leaveEvent on transparent area issue

[nooky59]

I don't know if this will work, but you can try see if you can use QDesktopWidget for taping to these event.
But my guess is that it will not work, since probably QDesktopWidget will be in global (not your application) scope.
But its worth a try.

Yes, it was my idea cause QDesktopWidget inherits from QWidget so there is the mouse events.

But as it is written in the Qt doc : Instead of using QDesktopWidget directly, use QApplication::desktop(). I don't think I can inherits my own DesktopWidget from QDesktopWidget, reimplement events and then construct it in my code without calling QApplication::desktop()...

But perhaps by digging with events filter and tryin' to intercept the QDesktopWidget events...

But I think I will stick with QRgba(0, 0, 0, 1) as I don't notice a difference between the overlayed areas and the pure areas of the desktop.

[high_flyer]

use QApplication::desktop()

That's what I meant.

[nooky59]

Ok, Rgba(0,0,0, 1) or whatever color with an alpha value of 1 is definitively a bad idea !

It could be noticed a little depending of the screen color and the viewing angle for a LCD screen.

Moreover, my co-worker who is the infographic artist told me that it could be far more noticeable on CRT screen with a particular contrast.

I will have to dig and I'll try with the QDesktopWidget

[nooky59]

Just for information, events filtering on the QDesktopWidget doesn't work so much :

In my constructor :

desktop = QApplication::desktop();
desktop->installEventFilter(this);
desktop->setMouseTracking(true);

desktop = QApplication::desktop();
desktop->installEventFilter(this);
desktop->setMouseTracking(true);

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And in the event :

bool MyWidget::eventFilter(QObject *target, QEvent *event)
{
	int tmp = -1;
	if(target == desktop)
	{
		tmp = event->type();
 
		switch(tmp)
		{
		case 109: // Mouse tracking state change
		case 74: // Should be Polished
		case 75: // Is Polished
			break;
 
		default:
			tmp = tmp;
			break;
		}
	}
 
	return false;
}

bool MyWidget::eventFilter(QObject *target, QEvent *event)
{
	int tmp = -1;
	if(target == desktop)
	{
		tmp = event->type();

		switch(tmp)
		{
		case 109: // Mouse tracking state change
		case 74: // Should be Polished
		case 75: // Is Polished
			break;

		default:
			tmp = tmp;
			break;
		}
	}
	
	return false;
}

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I've set a breakpoint on the tmp = tmp line in the default case.

I can only seen the third events from the switch / case (perhaps some others, I haven't tried everything but mouse moves and keypress didn't falled in the events filter.

But I've told you that QColor(0, 0, 0, 1) could be visible on a screen, even on an LCD depending of the way you look at it.

It seems that QColor(255, 255, 255, 1) is less visible, I can't see the semi-transparency, it appears really transparent.

The infographic artist told me that a 50% grey QColor(127, 127, 127, 1) is even more neutral.

Hope it could help. If someone has a CRT screen with a crazy contrast rate, just tell me if you see something on a single color desktop background ;o)