显示虚拟键盘时点击WebControl内的文本框

Question

我已经创建了一个虚拟键盘，弹出的wpf文本框控件的键盘。点击网页内的文本框时，如何让键盘弹出？

用于显示文本框的逻辑如下：

static void TouchScreenKeyboardPropertyChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e) 
     { 
      FrameworkElement host = sender as FrameworkElement; 
      if (host != null) 
      { 
       host.GotFocus += new RoutedEventHandler(OnGotFocus); 
       host.LostFocus += new RoutedEventHandler(OnLostFocus); 
      } 
     } 

    static void OnGotFocus(object sender, RoutedEventArgs e) 
    { 
     Control host = sender as Control; 

     if (sender == typeof(TextBox)) 
     { 
      _PreviousTextBoxBackgroundBrush = host.Background; 
      _PreviousTextBoxBorderBrush = host.BorderBrush; 
      _PreviousTextBoxBorderThickness = host.BorderThickness; 

      host.Background = Brushes.Yellow; 
      host.BorderBrush = Brushes.Red; 
      host.BorderThickness = new Thickness(4); 
     } 


     _CurrentControl = host; 

     if (_InstanceObject == null) 
     { 
      FrameworkElement ct = host; 
      while (true) 
      { 
       if (ct is Window) 
       { 
        ((Window)ct).LocationChanged += new EventHandler(TouchScreenKeyboard_LocationChanged); 
        ((Window)ct).Activated += new EventHandler(TouchScreenKeyboard_Activated); 
        ((Window)ct).Deactivated += new EventHandler(TouchScreenKeyboard_Deactivated); 
        break; 
       } 
       if(ct.Parent != null) 
       ct = (FrameworkElement)ct.Parent; 
      } 

      _InstanceObject = new TouchScreenKeyboard(); 
      _InstanceObject.AllowsTransparency = true; 
      _InstanceObject.WindowStyle = WindowStyle.None; 
      _InstanceObject.ShowInTaskbar = false; 
      _InstanceObject.ShowInTaskbar = false; 
      _InstanceObject.Topmost = true; 

      host.LayoutUpdated += new EventHandler(tb_LayoutUpdated); 
     } 
    } 

    static void TouchScreenKeyboard_Deactivated(object sender, EventArgs e) 
    { 
     if (_InstanceObject != null) 
     { 
      _InstanceObject.Topmost = false; 
     } 
    } 

    static void TouchScreenKeyboard_Activated(object sender, EventArgs e) 
    { 
     if (_InstanceObject != null) 
     { 
      _InstanceObject.Topmost = true; 
     } 
    } 

    static void TouchScreenKeyboard_LocationChanged(object sender, EventArgs e) 
    { 
     syncchild(); 
    } 

    static void tb_LayoutUpdated(object sender, EventArgs e) 
    { 
     syncchild(); 
    } 

    static void OnLostFocus(object sender, RoutedEventArgs e) 
    { 

     Control host = sender as Control; 
     host.Background = _PreviousTextBoxBackgroundBrush; 
     host.BorderBrush = _PreviousTextBoxBorderBrush; 
     host.BorderThickness = _PreviousTextBoxBorderThickness; 

     if (_InstanceObject != null) 
     { 
      _InstanceObject.Close(); 
      _InstanceObject = null; 
     } 
    } 

    #endregion 
} 

    private static void syncchild() 
    { 
     if (_CurrentControl != null && _InstanceObject != null) 
     { 

      Point virtualpoint = new Point(0, _CurrentControl.ActualHeight + 3); 
      Point Actualpoint = _CurrentControl.PointToScreen(virtualpoint); 

      if (WidthTouchKeyboard + Actualpoint.X > SystemParameters.VirtualScreenWidth) 
      { 
       double difference = WidthTouchKeyboard + Actualpoint.X - SystemParameters.VirtualScreenWidth; 
       _InstanceObject.Left = Actualpoint.X - difference; 
      } 
      else if (!(Actualpoint.X > 1)) 
      { 
       _InstanceObject.Left = 1; 
      } 
      else 
       _InstanceObject.Left = Actualpoint.X; 

      _InstanceObject.Top = Actualpoint.Y; 
      _InstanceObject.Show(); 
     } 
    } 

private static void SetKeyInBrowser(string key) 
    { 
     var elementName = (((mshtml.HTMLDocument)(dom)).activeElement).id; 

     if (elementName != null) 
     { 
      var existingText = dom.getElementById(elementName).getAttribute("value"); 
      if (existingText == null) 
      { 
       existingText = ""; 
      } 
      //if it's a backspace. 
      if (isBackspace) 
      { 
       existingText = existingText.ToString().Remove(existingText.ToString().Length - 1); 
       dom.getElementById(elementName).setAttribute("value", existingText.ToString()); 
      } 
      else if (key.Length != 0) 
      { 
       dom.getElementById(elementName).setAttribute("value", existingText.ToString() + key[key.Length - 1]); 
      } 
     } 
     isBackspace = false; 
    } 

Answer 1

您需要使用JavaScript为。你需要知道什么时候这个文本框是这样专注的： Check if focus is on a textfield

然后一旦焦点事件在JavaScript上被触发，你应该调用你的WPF函数来显示键盘了。这里有用的提示：

How to programmaticaly check if a text input box inside a web page loaded in WPF Browser has focus?