使用 SimpleCommand 时，mahapps.metro TextBoxHelper.ButtonCommand 不触发

Question

I'm trying to get a SearchMetroTextBox TextBoxHelper.ButtonCommand event to fire and am not having any luck. Here's the steps I took.

1. From the Demo application, I build MahApps.Metro.Resources.dll and referenced that.

2. From the Demo application of mahapps.metro, I copied the following class:

   public class SimpleCommand : ICommand
   {
   ... implementation ...
   }

3. I didn't want the search icon, but instead a file browse icon, so I made the following style:

    <Style x:Key="BrowseMetroTextBox" TargetType="{x:Type TextBox}" BasedOn="{StaticResource SearchMetroTextBox}"> <Style.Triggers> <Trigger Property="Controls:TextBoxHelper.HasText" Value="False"> <Setter Property="Controls:TextBoxHelper.Watermark" Value="Select save location..." /> </Trigger> </Style.Triggers> <Setter Property="Controls:TextBoxHelper.ButtonTemplate"> <Setter.Value> <ControlTemplate TargetType="{x:Type Button}"> <Grid Background="{TemplateBinding Background}"> <Grid x:Name="contentPresenter" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" Opacity="0.75"> <Canvas Width="15" Height="15" Clip="F1 M 0,0L 76,0L 76,76L 0,76L 0,0"> <!-- x:Key="appbar_folder_ellipsis"--> <Path Width="15.7781" Height="15.7781" Stretch="Fill" Fill="{DynamicResource AccentColorBrush}" Data="F1 M 21,30.0001L 55.9999,30.0001L 55.9999,50L 21,50L 21,30.0001 ZM 52,28L 37,28C 38,25 39.4999,24.0001 39.4999,24.0001L 50.75,24C 51.3023,24 52,24.6977 52,25.25L 52,28 ZM 53.5,52C 54.8807,52 56,53.1193 56,54.5C 56,55.8807 54.8807,57 53.5,57C 52.1193,57 51,55.8807 51,54.5C 51,53.1193 52.1193,52 53.5,52 ZM 46.5,52C 47.8807,52 49,53.1193 49,54.5C 49,55.8807 47.8807,57 46.5,57C 45.1193,57 44,55.8807 44,54.5C 44,53.1193 45.1193,52 46.5,52 ZM 39.5,52C 40.8807,52 42,53.1193 42,54.5C 42,55.8807 40.8807,57 39.5,57C 38.1193,57 37,55.8807 37,54.5C 37,53.1193 38.1193,52 39.5,52 Z " /> </Canvas> </Grid> </Grid> <ControlTemplate.Triggers> <Trigger Property="IsPressed" Value="True"> <Setter Property="Foreground" Value="{DynamicResource WhiteBrush}" /> <Setter Property="Background" Value="{DynamicResource AccentColorBrush}" /> </Trigger> </ControlTemplate.Triggers> </ControlTemplate> </Setter.Value> </Setter> </Style>

4. From the Demo application I copied the TextBoxButtonCmdWithParameter, renaming it to FileBrowseCommand.

5. I created the following TextBoxes (note, one is my browse text box and one is standard search textbox):

    <TextBox HorizontalAlignment="Stretch" Height="23" VerticalAlignment="Top" Margin="10,26,10,0" Name="employeeLocation" Controls:TextBoxHelper.ButtonCommand="{Binding FileBrowseCommand, Mode=OneWay}" Controls:TextBoxHelper.ButtonCommandParameter="{Binding ElementName=employeeLocation, Path=Text}" Style="{StaticResource BrowseMetroTextBox}"/> <TextBox HorizontalAlignment="Stretch" Height="23" VerticalAlignment="Top" Margin="10,83,10,0" Name="adminLocation" Controls:TextBoxHelper.ButtonCommand="{Binding FileBrowseCommand, Mode=OneWay}" Controls:TextBoxHelper.ButtonCommandParameter="{Binding ElementName=adminLocation, Path=Text}" Style="{StaticResource SearchMetroTextBox}"/>

However, when I click the search or browse button, I never hit the event handler. Is there something else I'm missing?

Answer 1

I have encountered the same problem, I solved it by changing Controls:TextBoxHelper.ButtonCommand to a nested element in my textbox:

<Controls:TextBoxHelper.ButtonCommand>
    <Binding Path="FileBrowseCommand" Mode="OneWay" />
</Controls:TextBoxHelper.ButtonCommand>`

Answer 2

This will happen, if the command that is bound to the Textbox Button does not have the right type. It needs to have the Textbox as input parameter. Also Textbox must be from System.Windows.Controls, not from System.Windows.Forms. The following should work when defined in your data context:

public ReactiveCommand<System.Windows.Controls.TextBox, Unit> YourCommandName { get; private set; }

YourCommandName = ReactiveCommand.Create((System.Windows.Controls.TextBox textBox) =>
{
   // your command code
});