get Gestures in QWindow

Xv1nX

I have a program with Qmainwindow as root. In Qmainwindow I created a MainWidget inherited from Qwidget, which acts like my layout. This MainWidget contains a Qwindow, where I draw opengl directly. Now I want that my Qwindow get gestures event, if I run my program on a window tablet.
Would I get gestures event in my MainWidget and can manually tell my Qwindow?
If not, can I create a transparent qwidget over my Qwindow and get gestures events?
Thanks in advance

SGaist

Hi,

IIRC if you want to handle gesture in widgets you should take a look at this chapter of Qt's documentation.

Hope it helps

Xv1nX

@SGaist
Thanks for your reply, but i am not sure how to get gesture events to my QWindow, since QWindow is not support QGesture.

SGaist

Why about using your main window as a "proxy" to your QWindow ?

Xv1nX

@SGaist
i tried but the Qmainwindow doesn't get the GestureEvents if i do it over the QWindow. I can confirm that QmainWindow does receive GestureEvent, if i perform gesture on another window like a QDockWindow, which also has Qmainwindow as parent.
Any suggestion is appreciated. Thanks

SGaist

By the way, why not use QOpenGLWidget rather than QWindow since you are using widgets anyway ?

Xv1nX

@SGaist
I used all possibilities: QGLWidget, QOpenGLWidget, QOpenGLWindow and manually Qwindow+QOpenGlContext. The latter is much smoother and lightweight than others. I also have to use Qwindow.

Another Question:
How do I get WM_GESTURE in nativeEvent? All I get are WM_Touch events.
There is no QNativeGestureEvent, too.

Do you have any advices regarding following ideas:

use a Qwidget in a new window and make it transparent. Overlap this window with over my application to get gesture.
detect all needed gestures my myself from touch events
try to get messages in WinPrc (my app is only for Windows).

Which way is the better one?
Thanks in advance

SGaist

What's WinPrc ?

For your ideas, what should your application do ?

Xv1nX

@SGaist
i am thinking about monitoring windows message by myself to filter wm_gesture.
something like this:
https://ic3man5.wordpress.com/2012/04/29/monitoring-microsoft-windows-messages-using-qt-4-8/

The development guideline for Touch Gesture on msdn.microsoft.com said, one can only get either WM_Touch or WM_Gesture. And it seems QT always get the WM_Touch events. I may have to unregister the app for getting touch events.

My app is a ported programm from old win32. it contains a main are, where i draw OpenGL on a QWindow by myself. now it should get multitouch features to manipulate the content.

Xv1nX

I found out the solution using native Windows Gestures WM_Gesture.
By default QT registers QMainWindow-Window as a Touch Window, so the QMainWindow-App only get WM_Touch events.
As said above one can only get either WM_Touch event or WM_Gesture event. So you have to unregister the window from getting Touch event. I do that in the constructor like this:

HWND myHwnd = reinterpret_cast<HWND>(this->winId());
PULONG flag = 0;
bool istouch = IsTouchWindow(myHwnd,flag);
if(istouch)
	UnregisterTouchWindow(myHwnd);

now i get WM_Gesture events in nativeEvent:

   	bool OpenGLWindow::nativeEvent(const QByteArray & eventType, void* message, long* result)
{
	MSG* msg = reinterpret_cast<MSG*>(message);
	switch(msg->message){
	case WM_GESTURE:
	case WM_GESTURENOTIFY:
		emit sendNativeEvent(eventType, message, result);
		break;
	}
	return false;
}

Thanks for your help.