The contextmenu provide event Collapse, but it seems do not work.

I can write the eventhandler for it, but the code respond to this event can not be executed no matter which operation is processed.

Is it a bug ?

{

.....................

ContextMenu buttonMenu = new ContextMenu(menuItems);
buttonMenu.Show(button1, new Point(0, button1 .Height ) );

buttonMenu.Collapse += new EventHandler(buttonMenu_Collapse);

}

void buttonMenu_Collapse(object sender, EventArgs e)
{

//no chance to see it
throw new Exception("The method or operation is not implemented.");
}

PJ. van de Sande wrote:

The ContextMenu variable is out of scope when the method exits. So the event will never be executed.

Thank you very much.

But it does not work even I use the contextmenu as a member variable.

------------------------------------------

private ContextMenu m_cmMenu;

{
InitializeComponent();

......

m_cmMenu = new ContextMenu();
m_cmMenu.Collapse += new EventHandler(m_cmMenu_Collapse);

}

void m_cmMenu_Collapse(object sender, EventArgs e)
{
//throw new Exception("The method or operation is not implemented.");
}

PJ. van de Sande wrote:

But now you only create a ContextMenu, you need to bind it to a control also or call the Show method yourself: // Bind menu to a control lstMyListView.ContextMenu = m_cmMenu; // Show it programaticly m_cmMenu.Show( _myControl, MousePosition );

Thanks.

Yes, I do.

I'm writing a dropdownbutton. It look like a button, it will popup a menu when you click it.

Most of task complete successful, such as add menu item, show menu. but there is a trouble ---- how to know when the menu Collapse?

Below is a simple sample code. It can show menu, but can not fire the event Collapse .

--------------------------------------------------------------------

public partial class Form1 : Form
{

ContextMenu buttonMenu;

public Form1()
{
InitializeComponent();
}

private void button1_Click(object sender, EventArgs e)
{
//Declare the menu items and the shortcut menu.
MenuItem menu1 = new MenuItem("Some Button Info");

MenuItem menu2 = new MenuItem("Some Other Button Info");

MenuItem[] menuItems = new MenuItem[] { menu1, menu2, new MenuItem("Exit") };

ContextMenu buttonMenu = new ContextMenu(menuItems);
buttonMenu.Show(button1, new Point(0, button1.Height));

buttonMenu.Collapse += new EventHandler(buttonMenu_Collapse);
}

void buttonMenu_Collapse(object sender, EventArgs e)
{
throw new Exception("The method or operation is not implemented.");
}

}

PJ. van de Sande wrote:

You wire the event after you show the menu, then it isn't triggerd. And when button1 is clicked and the menu is shown, the method exits and the menu is out of scope and will never be there again. So first wire the event and then show the menu.

................................

Thanks.

It seems that the half of your suggestion is right.

When I wire the event popup before show the menu, this event does work.

But the Collapse still do not work.

buttonMenu.Popup += new EventHandler(buttonMenu_Popup);
buttonMenu.Collapse += new EventHandler(buttonMenu_Collapse);

buttonMenu.Show(button1, new Point(0, button1.Height - 2));

}

void buttonMenu_Popup(object sender, EventArgs e)
{
MessageBox.Show("Popup");
}

void buttonMenu_Collapse(object sender, EventArgs e)
{
MessageBox.Show("Collapse");
}