0" Name="RunPageTabControl"
TabItemsSource="{Binding RunPageTypeViewModels}"
SelectedTab="{Binding Converter={StaticResource debugConverter}}"
CurrentPageTypeName="{Binding Path=RunPageName, Mode=TwoWay}"
TabContentTemplateSelector="{StaticResource tabItemTemplateSelector}"
SelectedIndex="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type UserControl}}, Path=DataContext.SelectedTabIndex}"
ShowPageType="Hidden" >
<!--<Views:TabControlView.TabContentTemplate>
<DataTemplate DataType="{x:Type ViewModels:RunPageTypeViewModel}">
<RunViews:RunPageTypeView/>
</DataTemplate>
</Views:TabControlView.TabContentTemplate>-->
</Views:TabControlView>
My problem is that nothing seems to be happening. It is grabbing its Content from the Itemsource, and not from my chained Dependency props. Is what I am trying even possible? If so, what have I done wrong.
Thanks for looking.
Unless I'm missing something this is definitely possible. Here is a simplified working example.
User control with a dependency property named TestValue, containing a TextBox bound to this property:
<UserControl x:Class="TestApp.TestControl" 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"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008" mc:Ignorable="d" d:DesignHeight="300" d:DesignWidth="300"
x:Name="TestControlName">
<Grid>
<TextBox Text="{Binding ElementName=TestControlName, Path=TestValue, Mode=TwoWay}"/>
</Grid>
</UserControl>
A different view using this user control, binding the above mentioned dependency property to something:
<Window x:Class="TestApp.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:TestApp="clr-namespace:TestApp" Title="MainWindow"
Height="350" Width="525">
<StackPanel>
<TestApp:TestControl TestValue="{Binding ElementName=SourceTextBox, Path=Text, Mode=TwoWay}" />
<TextBox Name="SourceTextBox" />
</StackPanel>
</Window>
It sounds that the issue is somewhere in the part of the code you have not posted (e.g. wrong name used in Content binding).
I think you already solved this yourself for the "SelectedIndex" property. Just do the same thing for the "CurrentPageType" property i.e. use RelativeSource
I have a ContentControl in a RadTileView. If I put in some hard coded text into the content property it works fine. (code below)
<ContentControl Grid.Row="2" Grid.Column="0" Content="Hello World"></ContentControl>
That works...if I put the content into the UserControl.Resources section my application freezes up and displays nothing.
<ContentControl Grid.Row="2" Grid.Column="0" Content="{StaticResource TabControlContent}"></ContentControl>
<UserControl.Resources>
<TextBlock x:Key="TabControlContent" Text="hello world"></TextBlock>
</UserControl.Resources>
Ultimately I would like to have the context be a RadTabControl..but for now Id settle on just having that textblock render.
To get a string into your ContentControl you would, add
xmlns:sys="clr-namespace:System;assembly=mscorlib"
to your usings. Then add this
<UserControl.Resources>
<sys:String x:Key="SingleString">Hello World</sys:String>
</UserControl.Resources>
Which would allow
<ContentControl Content="{Binding Source={StaticResource SingleString}}"/>
Hope this helps.
Sorry for this, I've just started programming with wpf. I can't seem to figure out why the following xaml displays "System.Xml.XmlElement" instead of the actual xml node content. This is displayed 5 times in the listbox whenever I run it. Not sure where I'm going wrong...
<Window x:Class="TestBinding.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Window1" Height="300" Width="300">
<Window.Resources>
<XmlDataProvider x:Key="myXmlSource" XPath="/root">
<x:XData>
<root xmlns="">
<name>Steve</name>
<name>Arthur</name>
<name>Sidney</name>
<name>Billy</name>
<name>Steven</name>
</root>
</x:XData>
</XmlDataProvider>
<DataTemplate x:Key="shmooga">
<TextBlock Text="{Binding}"/>
</DataTemplate>
</Window.Resources>
<Grid>
<ListBox ItemTemplate="{StaticResource shmooga}"
ItemsSource="{Binding Source={StaticResource myXmlSource}, XPath=name}">
</ListBox>
</Grid>
</Window>
Any help would be very much appreciated. Thanks!
Your ItemsSource Binding is returning the collection of 'name' elements. These are of type XmlElement. This is done because it allows bindings to get at other properties of the XmlElement, but means that if you textually display the result of the binding then you get System.Xml.XmlElement rather than the textual content.
To get the textual content, add an additional XPath to your ItemTemplate binding to specify that the TextBlock.Text property should bind specifically to the text of the element, not the element object itself:
<DataTemplate x:Key="shmooga">
<TextBlock Text="{Binding XPath=text()}"/> <!-- Note XPath on Binding -->
</DataTemplate>