Create DataTemplate in codebehind
How do i add controls to datatemplates programmatically?
For Example. Below I've c开发者_高级运维reated TextBlock and DataTemplate.
TextBlock text = new TextBlock();
DataTemplate template = new DataTemplate();
Now I need to add TextBlock to DataTemplate. How to achieve this?
I know that there are other ways of addind data template in code behind 1. create a data template in XAML and load it on code behind 2. create and add using XamlParser
but i need to do in the way i showed in example.
Need some help.
Although Archedius's method works, officially it is deprecated and instead recommended way to programmatically create a template is to load XAML from a string or a memory stream using the Load method of the XamlReader class like this...
public DataTemplate Create(Type type)
{
StringReader stringReader = new StringReader(
@"<DataTemplate
xmlns=""http://schemas.microsoft.com/winfx/2006/xaml/presentation"">
<" + type.Name + @" Text=""{Binding " + ShowColumn + @"}""/>
</DataTemplate>");
XmlReader xmlReader = XmlReader.Create(stringReader);
return XamlReader.Load(xmlReader) as DataTemplate;
}
Official line taken from msdn: http://msdn.microsoft.com/en-us/library/system.windows.frameworkelementfactory.aspx
Code example from Fredrik Hedblad's post here: Problems with XamlReader generating DataTemplate
You have first to declare a DataTemplate:
DataTemplate template = new DataTemplate { DataType = typeof(< Type of the object the template refers>) };
Then declare a layout panel like StackPanel in this way
FrameworkElementFactory stackPanelFactory = new FrameworkElementFactory(typeof(StackPanel));
stackPanelFactory.SetValue(StackPanel.OrientationProperty, Orientation.Vertical);
and finally attach the TextBlock piece at it:
FrameworkElementFactory title = new FrameworkElementFactory(typeof(TextBlock));
title.SetBinding(TextBlock.TextProperty, new Binding("< name of your binding >"));
stackPanelFactory.AppendChild(title);
in order to display the StackPanel created in this way you have to attach it to the VisualTree:
template.VisualTree = stackPanelFactory;
Hope it helps! :)
I know it is an work-around, but I published a tip in code project (http://www.codeproject.com/Tips/808808/Create-Data-and-Control-Templates-using-Delegates) that allows you to create a data-template using a delegate. For example:
TemplateGenerator.CreateDataTemplate(() => new TextBox());
This will be enough to create a datatemplate that creates a new textbox. If you want a binding too, it could be written like:
TemplateGenerator.CreateDataTemplate
(
() =>
{
var result = new TextBox();
result.SetBinding(TextBox.TextProperty, "PathForTheBinding");
return result;
}
);
The code of the TemplateGenerator is the following:
/// <summary>
/// Class that helps the creation of control and data templates by using delegates.
/// </summary>
public static class TemplateGenerator
{
private sealed class _TemplateGeneratorControl:
ContentControl
{
internal static readonly DependencyProperty FactoryProperty = DependencyProperty.Register("Factory", typeof(Func<object>), typeof(_TemplateGeneratorControl), new PropertyMetadata(null, _FactoryChanged));
private static void _FactoryChanged(DependencyObject instance, DependencyPropertyChangedEventArgs args)
{
var control = (_TemplateGeneratorControl)instance;
var factory = (Func<object>)args.NewValue;
control.Content = factory();
}
}
/// <summary>
/// Creates a data-template that uses the given delegate to create new instances.
/// </summary>
public static DataTemplate CreateDataTemplate(Func<object> factory)
{
if (factory == null)
throw new ArgumentNullException("factory");
var frameworkElementFactory = new FrameworkElementFactory(typeof(_TemplateGeneratorControl));
frameworkElementFactory.SetValue(_TemplateGeneratorControl.FactoryProperty, factory);
var dataTemplate = new DataTemplate(typeof(DependencyObject));
dataTemplate.VisualTree = frameworkElementFactory;
return dataTemplate;
}
/// <summary>
/// Creates a control-template that uses the given delegate to create new instances.
/// </summary>
public static ControlTemplate CreateControlTemplate(Type controlType, Func<object> factory)
{
if (controlType == null)
throw new ArgumentNullException("controlType");
if (factory == null)
throw new ArgumentNullException("factory");
var frameworkElementFactory = new FrameworkElementFactory(typeof(_TemplateGeneratorControl));
frameworkElementFactory.SetValue(_TemplateGeneratorControl.FactoryProperty, factory);
var controlTemplate = new ControlTemplate(controlType);
controlTemplate.VisualTree = frameworkElementFactory;
return controlTemplate;
}
}
And it has a method for ControlTemplates too.
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