c# - 如何从实现页面访问自定义控件中存在的按钮？

Question

我的 generic.xaml 包含以下代码:

<ControlTemplate TargetType="local:customVideoControl">

   <Grid>

          <Grid.RowDefinitions>
                     <RowDefinition Height="600"/>
                     <RowDefinition Height="200"/>
          </Grid.RowDefinitions>

           <Grid.ColumnDefinitions>
                       <ColumnDefinition Width="200"/>
                       <ColumnDefinition Width="200"/>
                       <ColumnDefinition Width="200"/>
            </Grid.ColumnDefinitions>

                    <MediaElement x:Name="customMediaPlayer" Source="{TemplateBinding CustomMediaSource}"
                                   HorizontalAlignment="Center"
                                   VerticalAlignment="Center"
                                   Height="{TemplateBinding Height}"
                                   Width="{TemplateBinding Width}"
                                  Grid.Row="0" Grid.ColumnSpan="3"
                                  />

                    <ToggleButton x:Name="playPauseBtn" Height="50" Width="50" Content="Pause" Grid.Row="1" Grid.Column="0"/>
                     <Button x:Name="prevBtn" Height="50" Width="50" Content="Prev" Grid.Row="1" Grid.Column="1"/>
                     <Button x:Name="nextBtn" Height="50" Width="50" Content="Next" Grid.Row="1" Grid.Column="2"/>

   </Grid>
</ControlTemplate>

现在在 applyTemplate 上，我正在访问如下控件:

 public override void OnApplyTemplate()
        {
            base.OnApplyTemplate();

            ToggleButton playPauseBtn = GetTemplateChild("playPauseBtn") as ToggleButton;

            Button prevBtn= GetTemplateChild("prevBtn") as Button;
            Button nextBtn = GetTemplateChild("nextBtn") as Button;
            MediaElement customMediaPlayer = GetTemplateChild("customMediaPlayer") as MediaElement;

            playPauseBtn.Checked += (obj, Args) =>
                {
                    customMediaPlayer.Pause();
                    playPauseBtn.Content = "Play";
                };

            playPauseBtn.Unchecked += (obj, Args) =>
                {
                    customMediaPlayer.Play();
                    playPauseBtn.Content = "Pause";
                };



            nextBtn.Click += (obj, Args) =>
                {
                    customMediaPlayer.Source=new Uri(CustomMediaSource.ToString(),UriKind.RelativeOrAbsolute);

                };

            prevBtn.Click += (obj, Args) =>
            {
                customMediaPlayer.Source = new Uri(CustomMediaSource.ToString(), UriKind.RelativeOrAbsolute);
            };

        }

现在我想在我正在实现的页面中访问 nextBtn

CustomVideoControl myVControl=new CustomVideoControl();

这将创建控件的实例，但我想在单击下一个和上一个按钮，thta 存在于 generic.xaml 中的 CustomVideoControl 中。任何帮助将不胜感激。

谢谢，子轩

Answer 1

您只需向您的控件添加几个事件。

 public event EventHandler MovedPrevious
 public event EventHandler MovedNext

现在这通常是这样实现的:-

 protected virtual void OnMovedPrevious(EventArgs e)
 {
   var handler = MovedPrevious;
   if (handler != null)
     handler(this, e);   
 }

 protected virtual void OnMovedNext(EventArgs e)
 {
   var handler = MovedNext;
   if (handler != null)
     handler(this, e);   
 }

现在在您现有的点击事件中:-

nextBtn.Click += (obj, Args) =>
{
  customMediaPlayer.Source=new Uri(CustomMediaSource.ToString(),UriKind.RelativeOrAbsolute);  //No idea what this doing
  OnMovedNext(EventArgs.Empty);
};

prevBtn.Click += (obj, Args) =>
{
  customMediaPlayer.Source = new Uri(CustomMediaSource.ToString(), UriKind.RelativeOrAbsolute); //No idea what this is doing either
  OnMovedPrevious(EventArgs.Empty);
};

现在在你的消费代码中你可以做这样的事情:-

CustomVideoControl myVControl=new CustomVideoControl();
myVControl.MovedNext += (s, args) => { /* deal with next */ };
myVControl.MovedPrevious += (s, args) => { /* deal with previous */ };