我的路由事件觸及子元素之前的根UI元素。這是預期的嗎?我怎樣才能讓路由事件首先碰到子元素?路由事件問題 - 在子元素之前觸擊根UI元素
目標:如果文本輸入比「自定義文本」之外的任何地方,把文中的「默認文本」
結果:Window_PreviewTextInput正在熱播custom_PreviewTextInput之前,即使我的光標焦點在「自定義文本框」
我應該改變什麼?
XAML
<Window x:Class="WpfApplication2.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" SizeToContent="WidthAndHeight"
PreviewTextInput="Window_PreviewTextInput"
>
<Grid Margin="100,100,100,100">
<StackPanel>
<StackPanel Orientation="Horizontal">
<TextBlock Text="default" Width="100"/>
<TextBox x:Name="defaultTB" Width="300" Height="50"/>
</StackPanel>
<StackPanel Orientation="Horizontal">
<TextBlock Text="custom" Width="100"/>
<TextBox x:Name="custom" PreviewTextInput="custom_PreviewTextInput" Width="300" Height="50"/>
</StackPanel>
</StackPanel>
</Grid>
</Window>
代碼背後:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
namespace WpfApplication2
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
//goal: if text is typed anywhere except custom textbox, put text in default textbox
private void Window_PreviewTextInput(object sender, TextCompositionEventArgs e)
{
Keyboard.Focus(defaultTB);
}
//goal: if text is typed in custom TB, put text there, and end the event routing
private void custom_PreviewTextInput(object sender, TextCompositionEventArgs e)
{
e.Handled = true;
}
}
}