Question

如果您处理PreviewMouseDown的{{1}}事件且UserControl内部为UserControl，则不会触发内置本机检查事件，也不是点击事件（突出显示为蓝色）。如果您不处理预览事件，它可以正常工作。

我认为预览事件不会将事件标记为已处理，但即使使用

ToggleButton

之后将不会有点击或检查事件。

如何启用togglebutton的click and checked事件？

了解问题的代码：

WpfApplication1.cs

e.handled = false;

WpfApplication.Xaml

namespace WpfApplication1
{
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void UserControl1_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
        {
            //working
            MessageBox.Show("Preview down");
            e.Handled = false; //this is what I tried
        }

        private void UserControl1_PreviewMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
        {
            //working
            MessageBox.Show("preview up");
        }
    }
}

UserControl1.cs：

<Window x:Class="WpfApplication1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApplication1"
        mc:Ignorable="d"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <local:UserControl1 PreviewMouseLeftButtonDown="UserControl1_PreviewMouseLeftButtonDown" PreviewMouseLeftButtonUp="UserControl1_PreviewMouseLeftButtonUp" ></local:UserControl1>
    </Grid>
</Window>

UserControl1.xaml

namespace WpfApplication1
{
    public partial class UserControl1 : UserControl
    {
        public UserControl1()
        {
            InitializeComponent();
        }

        private void ToggleButton_Checked(object sender, RoutedEventArgs e)
        {
            //Not called
            MessageBox.Show("test");
        }

        private void ToggleButton_Click(object sender, RoutedEventArgs e)
        {
            //not called
            MessageBox.Show("test");
        }
    }
}

Answer 1

当触发用户控件中的事件时，您需要为用户控件引发事件处理程序。这将上升链并处理两者的均衡。

点击ToggleButton后，它会触发ToggleButton_Click并触发事件UserControl1_PreviousMouseLeftButtonDown。

WpfApplication1

UserControl1.ToggleButtonClick += new EventHandler(UserControl1_PreviewMouseLeftButtonDown);

private void UserControl1_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
    MessageBox.Show("Preview down");
    // Handle the event
}

的UserControl1

public event EventHandler ToggleButtonClick;

private void ToggleButton_Click(object sender, RoutedEventArgs e)
{
    MessageBox.Show("test");
    // Handle the event
}

在父控件中处理PreviewMouseDown-Event后，WPF Togglebutton不会切换

1 个答案:

WpfApplication1

的UserControl1