Question

我在Hyperlink中有Grid。我将命令绑定到启用/禁用它的超链接。然后我使用命令禁用它。然后在其父（Grid）上设置IsEnabled=False属性。之后，我使用我的命令启用我的超链接并启用网格，但超链接不会激活！

以下是样本：

Command testCommand = new Command();

public MainWindow() {
  InitializeComponent();
  hl.Command = testCommand;
}

private void Start(object sender, RoutedEventArgs e) {

  //Disable Hyperlink
  testCommand.Enabled = false;
  //Disable Grid
  grid.IsEnabled = false;
  //Enable Hyperlink
  testCommand.Enabled = true;
  //Enable Grid
  grid.IsEnabled = true;
  //hl.IsEnabled = true; //if uncomment this all will be work
}

XAML：

<Window x:Class="WpfApplication25.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow"
        Height="172"
        Width="165">
  <StackPanel>
    <Grid x:Name="grid">
      <TextBlock>
        <Hyperlink x:Name="hl">Test</Hyperlink>
      </TextBlock>
    </Grid>
    <Button Content="Start"
            Name="button1"
            Click="Start" />
  </StackPanel>
</Window>

注册ICommand：

public class Command : ICommand {
  private bool enabled;
  public bool Enabled {
    get {
      return enabled;
    }
    set {
      enabled = value;
      if (CanExecuteChanged != null)
        CanExecuteChanged(this, EventArgs.Empty);
    }
  }
  public bool CanExecute(object parameter) {
    return Enabled;
  }
  public event EventHandler CanExecuteChanged;
  public void Execute(object parameter) { }
}

更新

如果将Hyperlink替换为Button，即使其父级被禁用，它也会被启用（grid.IsEnabled = false）。

Answer 1

哇，我明白了这是你缺少的东西

 public class Command : ICommand
    {
        private bool enabled;
        public bool Enabled
        {
            get
            {
                return enabled;
            }
            set
            {
                enabled = value;
                //if (CanExecuteChanged != null)
                //    CanExecuteChanged(this, EventArgs.Empty);
            }
        }

        public bool CanExecute(object parameter)
        {
            return Enabled;
        }
        public event EventHandler CanExecuteChanged
        {
            add { CommandManager.RequerySuggested += value; }
            remove { CommandManager.RequerySuggested -= value; }
        }

        public void Execute(object parameter) { }
    }

CanExecuteChanged将命令订阅委派给CommandManager

超链接无法与关联命令一起正常工作

1 个答案: