Enable Tablet press-and-hold gesture in MFC applications

  • Article

This article provides information about how to enable press-and-hold gesture in a Microsoft Foundation Class (MFC) application.

Original product version:   Visual Studio 2010 and later versions
Original KB number:   2846829

Summary

On a Tablet PC running Windows, the system will send a WM_TABLET_QUERYSYSTEMGESTURESTATUS message to active windows that could receive user input. In an MFC application, all windows are typically derived from the CWnd class, and this base class handles this message in its OnTabletQuerySystemGestureStatus method. This method calls the virtual function CWnd::GetGestureStatus, which will then return TABLET_DISABLE_PRESSANDHOLD, for performance reasons. If your application wants to enable the press-and-hold gesture, you must override this method in your derived window class and return something that doesn't include the TABLET_DISABLE_PRESSANDHOLD flag.

Default behavior: Disable press and hold gesture

To enable the right-click concept that usually means display the context menu, and comes in the form of WM_RBUTTONDOWN, WM_RBUTTONUP, and WM_CONTEXTMENU messages and ISG_HOLDENTER and ISG_RIGHTTAP events, the press and hold gesture must be enabled for that window. In order to detect this gesture, by necessity some delay is introduced to distinguish between a simple press (treated as a left-click) and a press and hold (right-click). Thus, it will take longer for left click events to be raised, and the application will seem less responsive. So, for this reason, the default behavior is to disable the press and hold gesture.

Enable Tablet press-and-hold gesture

If your MFC application needs this gesture to implement right-click handling, you must override the virtual GetGestureStatus function for any derived window classes that need to implement a right-click handler. Let's assume that it is a view class named CMyView defined in MyView.h, and implemented in MyView.cpp. In MyView.h, add the following:

virtual ULONG GetGestureStatus(CPoint ptTouch);

In MyView.cpp, add the following:

ULONG CMyView::GetGestureStatus(CPoint /*ptTouch*/)
{
    return 0;
}

The return value 0 could be replaced by a combination of other flags as described in the WM_TABLET_QUERYSYSTEMGESTURESTATUS documentation, but if you wish to enable press and hold, don't include the TABLET_DISABLE_PRESSANDHOLD flag.