添加到Deactivate事件后C#窗体状态恢复方法失效求助

我的应用包含主窗体与Overlay窗体：Overlay可通过调整尺寸最小化至屏幕顶部，主窗体可最小化到任务栏或系统托盘。点击Overlay上的按钮可切换其显示状态，同时主窗体会切换为FormWindowState.Normal。我希望该逻辑不仅在点击按钮时触发，还能在Overlay失去焦点时触发，但将恢复主窗体状态的OnHideOverlay调用加入Deactivate事件关联的OverlayNoFocus方法后，所有场景下该恢复逻辑均失效。

Overlay窗体代码 #

public event System.EventHandler OnShowOverlay;
public event System.EventHandler OnHideOverlay;

private void ShowOverlay()
{
    OnShowOverlay(this, null);
    this.Focus();
    OverlayPanel.Visible = true;
    this.Height = 70;
    this.InfoPanel.Location = new Point(25, 35);
    this.OverlayShowButton.Location = new Point(0, 35);
}
private void HideOverlay()
{
    if(OnHideOverlay != null)
    {
        OnHideOverlay(this, null); //!!! 当将该调用加入OverlayNoFocus时，问题出现
        this.Focus(); 
        this.OverlayPanel.Visible = false; //*** 只要OnHideOverlay不在OverlayNoFocus中，这些代码均可正常运行
        this.OverlayShowButton.Location = new Point(0, 0); //***
        this.InfoPanel.Location = new Point(25, 0); //***
        this.Height = 35; //***
    }
}
private void OverlayShowButton_Click(object sender, MouseEventArgs e)
{
    OverlayPanel.Visible = !OverlayPanel.Visible;
    if (OverlayPanel.Visible)
    {
        ShowOverlay();
    }
    else
    {
        HideOverlay();
    }
}

public void OverlayNoFocus(object sender, EventArgs e)
{
    HideOverlay(); //!!!
}

Overlay窗体设计器代码 #

this.Deactivate += new System.EventHandler(OverlayNoFocus);

主窗体代码 #

public MainForm()
{
    //无关代码

    this.overlay.OnShowOverlay += new System.EventHandler(onOverlayShow);
    this.overlay.OnHideOverlay += new System.EventHandler(onOverlayHide);
    this.overlay.Show();

    //无关代码
}

FormWindowState saveWinState = new FormWindowState();
        
void onOverlayShow(object sender, EventArgs e)
{
    saveWinState = this.WindowState;
    this.Show();
    this.WindowState = FormWindowState.Normal;
}
void onOverlayHide(object sender, EventArgs e)
{
    this.WindowState = saveWinState;
}

核心问题 #

1. 循环触发事件：当Deactivate事件触发HideOverlay时，OnHideOverlay会让主窗体恢复状态并获得焦点，这又会触发Overlay的Deactivate事件，形成无限循环，导致状态恢复逻辑失效。
2. 强制焦点干扰：HideOverlay中的this.Focus()会强制Overlay重新获取焦点，进一步打乱正常的焦点流转，加剧循环问题。

修复步骤 #

1. 移除强制焦点代码
   删除HideOverlay中的this.Focus()调用，避免干扰正常焦点切换：

   private void HideOverlay()
   {
       if(OnHideOverlay != null)
       {
           OnHideOverlay(this, null);
           // 移除this.Focus();
           this.OverlayPanel.Visible = false;
           this.OverlayShowButton.Location = new Point(0, 0);
           this.InfoPanel.Location = new Point(25, 0);
           this.Height = 35;
       }
   }
   

2. 添加状态判断避免重复执行
   在HideOverlay和OverlayNoFocus中增加状态判断，仅当Overlay处于展开状态时才执行隐藏逻辑：

   private void HideOverlay()
   {
       if(OnHideOverlay != null && OverlayPanel.Visible)
       {
           OnHideOverlay(this, null);
           this.OverlayPanel.Visible = false;
           this.OverlayShowButton.Location = new Point(0, 0);
           this.InfoPanel.Location = new Point(25, 0);
           this.Height = 35;
       }
   }
   
   public void OverlayNoFocus(object sender, EventArgs e)
   {
       if (OverlayPanel.Visible)
       {
           HideOverlay();
       }
   }
   

3. 优化主窗体状态保存逻辑
   仅当主窗体非正常状态时才保存状态，避免无效赋值：

   void onOverlayShow(object sender, EventArgs e)
   {
       if (this.WindowState != FormWindowState.Normal)
       {
           saveWinState = this.WindowState;
       }
       this.Show();
       this.WindowState = FormWindowState.Normal;
   }
   

内容的提问来源于stack exchange，提问作者Jonas Alexander Offersen