上下文菜单项必须单击两次才能消失

Question

我正在列表视图上创建一个上下文菜单，以便能够对特定项目执行功能。右键单击时，上下文菜单正常显示，部分功能执行但不完全，上下文菜单再次显示。

我试图在表单的加载功能中移动上下文菜单创建和绑定，但似乎不起作用...

private JsonReport _lastItemTag;

public Form1()
{
    InitializeComponent();
}

private void ReportTemplateManager_Load(object sender, EventArgs e)
{
    // Initialize context menu for template control
    ContextMenu cm = new ContextMenu();
    cm.MenuItems.Add("Load", new EventHandler(LoadReport_Click));
    template_listview.ContextMenu = cm;
}

private void Template_listview_MouseClick(object sender, MouseEventArgs e)
{
    bool match = false;
    if (e.Button == MouseButtons.Right)
    {
        foreach (ListViewItem item in template_listview.Items)
        {
            if (item.Bounds.Contains(new Point(e.X, e.Y)))
            {
                template_listview.ContextMenu.Show(template_listview, new Point(e.X, e.Y));
                match = true;
                _lastItemTag = item.Tag as JsonReport;
                break;
            }
        }
        if (!match)
            _lastItemTag = null;
    }
}

下面的函数被执行，但没有关闭表单，我必须再次单击它才能关闭上下文菜单和表单本身...

private void LoadReport_Click(object sender, EventArgs e)
{
    if (_lastItemTag != null)
    {
        Console.WriteLine("Loading"); // This get executed
        _lastItemTag = null;
        this.Close(); // This doesnt close the form on the first time
    }
}

我不明白为什么LoadReport 函数可以“部分”执行而不关闭表单。

Answer 1

您似乎显示了两次菜单。

通过将上下文菜单分配给ContextMenu 属性，当您右键单击列表视图时，菜单将自动打开。无需手动显示菜单。

此外，无需遍历菜单项来查找匹配项。我什至不确定您要通过处理列表视图的MouseClick 事件来做什么。我认为你可以完全消除这种方法。

菜单项事件处理程序的sender 参数包含被单击的菜单项。您可以直接投射它并从那里获取 Tag 属性：

private JsonReport _lastItemTag;

public Form1()
{
    InitializeComponent();
}

private void ReportTemplateManager_Load(object sender, EventArgs e)
{
    // Initialize context menu for template control
    ContextMenu cm = new ContextMenu();

    //The event handler will be called when this menu item is clicked.
    cm.MenuItems.Add("Load", new EventHandler(LoadReport_Click));

    template_listview.ContextMenu = cm;
}

private void LoadReport_Click(object sender, EventArgs e)
{
    //The 'sender' argument is the menu item that was clicked
    //In this case, it is the Load menu item so cast the sender
    var menuItem = sender as MenuItem;

    //Now get the Tag property and cast it to JsonReport
    _lastItemTag = menuItem.Tag as JsonReport;

    if (_lastItemTag != null)
    {
        Console.WriteLine("Loading"); // This get executed
        this.Close(); // This doesnt close the form on the first time
    }
}