Can I create DataTemplate Programatically?

Question

Is it possible to create DataTemplate in code-behind?
And I want to add a Grid object as content of this DataTemplate.
Is this possible?

Answer 1

 

per SDK 'The 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.'

Answer 2

Hi lee,

can u provide me some code snippet for this?

Answer 3

something like this should work

Code Snippet

MemoryStream sr = null;

ParserContext pc = null;

string xaml = string.Empty;

xaml = "<DataTemplate><TextBlock Text=\"Some Text\"/></DataTemplate>";

sr = new MemoryStream(Encoding.ASCII.GetBytes(xaml));

pc = new ParserContext();

pc.XmlnsDictionary.Add("", "http://schemas.microsoft.com/winfx/2006/xaml/presentation");

pc.XmlnsDictionary.Add("x", "http://schemas.microsoft.com/winfx/2006/xaml");

DataTemplate datatemplate = (DataTemplate)XamlReader.Load(sr, pc);

this.Resources.Add("dt", datatemplate);

 

Answer 4

Hi,

Yes it is possible to create a DataTemplate programmatically but it is not very elegant. Have a look at the following code:

Code Snippet

DataTemplate template = new DataTemplate();

FrameworkElementFactory factory = new FrameworkElementFactory(typeof(StackPanel));

template.VisualTree = factory;

FrameworkElementFactory childFactory = new FrameworkElementFactory(typeof(Image));

childFactory.SetBinding(Image.SourceProperty, new Binding("Machine.Thumbnail"));

childFactory.SetValue(Image.WidthProperty, 170.0 ) ;

childFactory.SetValue(Image.HeightProperty, 170.0 ) ;

factory.AppendChild(childFactory);

childFactory = new FrameworkElementFactory(typeof(Label));

childFactory.SetBinding(Label.ContentProperty, new Binding("Machine.Descriiption"));

childFactory.SetValue(Label.WidthProperty, 170.0);

childFactory.SetValue(Label.HorizontalAlignmentProperty, HorizontalAlignment.Center);

factory.AppendChild(childFactory);

 

The following is taken from www.codeplex.com/Impilo

 

Here I added a StackPanel. Each item included a data bound image and a description of the image. I also set some properties (ie. Width, Height, etc).

 

Hope this helps...

 

Rudi Grobler

Answer 5

Hi Rudi,
Thanks for the reply. But I want to add an existing Grid object as a VisualTree.
Is it possible?

Answer 6

Yes, just replace StackPanel with Grid. I just tested it and it worked...

Answer 7

FYI, SDK says FrameworkElementFactory is Deprecated

Answer 8

I had a question about the sample that you provided here.  I am trying to do something similar about creating a data template programmatically, and the data template that I am trying to create has a button with an OnClick event described. Whenever i try to use the code above to create the data template, the runtime throws an exception saying that I cannot include an event handler.  Is there a way around this problem ??
Thanks
-alok

Answer 9

Your example is excellent.  I am trying to build up a more complex structure, which I've found is easy if I do something like:

WrapPanel wp = new WrapPanel();

TextBlock tb = new TextBlock();

tb.SetBinding(TextBlock.TextProperty, new Binding("HeaderText"));

wp.Children.Add(tb)

string xaml = XamlWriter.Save(wp);

... continue with your code.

 

However, the binding to the text property is lost by teh XamlWriter.Save call.  Is there a way to get something like XamlWriter to generate that xaml text as well?

Answer 10

ok i followed this procedure , i am able to display images alright . i was doing this to add images to a gridviewcolumn . i was able to do it for a single image so all the rows in the column had the same image . please suggest how to go about it when i different images for each row of the column.

Answer 11

I am analyzing the purposed solution but got stuck at one point. I need to use a convertor as well in a data template. I tried but couldn't get thru. Steps are as follows - i have created a multi value converter & need to use that as a StaticResource. I am not sure if I am missing anything. Kindly suggest. 

pc.XmlnsDictionary.Add("local", "clr-namespace:test");

StringBuilder xamlString = new StringBuilder();
xamlString.Append(@"<DataTemplate> ");

xamlString.Append(@"<DataTemplate.Resources> ");
xamlString.Append(@"<local:PatientConverter x:Key=""conv""/>");
xamlString.Append(@"</DataTemplate.Resources> ");

xamlString.Append(@"<Label Grid.Row=""3"" Grid.Column=""1"" >");
xamlString.Append(@"<Label.Content>");

xamlString.Append(@"<MultiBinding Converter=""{StaticResource conv}"">");

xamlString.Append(@"<Binding Path=""FName"" />");
xamlString.Append(@"<Binding Path=""LName"" />");
xamlString.Append(@"</MultiBinding>");
xamlString.Append(@"</Label.Content>");
xamlString.Append(@"</Label>");

Answer 12

I have got the answer. Actually I was missing the assembly in the declaration of local namespace.

pc.XmlnsDictionary.Add("local", "clr-namespace:test;assembly=test");

even below approach is working

xamlString.Append(@"<DataTemplate xmlns:local=""clr-namespace:test;assembly=test"" > ");

xamlString.Append(@"<DataTemplate.Resources> <local:PatientConverter x:Key=""_conv""/> ");

Thnx..

Answer 13

Thanks it really helpful..