The XAML below is incorrect, but it represents what I'm trying to do. I'm fairly new to WPF, but I want to know if something like this doable without instead declaring the instance in the code behind?
<ListBox Name="lbInstalledFonts" VerticalContentAlignment="Center" DisplayMemberPath="Name" ItemsSource="{Binding Source={new System.Drawing.Text.InstalledFontCollection().Familes}}" />
To elaborate, I only need the list of System.Drawing.Text.InstalledFontCollection().Familes for this ListBox. That's it. So I was thinking I could do it entirely through the XAML in a similar way to how you could bind to a DataSource in ASP.NET (through the use of <% and %> in the aspx/ascx files)? Is this at all possible? I did some searching but didn't have much luck.
Yes, it is possible:
<Window x:Class="HelpStackOverflow.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:drawing="clr-namespace:System.Drawing.Text;assembly=System.Drawing"
Title="MainWindow" Height="350" Width="525">
<Window.Resources>
<drawing:InstalledFontCollection x:Key="InstalledFontCollection" />
</Window.Resources>
<Grid>
<ListBox Name="lbInstalledFonts"
VerticalContentAlignment="Center"
DisplayMemberPath="Name"
ItemsSource="{Binding Source={StaticResource InstalledFontCollection}, Path=Families}" />
</Grid>
</Window>
Related
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 would like to add a specific instance of a class to the resources of a page then use that class as a converter, so in my page constructor I put:
this.Resources.Add("converterASD", new ASDConverter());
then bind to it like this:
<ListBox ItemsSource="{Binding Converter={StaticResource converterASD}}"/>
but I keep getting this exception:
Provide value on 'System.Windows.Markup.StaticResourceHolder' threw an
exception.
I'm a bit new to WPF, any advice would be appreciated.
We could use more information from the exception.
Two suggestions:
Make sure that you add the resource before the call to InitializeComponent().
Try switching it to a dynamic resource.
You can declare the Converter you would like to use in the resource section of the page like the following example. (I recommend you declare the converter in XAML instead of the code-behind)
Example:
<UserControl x:Class="Views.ConverterExample"
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">
<UserControl.Resources>
<BooleanToVisibilityConverter x:Key="BoolToVisibilityConverter" />
</UserControl.Resources>
<Grid>
<CheckBox x:Name="VisibilityController" IsThreeState="False" />
<ListBox
Visibility="{Binding ElementName=VisibilityController, Path=IsChecked,Converter={StaticResource BoolToVisibilityConverter}}"
Height="100" Width="100" BorderBrush="Red" BorderThickness="1" />
</Grid>
</UserControl>
I'm relatively new to wpf and I quite don't understand binding yet.
I want to have several combo boxes in my application with the same items. The basic solution would be to copy paste but that just isn't good practice. So I thought to put a static resource with the content I want and bind all combo boxes to it. It compiles and runs well but the combo box is empty.
Here's the code:
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<ItemsControl x:Key="Validations">
<ItemsControl.Items>
<ComboBoxItem>String</ComboBoxItem>
<ComboBoxItem>Numeric</ComboBoxItem>
</ItemsControl.Items>
</ItemsControl>
and here's the combo box:
<ComboBox ItemsSource="{Binding Source={StaticResource Validations}}"/>
I know the solution for this is probably simple but I haven't figured it out yet. I'll keep trying ;)
Thanks
Make the resource a list of strings, not a visual element, then use the StaticResource extension to assign it to the ItemsSource property, like so:
<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:sys="clr-namespace:System;assembly=mscorlib"
Title="MainWindow" Height="350" Width="525">
<Window.Resources>
<x:ArrayExtension x:Key="Data" Type="{x:Type sys:String}">
<sys:String>String1</sys:String>
<sys:String>String2</sys:String>
<sys:String>String3</sys:String>
</x:ArrayExtension>
</Window.Resources>
<Grid>
<StackPanel>
<ComboBox ItemsSource="{StaticResource Data}"/>
<ComboBox ItemsSource="{StaticResource Data}"/>
<ComboBox ItemsSource="{StaticResource Data}"/>
</StackPanel>
</Grid>
</Window>
Note the definition of the xmlns:sys namespace (maps to namespace System in assembly mscorlib) and the use of the x:ArrayExtension element to declare a simply array in XAML.
Given the following code:
<Window x:Class="WpfApplication76.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:col="clr-namespace:System.Collections;assembly=mscorlib"
Title="Window1" Height="300" Width="300">
<Window.Resources>
<CollectionViewSource x:Key="myCol">
<CollectionViewSource.Source>
<col:ArrayList>
<ListBoxItem>Uno</ListBoxItem>
<ListBoxItem>Dos</ListBoxItem>
<ListBoxItem>Tres</ListBoxItem>
</col:ArrayList>
</CollectionViewSource.Source>
</CollectionViewSource>
</Window.Resources>
<Grid>
<ListBox ItemsSource="{StaticResource myCol}" />
<ListBox ItemsSource="{Binding Source={StaticResource myCol}}" />
</Grid>
</Window>
In this example, the
<ListBox ItemsSource="{StaticResource myCol}" />
Gives me an error complaining that it cannot bind to a "CollectionViewSource" object.
But the other listbox:
<ListBox ItemsSource="{Binding Source={StaticResource myCol}}" />
binds perfectly fine.
So my question is why does one work and the other one does not? AT the end, aren't both ItenSources being set to the same "CollectionViewSource" object?
Thank you.
The ItemsSource property is of type IEnumerable. A CollectionViewSource is not an IEnumerable. CollectionViewSource's View property will give you an IEnumerable.
When you Bind to a CollectionViewSource the Binding is smart enough to grab the View property and actually bind to that. Maybe CollectionViewSource has a [DefaultBindingProperty] on it.
It boils down to the fact that when you go through the Binding you don't actually bind to the CollectionViewSource, but its View property.
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)?