WPF MouseOver MenuItem 阻止焦点返回到窗口

Question

我有一个带有自定义菜单和一些按钮的窗口。当用户将鼠标放在菜单项上时，我使菜单自动展开。每个按钮都有“鼠标悬停”状态。我的问题是，当我将鼠标悬停在菜单上打开菜单后，按钮不再显示“鼠标悬停”状态。

这是我的窗口的简化版本：

<Window>
    <Button Cursor="Hand" Width="20" Height="20">
        <Button.Style>
            <Style TargetType="{x:Type Button}">
                <Setter Property="Background" Value="White" />
                <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="{x:Type Button}">
                        <Border x:Name="Border" Background="{TemplateBinding Background}" CornerRadius="30">
                            <Image Source="../Icons/close.png" Width="9" Height="9" />
                        </Border>
                    </ControlTemplate>
                </Setter.Value>
                </Setter>
            <Style.Triggers>
                <Trigger Property="IsMouseOver" Value="True">
                    <Setter Property="Background" Value="Gray" />
                </Trigger>
            </Style.Triggers>
            </Style>
        </Button.Style>
    </Button>

    <ScrollViewer>
        <Menu ItemsSource="{Binding Path=CommandMenuItems}">
            <Menu.ItemContainerStyle>
                <Style TargetType="{x:Type MenuItem}">
                    <Setter Property="Focusable" Value="False"/>
                    <Setter Property="Template">
                        <Setter.Value>
                        <ControlTemplate TargetType="{x:Type MenuItem}">
                                             <Border>
                                                 <Grid>
                                                     <ContentPresenter />
                                                     <TextBlock />
                                                     <Grid />
                                                     <Popup IsOpen={Binding IsSubmenuOpen}"/>
                                                 </Grid>
                                             </Border>
                                <ControlTemplate.Triggers>
                                    <MultiTrigger>
                                        <MultiTrigger.Conditions>
                                            <Condition Property="IsMouseOver" Value="True" />
                                            <Condition Property="Role" Value="SubmenuHeader" />
                                        </MultiTrigger.Conditions>
                                        <Setter Property="IsSubmenuOpen" Value="True" />
                                    </MultiTrigger>
                                    <MultiTrigger>
                                        <MultiTrigger.Conditions>
                                            <Condition Property="IsMouseOver" Value="True" />
                                            <Condition Property="Role" Value="TopLevelHeader" />
                                        </MultiTrigger.Conditions>
                                        <Setter Property="IsSubmenuOpen" Value="True" />
                                    </MultiTrigger>
                                        
                                </ControlTemplate.Triggers>

                            </ControlTemplate>
                            </Setter.Value>
                    </Setter>
            </Menu.ItemContainerStyle>
    </ScrollViewer>
</Window>

我尝试在弹出窗口关闭时手动将焦点设置回窗口，但没有成功。

Answer 1

我终于找到答案了！事实证明，当光标离开弹出窗口时，菜单并没有释放鼠标。

向弹出窗口添加处理程序：

<Popup Closed="PART_Popup_Closed">
    <!-- Popup contents here -->
</Popup>

并向处理程序添加：

private void PART_Popup_Closed(object sender, EventArgs e)
{
    if(CommandMenu.IsMouseCaptured)
        CommandMenu.ReleaseMouseCapture();
}

现在一切都很好。