CODEWITHSUNDEEP
c#wpfxamlevent-handling
Kytopgun
Kytopgun

Reputation: 33

Event handlers not working in xaml

I have a TextBox in my page. That has INotifyChangeProperty

All the event handlers (LostFocus, KeyDown, KeyUp) will not fire. Behind the XAML I have C# code. 

private void TextBox_KeyUp_For_Decimal(object sender, KeyEventArgs e)
{
}

Here is the XAML code

<Grid Visibility="{Binding FreeInput, Converter={StaticResource  BoolToVisibilityConverter}}">
   <Grid.Resources>
      <TextBox 
         x:Key="StringDefaultPresenter" 
         x:Shared="False" 
         Text="{Binding Default, UpdateSourceTrigger=LostFocus}" CommandManager.PreviewExecuted="TextBox_PreviewExecuted" 
         LostFocus="Update_Default" 
         KeyDown="TextBox_KeyDown_For_String"/>
      <TextBox 
         x:Key="NumberDefaultPresenter" 
         x:Shared="False" 
         Text="{Binding Default, UpdateSourceTrigger=LostFocus}"
         CommandManager.PreviewExecuted="TextBox_PreviewExecuted" 
         LostFocus="Update_Default" 
         KeyDown="TextBox_KeyDown_For_Decimal" 
         KeyUp="TextBox_KeyUp_For_Decimal"/>
      <CheckBox 
         x:Key="BooleanDefaultPresenter" 
         x:Shared="False" 
         HorizontalAlignment="Center" 
         VerticalAlignment="Center" 
         LostFocus="Update_Default" 
         IsChecked="{Binding Default, Converter={l:DefaultValueConverter}, UpdateSourceTrigger=LostFocus}"/>
      <DatePicker 
         x:Key="DateTimeDefaultPresenter" 
         x:Shared="False" 
         SelectedDate="{Binding Default, Converter={l:DefaultValueConverter}, UpdateSourceTrigger=LostFocus}" 
         LostFocus="Update_Default"/>
      <Style x:Key="DefaultPresenterStyle" x:Shared="False" TargetType="ContentControl">
         <Style.Triggers>
            <DataTrigger Binding="{Binding DataType}" Value="{x:Static l:DataType.STRING}">
               <Setter Property="Content" Value="{StaticResource StringDefaultPresenter}"/>
            </DataTrigger>
            <DataTrigger Binding="{Binding DataType, Converter={l:EnumMatchToBoolConverter}, ConverterParameter={StaticResource NumberDataType}}" Value="True">
               <Setter Property="Content" Value="{StaticResource NumberDefaultPresenter}"/>
            </DataTrigger>
            <DataTrigger Binding="{Binding DataType}" Value="{x:Static l:DataType.BOOLEAN}">
               <Setter Property="Content" Value="{StaticResource BooleanDefaultPresenter}"/>
            </DataTrigger>
            <DataTrigger Binding="{Binding DataType}" Value="{x:Static l:DataType.DATE_TIME}">
               <Setter Property="Content" Value="{StaticResource DateTimeDefaultPresenter}"/>
            </DataTrigger>
         </Style.Triggers>
      </Style>
   </Grid.Resources>
   <ContentControl Style="{StaticResource DefaultPresenterStyle}"/>
</Grid>

This was working before I added x:Keys to the textboxes and added styles.

Upvotes: 0

Views: 1288

Answers (1)

Kytopgun
Kytopgun

Reputation: 33

Found the problem. Somehow because of XAML virtualization the handlers are not attached to the events.Setting them explicitly using styles solves the problem.

Like so add this to a TextBox or in this case a ComboBox

      <ComboBox
         x:Key="StringLengthPresenter" x:Shared="False"
         SelectedItem="{Binding Length, UpdateSourceTrigger=PropertyChanged}">
         <ComboBox.Style>
           <Style TargetType="ComboBox">
             <EventSetter Event="SelectionChanged" Handler="Length_SelectionChanged"/>
           </Style>
         </ComboBox.Style>

Upvotes: 1

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