I have a button with a default command and a context menu for other available commands:

<Button Content="Do this" Height="23" Width="75" Command="local:MyCommands.ThisCommand">
    <Button.ContextMenu>
        <ContextMenu>
            <MenuItem Header="Do this" Command="local:MyCommands.ThisCommand" />
            <MenuItem Header="Do that" Command="local:MyCommands.ThatCommand" />
        </ContextMenu>
    </Button.ContextMenu>
</Button>

在默认情况下，在出现的右键菜单开始在光标的热点：

By default, the context menu appears starting at the hot spot of the cursor:

不过，我希望它出现在一个固定的相对位置，按钮（假的，编辑截图）下：

However, I'd like it to appear at a fixed relative position, beneath the button (fake, edited screenshot):

设置上下文菜单中的展示位置， PlacementRectangle 和 PlacementTarget 性质似乎并没有做任何事情;上下文菜单中坚持挂光标，无论我用鼠标右键单击我的按钮。更糟的是，聚焦按钮，击中菜单键使上下文菜单坐在按钮前，完全阻止它。

Setting the context menu's Placement, PlacementRectangle and PlacementTarget properties doesn't seem to do anything; the context menu insists on hanging off the cursor wherever I right-click my button. Worse, focusing the button and hitting the menu key causes the context menu to sit in front of the button, blocking it completely.

那么，究竟如何我指定的上下文菜单中应该出现在按钮下方？

So, how exactly do I specify that the context menu should appear beneath the button?

推荐答案

查看下ContextMenu.Placement

和尝试这种

<Button Content="Do this" Height="23" Width="75" 
     ContextMenuService.Placement="Bottom"
     Command="local:MyCommands.ThisCommand">
    <Button.ContextMenu>
        <ContextMenu>
            <MenuItem Header="Do this" Command="local:MyCommands.ThisCommand" />
            <MenuItem Header="Do that" Command="local:MyCommands.ThatCommand" />
        </ContextMenu>
    </Button.ContextMenu>
</Button>