Hi,
Currently i'm developing this scripted plasmoid(python):
http://kde-look.org/content/show.php/On ... ent=116413.

I'm trying to add gradient effect to the top and bottom of listview,
something like krunner's query result, by porting krunner's resultview codes.

After i added the codes for gradient, my plasmoid always crash.

Below my paintevent codes:

Code: Select all

    def paintEvent(self,event):
        #taken from krunner's result view, all credit go to it's developers :)

        backBuffer = QPixmap(self.viewport().size())
        backBuffer.fill(Qt.transparent)
        backBufferPainter = QPainter(backBuffer)

        painter = QPainter(self.viewport())
        painter.setRedirected(self.viewport(),backBuffer)
        QListView.paintEvent(self,event)
        painter.restoreRedirected(self.viewport())

        gradientHeight = 48
        if (self.topFadeout.isNull() or self.topFadeout.width() != self.width()):
            g = QLinearGradient(0, 0, 0, gradientHeight)
            g.setColorAt(1, Qt.white )
            g.setColorAt(0, Qt.transparent )
            self.topFadeout = QPixmap(self.width(), gradientHeight)
            self.topFadeout.fill(Qt.transparent)
            p = QPainter(self.topFadeout)
            p.setCompositionMode(QPainter.CompositionMode_Source)
            p.fillRect(self.topFadeout.rect(), g)
       
        if (self.bottomFadeout.isNull() or self.bottomFadeout.width() != self.width()):
            g = QLinearGradient(0, 0, 0, gradientHeight)
            g.setColorAt(0, Qt.white )
            g.setColorAt(1, Qt.transparent )
            self.bottomFadeout = QPixmap(self.width(), gradientHeight)
            self.bottomFadeout.fill(Qt.transparent)
            p = QPainter(self.bottomFadeout)
            p.setCompositionMode(QPainter.CompositionMode_Source)
            p.fillRect(self.bottomFadeout.rect(), g)
       
        backBufferPainter.setCompositionMode(QPainter.CompositionMode_DestinationIn)
       
        backBufferPainter.drawPixmap(QPoint(0,0), self.topFadeout)       
        backBufferPainter.drawPixmap(QPoint(0,self.height()-self.bottomFadeout.height()), self.bottomFadeout)

        painter.drawPixmap(event.rect(), backBuffer, event.rect())



I tried to comment all paintevent codes starting from this: backBufferPainter = QPainter(backBuffer), my plasmoid didnot crash.

Any hints to solve this problem?

Thanks,
Reza

Does it occur if you only comment the following lines?

Code: Select all

        painter = QPainter(self.viewport())
        painter.setRedirected(self.viewport(),backBuffer)
        QListView.paintEvent(self,event)
        painter.restoreRedirected(self.viewport())

If so, try renaming it something that may not already be used such as itemPainter...

i changed this line:

Code: Select all

  backBufferPainter = QPainter(backBuffer)


to:

Code: Select all

   backBufferPainter = QPainter()
   backBufferPainter.begin(backBuffer)


i think somehow the problem is solved:).