小编ben*_*opp的帖子

我的窗口代码后面定义了一个依赖属性“Active”...

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

  public bool Active
  {
     get { return (bool) GetValue(ActiveProperty); }
     set { SetValue(ActiveProperty, value); }
  }
  public static readonly DependencyProperty ActiveProperty =
      DependencyProperty.Register("Active", typeof(bool), typeof(MainWindow), new UIPropertyMetadata(false));
}

然后我使用 xaml 中的两个复选框绑定到该属性。我还想根据该属性更改矩形的填充。我怎样才能做到这一点？

<Window x:Class="WpfTest.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow"
        Height="350"
        Width="525"
        DataContext="{Binding RelativeSource={RelativeSource Self}}">
  <StackPanel>
    <CheckBox IsChecked="{Binding Active}" />
    <CheckBox IsChecked="{Binding Active}" />
    <Rectangle Fill="Gray"
               Width="50"
               Height="50">
      <Rectangle.Style>
        <Style TargetType="Rectangle">
          <Style.Triggers>
            <DataTrigger Binding="{Binding Active}"
                         Value="True">
              <Setter Property="Fill"
                      Value="Green" />
            </DataTrigger> …

我有一个带有Button和ListBox的窗口.

  <Window x:Class="ListBoxFail.MainWindow"
          xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
          xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
          Height="350" Width="525">
     <Grid>
        <Popup Name="Popup" StaysOpen="False">
           <Rectangle Fill="Blue" Width="100" Height="100"/>
        </Popup>
        <Button Content="ClickMe" Click="OpenPopup" VerticalAlignment="Top"/>
        <ListBox SelectionChanged="OpenPopup" VerticalAlignment="Bottom">
           <ListBoxItem Content="One"/>
           <ListBoxItem Content="Two"/>
        </ListBox>
     </Grid>
  </Window>

Button和ListBox都会触发Popup打开:

  namespace ListBoxFail {
     partial class MainWindow {
        public MainWindow() { InitializeComponent(); }
        private void OpenPopup(object a, object b) { Popup.IsOpen = true; }
     }
  }

单击该按钮时,将打开弹出窗口.单击其他任何位置然后按预期关闭弹出窗口.

单击ListBox时,将打开弹出窗口.但是,此时关闭弹出窗口的唯一方法是让主窗口失去焦点.单击窗口或单击按钮不会关闭弹出窗口.

是什么赋予了？为什么ListBox忽略了StaysOpen = false指令？我究竟做错了什么？

在我的应用程序中,我有一个颜色资源.我有一个元素使用该颜色作为xaml中的动态资源.

  <Window x:Class="ResourcePlay.MainWindow"
          xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
          xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
          Title="MainWindow" Height="350" Width="425">
     <Window.Resources>
        <Color x:Key="MyColor">Red</Color>
     </Window.Resources>
     <Grid>
        <Rectangle VerticalAlignment="Top" Width="80" Height="80" Margin="10">
           <Rectangle.Fill>
              <SolidColorBrush x:Name="TopBrush" Color="{DynamicResource MyColor}"/>
           </Rectangle.Fill>
        </Rectangle>
        <Rectangle VerticalAlignment="Bottom" Width="80" Height="80" Margin="10">
           <Rectangle.Fill>
              <SolidColorBrush x:Name="BottomBrush"/>
           </Rectangle.Fill>
        </Rectangle>
     </Grid>
  </Window>

在代码中,我想复制此资源引用.

  using System.Windows;
  using System.Windows.Media;

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

           // I want to copy the resource reference, not the color.
           BottomBrush.Color = TopBrush.Color;

           // I'd really rather do something like this.
           var reference …