Question

我正在尝试将上下文菜单添加到我创建的WPF用户控件中。菜单，图标和命令显示但在菜单中它显示为灰色，即使我已将CommandBinding_CanExecute设置为总是返回true。

这是XAML

<UserControl x:Class="KeyframePartialApp.ctrCell"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
         xmlns:local="clr-namespace:KeyframePartialApp"
         mc:Ignorable="d">

<UserControl.Resources>
    <RoutedUICommand x:Key="MakeKeyCell" Text="Make KeyCell" />
</UserControl.Resources>


<Border x:Name="bdrBackground" Width="14" Height="24" BorderBrush="{DynamicResource {x:Static SystemColors.ControlDarkDarkBrushKey}}" BorderThickness="1" Background="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}" >
    <Border.ContextMenu>
        <ContextMenu>
            <MenuItem Icon="{StaticResource imgKeyIcon}" Command="{StaticResource MakeKeyCell}"></MenuItem>
        </ContextMenu>
    </Border.ContextMenu>
    <Border.CommandBindings>
        <CommandBinding Command="{StaticResource MakeKeyCell}" CanExecute="CommandBinding_CanExecute" Executed="MakeKeyCell_Executed"></CommandBinding>
    </Border.CommandBindings>
    <Rectangle Width="10" Height="10" x:Name="rctIcon" />
</Border>

以下是

背后的代码

 public partial class ctrCell : UserControl
{
    private Cell _cell;

    public ctrCell(Cell cell)
    {
        _cell = cell;
        InitializeComponent();
        _cell.PropertyChanged += _cell_PropertyChanged;
        UpdateKeyCellImage();
    }

    private void _cell_PropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e)
    {
        if (e.PropertyName == "isKeyCell") UpdateKeyCellImage();
    }

    public void UpdateKeyCellImage()
    {
        if (_cell.isKeyCell)
        {
            rctIcon.Fill = (ImageBrush)Application.Current.Resources["ibKeycell"];
        }
        else
        {
            rctIcon.Fill = null;
        }
    }

    private void MakeKeyCell_Executed(object sender, ExecutedRoutedEventArgs e)
    {
        _cell.isKeyCell = true;

    }

    private void CommandBinding_CanExecute(object sender, CanExecuteRoutedEventArgs e)
    {
        if (!_cell.isKeyCell) e.CanExecute = true;
    }
}

}

Answer 1

这是：WPF custom command in context menu are disabled until any button clicked

的副本

赞同Simon D.的回答，为了完整起见，我也会在这里回答：

可以在此处找到更详细的解释： http://www.wpftutorial.net/RoutedCommandsInContextMenu.html

要解决您的问题，只需将CommandTarget添加到您的MenuItem：

<Border.ContextMenu>
    <ContextMenu>
        <MenuItem IsEnabled="True" 
                  Command="{StaticResource MakeKeyCell}"
                  CommandTarget="{Binding Path=PlacementTarget, 
                                          RelativeSource={RelativeSource FindAncestor, 
                                          AncestorType={x:Type ContextMenu}}}" />
    </ContextMenu>
</Border.ContextMenu>

使用RoutedUICommand将上下文菜单添加到wpf UserControl

1 个答案: