creating complex lookless controls

creating complex lookless controls

• ddlam

  but in this case I want the code behind to be part of the definition of the custom control. As the entire control template can be swapped out I need any code-behind to exist within the custom control class definition.
  
  

• Kerry_Dixon

  Most likely for designer support. I did check as well and they don't cause any automatic error generation. So it's basically a way to tell inheritors/designers what your control template expects. You have to do the checking in your OnApplyTemplate override yourself.
  
  

• Julien Couvreur

  I dont know if it will help your situation, instead of using textbox you might be able to use FrameworkElement.lostfocus or soimething like that

  
  
  

• PublicError

  I've tried to make my PowerGrid as lookless as possible...although it really wouldn't make sense being much more than a grid. Go to http://www.codeplex.com/Wiki/View.aspx ProjectName=wpftoolbelt to download the source and see what I mean. I don't create any visual elements within the control.

  Also just use Reflector to look at some of the controls that come with the library.

  
  
  

• John Dekker

  Thanks Mike, I Think thats exactly what I'm looking for. Are there any examples of creating complicated lookless controls out there I think I've figured a lot of it out, but its been tough going.
  
  

• Pojev

  Yeah, thats where I'm doing the checking now. I assume that will fire on a theme or other template change too, so that events can be rehooked. Thanks for the advice again.
  
  

• Atul Kulkarni

  you should be able to hookup

  TextBox.LostFocus="txt_LostFocus" on the panel holding those TextBoxes, something like this should work

  <StackPanel Name="sp1" TextBox.LostFocus="txt_LostFocus">

  <TextBox Text="text1" Name="txt1"></TextBox>

  <TextBox Text="text2" Name="txt2"></TextBox>

  </StackPanel>

  void txt_LostFocus(object sender, RoutedEventArgs e){

  MessageBox.Show((e.OriginalSource as TextBox).Name);

  }

  
  
  

• globelin

  Use TemplateParts.

  Give each of the child controls that you need to be present in your control's template a name in your template like PART_TextControl1.
  Add a TemplatePartAttribute to your control that specifies the name of the required control and its type.

  Now in your constructor add a handler to your control's Loaded event that gets a handle to your control parts and assigns handlers to their LostFocus events.

  [TemplatePart(Name="PART_TextControl1" Type=typeof(TextBox))] public class MyControl: Control { public MyControl() { this.Loaded+=new RoutedEventHandler(OnLoaded); } private void OnLoaded(Object Source, RoutedEventArgs e) { TextBox TextControl1=Template.FindName("PART_TextControl1") as TextBox; if(TextControl1!=null) { TextControl1.LostFocus+=new RoutedEventHandler(TextControl1_LostFocus); } } protected virtual void TextControl1_LostFocus(Object sender, RoutedEventArgs e) { //Perform whatever actions you want here e.OriginalSource is your TextBox } }

  By placing the TemplatePartAttribute on your class, you are basically saying that part of the code contract is that the template used for this control must have an element named PART_TextControl1 and it must be of typ TextBox. I believe that the WPF runtime will throw an exception saying as much for you but if not, throw one within your OnLoaded event.

  
  
  

• &amp;#40643;&amp;#27859;&amp;#37327; Jeremy Wong

  As far as I can tell (from empirical tests) the use of this attribute doesnt create a compile time or run time error if that template part doesnt exist in the template.
  
  I'm wondering what these attributes are for then. Designer support Some unimplimented error handling
  
  -G
  
  
• creating complex lookless controls