Transparent Widgets not working

Goffer

Hello community,

I can't get my widgets to be transparent, always end up with a black or fading to black background
I'm on Gnome 2.28.2, I'm pretty sure it works on Windows though.

from PySide import QtGui, QtCore

widget = QtGui.QWidget()
widget.setAttribute(QtCore.Qt.WA_TranslucentBackground)
widget.show()

Any solution for that ?

Thx

mrjj

@Goffer
Hi
Can you try with
widget.setAttribute(Qt.WA_NoSystemBackground, True) also ?

I assume you mean fully transparent and not faded color/semi. ?

Goffer

Well, for the example sake we're trying fully transparent just to demonstrate that transparency doesn't work on some platforms.
But my goal is to have a semi-transparent window (that requires custom painting) that's why I said fading to black since opacity is replaced by black.

Even with the extra line it's still black, I've tested on Windows and it's black too ...

But if I do :

test_widget.setWindowOpacity(0.5)

it works on Windows but not on Gnome ... but that's not what I want anyway (This will affect the entire window not only the background)

I need a way to set opacity that is going to work on all platforms or at least the main ones.

Goffer

I have an other piece of code that represent exactly what I'm trying to do.

form PySide import QtGui, QtCore

class RoundWindow(QtGui.QWidget):
    def __init__(self):
        super(RoundWindow, self).__init__()
        self.initUI()

    def initUI(self):
        self.setWindowFlags(QtCore.Qt.FramelessWindowHint)
        self.setAttribute(QtCore.Qt.WA_TranslucentBackground)

    def sizeHint(self):
        return QtCore.QSize(300,300)

    def paintEvent(self, event):
        qp = QtGui.QPainter()
        qp.begin(self)
        qp.setRenderHint(QtGui.QPainter.Antialiasing);
        qp.setPen(QtCore.Qt.NoPen);
        qp.setBrush(QtGui.QColor(255, 0, 0, 127));
        qp.drawEllipse(0, 0, 300, 300);
        qp.end()


rw = RoundWindow()
rw.show()

This works perfectly on Windows, but no luck on Gnome, I have a black square with my red circle