我正在将一个MFC应用程序移植到.NET WinForms。在MFC应用程序中,您可以右键单击菜单或上下文菜单项,然后显示另一个包含诊断和配置项的上下文菜单。我试图将此功能移植到.NET,但我遇到了麻烦。
我已经能够捕获右键单击,禁用单击底层菜单并在正确的位置弹出上下文菜单,但原始菜单一丢失焦点就会消失。
在MFC中,我们通过使用 TPM_RECURSE 标记调用 TrackPopupMenuEx 来显示新的上下文菜单。
.NET中的ContextMenu 和较新的 ContextMenuStrip 类只有 Show 方法。有谁知道如何在.NET中执行此操作?
修改
我尝试通过p / invoke使用 TrackPopupMenuEx ,但这限制了您使用ContextMenu而不是在我们的应用程序中看起来不合适的ContextMenuStrip。它仍然无法正常工作。它不适用于新的 MenuStrip 和 ContextMenuStrip 。
我还尝试了子类化ToolStripMenuItem以查看是否可以向其添加上下文菜单。这适用于 MenuStrip ,但 ContextMenuStrip 仍允许右键单击事件作为点击进行传递。
答案 0 :(得分:10)
编辑,由于评论:
在:
protected override void OnClick(EventArgs e)
{
if (SecondaryContextMenu == null || MouseButtons != MouseButtons.Right)
{
base.OnClick(e);
}
}
这部分
MouseButtons != MouseButtons.Right
应该并且确实编译,因为它是对Control.MouseButtons的调用。由于Form继承了Control类,因此直接调用MouseButtons属性就足够了。
希望这会有所帮助:
public partial class Form1 : Form
{
class CustomToolStripMenuItem : ToolStripMenuItem
{
private ContextMenuStrip secondaryContextMenu;
public ContextMenuStrip SecondaryContextMenu
{
get
{
return secondaryContextMenu;
}
set
{
secondaryContextMenu = value;
}
}
public CustomToolStripMenuItem(string text)
: base(text)
{ }
protected override void Dispose(bool disposing)
{
if (disposing)
{
if (secondaryContextMenu != null)
{
secondaryContextMenu.Dispose();
secondaryContextMenu = null;
}
}
base.Dispose(disposing);
}
protected override void OnClick(EventArgs e)
{
if (SecondaryContextMenu == null || MouseButtons != MouseButtons.Right)
{
base.OnClick(e);
}
}
}
class CustomContextMenuStrip : ContextMenuStrip
{
private bool secondaryContextMenuActive = false;
private ContextMenuStrip lastShownSecondaryContextMenu = null;
protected override void Dispose(bool disposing)
{
if (disposing)
{
if (lastShownSecondaryContextMenu != null)
{
lastShownSecondaryContextMenu.Close();
lastShownSecondaryContextMenu = null;
}
}
base.Dispose(disposing);
}
protected override void OnControlAdded(ControlEventArgs e)
{
e.Control.MouseClick += new MouseEventHandler(Control_MouseClick);
base.OnControlAdded(e);
}
protected override void OnControlRemoved(ControlEventArgs e)
{
e.Control.MouseClick -= new MouseEventHandler(Control_MouseClick);
base.OnControlRemoved(e);
}
private void Control_MouseClick(object sender, MouseEventArgs e)
{
ShowSecondaryContextMenu(e);
}
protected override void OnMouseClick(MouseEventArgs e)
{
ShowSecondaryContextMenu(e);
base.OnMouseClick(e);
}
private bool ShowSecondaryContextMenu(MouseEventArgs e)
{
CustomToolStripMenuItem ctsm = this.GetItemAt(e.Location) as CustomToolStripMenuItem;
if (ctsm == null || ctsm.SecondaryContextMenu == null || e.Button != MouseButtons.Right)
{
return false;
}
lastShownSecondaryContextMenu = ctsm.SecondaryContextMenu;
secondaryContextMenuActive = true;
ctsm.SecondaryContextMenu.Closed += new ToolStripDropDownClosedEventHandler(SecondaryContextMenu_Closed);
ctsm.SecondaryContextMenu.Show(Cursor.Position);
return true;
}
void SecondaryContextMenu_Closed(object sender, ToolStripDropDownClosedEventArgs e)
{
((ContextMenuStrip)sender).Closed -= new ToolStripDropDownClosedEventHandler(SecondaryContextMenu_Closed);
lastShownSecondaryContextMenu = null;
secondaryContextMenuActive = false;
Focus();
}
protected override void OnClosing(ToolStripDropDownClosingEventArgs e)
{
if (secondaryContextMenuActive)
{
e.Cancel = true;
}
base.OnClosing(e);
}
}
public Form1()
{
InitializeComponent();
CustomToolStripMenuItem itemPrimary1 = new CustomToolStripMenuItem("item primary 1");
itemPrimary1.SecondaryContextMenu = new ContextMenuStrip();
itemPrimary1.SecondaryContextMenu.Items.AddRange(new ToolStripMenuItem[] {
new ToolStripMenuItem("item primary 1.1"),
new ToolStripMenuItem("item primary 1.2"),
});
CustomToolStripMenuItem itemPrimary2 = new CustomToolStripMenuItem("item primary 2");
itemPrimary2.DropDownItems.Add("item primary 2, sub 1");
itemPrimary2.DropDownItems.Add("item primary 2, sub 2");
itemPrimary2.SecondaryContextMenu = new ContextMenuStrip();
itemPrimary2.SecondaryContextMenu.Items.AddRange(new ToolStripMenuItem[] {
new ToolStripMenuItem("item primary 2.1"),
new ToolStripMenuItem("item primary 2.2"),
});
CustomContextMenuStrip primaryContextMenu = new CustomContextMenuStrip();
primaryContextMenu.Items.AddRange(new ToolStripItem[]{
itemPrimary1,
itemPrimary2
});
this.ContextMenuStrip = primaryContextMenu;
}
}
答案 1 :(得分:2)
你可能需要p / invoke方法。
[DllImport("user32.dll")]
static extern bool TrackPopupMenuEx(IntPtr hmenu, uint fuFlags, int x, int y,
IntPtr hwnd, IntPtr lptpm);
const int TPM_RECURSE = 0x0001;
答案 2 :(得分:0)
这显示了如何使用多个ContextMenus以及任何鼠标点击组合的不同ContextMenus。