/// <summary>
/// Private helper to raise a ShowContextMenu event.
/// </summary>
/// <param name="eventKey">The event key of the event to raise.</param>
/// <param name="e">A ShowContextMenuEventArgs that contains the event data.</param>
private void RaiseEvent(object eventKey, ShowContextMenuEventArgs e)
{
ShowContextMenuEventHandler showContextEventHandler = (ShowContextMenuEventHandler)Events[eventKey];
if (showContextEventHandler != null)
showContextEventHandler(this, e);
}
/// <summary>
/// Raises the ShowContextMenu event.
/// </summary>
/// <param name="e">A ShowContextMenuEventArgs that contains the event data.</param>
internal void RaiseShowContextMenu(ShowContextMenuEventArgs e)
{
OnShowContextMenu(e);
}
/// <summary>
/// Raises the ShowContextMenu event.
/// </summary>
/// <param name="e">A ShowContextMenuEventArgs that contains the event data.</param>
protected virtual void OnShowContextMenu(ShowContextMenuEventArgs e)
{
RaiseEvent(ShowContextMenuEventKey, e);
}
/// <summary>
/// Processes Windows messages.
/// </summary>
/// <param name="m">The Windows Message to process.</param>
protected override void WndProc(ref Message m)
{
// Dispatch the message.
switch (m.Msg)
{
// The WM_CONTEXTMENU message notifies a window that the user clicked the right
// mouse button (right clicked) in the window (or performed some other action that
// will display the context menu).
case (int)WM.CONTEXTMENU:
{
// Crack out x and y position. This is in screen coordinates.
int x = MessageHelper.LOWORDToInt32(m.LParam);
int y = MessageHelper.HIWORDToInt32(m.LParam);
// Remember the old ContextMenu so we can restore it later on should we change
// it below.
ContextMenu oldContextMenu = ContextMenu;
// Raise the ShowContextMenu event.
ShowContextMenuEventArgs showContextMenuEventArgs;
if (x == -1 && y == -1)
{
// The position is -1, -1. This indicates that the context menu is being
// shown without a mouse position. Raise the ShowContextMenu event on
// this control.
showContextMenuEventArgs = new ShowContextMenuEventArgs(x, y, ContextMenu);
OnShowContextMenu(showContextMenuEventArgs);
}
else
{
// The position is not -1, -1. This indicates that the context menu is
// being shown via a mouse gesture. Attempt to locate the lightweight
// control at the position.
Point point = PointToClient(new Point(x, y));
LightweightControl lightweightControl = GetMouseLightweightControlAtClientPoint(point);
// If the lightweight control is non-null, and has a ContextMenu, raise
// the ShowContextMenu event on it.
if (lightweightControl != null)
{
// Instantiate the ShowContextMenuEventArgs.
showContextMenuEventArgs = new ShowContextMenuEventArgs(x, y, lightweightControl.ContextMenu);
// Raise the ShowContextMenu event.
lightweightControl.RaiseShowContextMenu(showContextMenuEventArgs);
}
else
{
// Raise the ShowContextMenu event.
showContextMenuEventArgs = new ShowContextMenuEventArgs(x, y, ContextMenu);
OnShowContextMenu(showContextMenuEventArgs);
}
}
// If the event was not handled, handle it.
if (!showContextMenuEventArgs.Handled)
{
// If we have a context menu to show, show it. Otherwise, pass the message
// on to the base class.
if (showContextMenuEventArgs.ContextMenu != null)
{
// Make the context menu we're showing the context menu of this
// control. Doing so allows mnemonic processing to work.
ContextMenu = showContextMenuEventArgs.ContextMenu;
// Show the context menu.
showContextMenuEventArgs.ContextMenu.Show(this, new Point(showContextMenuEventArgs.X, showContextMenuEventArgs.Y));
}
else
base.WndProc(ref m);
}
// If we changed the context menu of this control, restore it.
if (ContextMenu != oldContextMenu)
ContextMenu = oldContextMenu;
// Done!
return;
}
case (int)WM.SETFOCUS:
{
if (_focusAndAccessibilityController != null && ActiveControl == null)
{
//eat focus messages so we can override all focus handling for this control!
OnGotFocus(EventArgs.Empty);
return;
}
break;
}
}
// Call the base class's method.
try
{
base.WndProc(ref m);
}
catch (Exception e)
{
Trace.Fail("LightweightControlContainerControl WndProc Exception", e.ToString());
}
}
