C# WPF左键单击上下文菜单不';不要在第二次单击时松开
我已经为WPF按钮实现了一个新的行为,用于通过左键单击使用上下文菜单:C# WPF左键单击上下文菜单不';不要在第二次单击时松开,c#,.net,wpf,xaml,C#,.net,Wpf,Xaml,我已经为WPF按钮实现了一个新的行为,用于通过左键单击使用上下文菜单: public class LeftClickContextMenuButtonBehavior : Behavior<Button> { protected override void OnAttached() { base.OnAttached(); AssociatedObject.AddHandler(UIElement.MouseDownEvent, new
public class LeftClickContextMenuButtonBehavior : Behavior<Button>
{
protected override void OnAttached()
{
base.OnAttached();
AssociatedObject.AddHandler(UIElement.MouseDownEvent, new RoutedEventHandler(AssociatedObject_MouseDown), true);
}
void AssociatedObject_MouseDown(object sender, RoutedEventArgs e)
{
Button source = sender as Button;
if (source != null && source.ContextMenu != null)
{
source.ContextMenu.PlacementTarget = source;
source.ContextMenu.Placement = PlacementMode.Bottom;
source.ContextMenu.IsOpen = !source.ContextMenu.IsOpen;
}
}
protected override void OnDetaching()
{
base.OnDetaching();
AssociatedObject.RemoveHandler(UIElement.MouseDownEvent, new RoutedEventHandler(AssociatedObject_MouseDown));
}
}
public类LeftClickContextMenuButtonBehavior:Behavior
{
受保护的覆盖无效附加()
{
base.onatached();
AssociatedObject.AddHandler(UIElement.MouseDownEvent,新RoutedEventHandler(AssociatedObject_MouseDown),true);
}
无效关联对象\u鼠标向下(对象发送方,路由目标)
{
按钮源=发送方为按钮;
if(source!=null&&source.ContextMenu!=null)
{
source.ContextMenu.PlacementTarget=source;
source.ContextMenu.Placement=PlacementMode.Bottom;
source.ContextMenu.IsOpen=!source.ContextMenu.IsOpen;
}
}
附加时受保护的覆盖无效()
{
base.OnDetaching();
RemoveHandler(UIElement.MousedowEvent,新RoutedEventHandler(AssociatedObject_MouseDown));
}
}
XAML:
它工作正常,但我有一个小问题-在第二次单击按钮时(上下文菜单仍然打开),菜单关闭并立即重新打开,但预期的行为是关闭菜单-source.ContextMenu.IsOpen=!source.ContextMenu.IsOpen代码>。因此,似乎在MoseDown on按钮启动之前,其他功能会关闭菜单。如何避免这种情况?试试以下方法:
void AssociatedObject_MouseDown(object sender, RoutedEventArgs e)
{
e.handled = true; // handle the event
Button source = sender as Button;
//rest of the code ...
}
祝你好运 我想我找到了一个解决方案:
<Button Content="Left ContextMenu test" IsHitTestVisible="{Binding ElementName=cm, Path=IsOpen, Mode=OneWay, Converter={StaticResource BoolInverter}}">
<i:Interaction.Behaviors>
<extensions:LeftClickContextMenuButtonBehavior />
</i:Interaction.Behaviors>
<Button.ContextMenu>
<ContextMenu x:Name="cm">
<MenuItem Header="Item A" />
<MenuItem Header="Item B" />
</ContextMenu>
</Button.ContextMenu>
</Button>
这样,当您第二次单击按钮时,不会单击,但上下文菜单将关闭,因为它失去焦点。我认为这不起作用。此问题与未处理的事件无关。谢谢,但它仍然不起作用-在按钮检查IshitteVisible的值之前,ContextMenu.IsOpen似乎已设置为False。我认为,父窗口处理MouseDown,关闭所有上下文菜单,然后将MouseDown事件路由到按钮,但当时上下文菜单已经关闭,所以ishitestvisible=true和tegrefore按钮处理MouseDown并重新打开菜单……我在一个小测试应用程序中尝试了这段代码,效果很好。你能试一下这个例子吗?
<Button Content="Left ContextMenu test" IsHitTestVisible="{Binding ElementName=cm, Path=IsOpen, Mode=OneWay, Converter={StaticResource BoolInverter}}">
<i:Interaction.Behaviors>
<extensions:LeftClickContextMenuButtonBehavior />
</i:Interaction.Behaviors>
<Button.ContextMenu>
<ContextMenu x:Name="cm">
<MenuItem Header="Item A" />
<MenuItem Header="Item B" />
</ContextMenu>
</Button.ContextMenu>
</Button>
public class BoolInverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
if (value is bool)
return !(bool)value;
return value;
}
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
throw new NotImplementedException();
}
}