[FIXED] Unable to dynamically reset the maximum height of widgets in a QSplitter

Issue

I'd like to have a QSplitterHandle resize only the widget above it, by:

1. Initially fixing the maximum and minimum height of all the widgets (QFrame's actually) in the QSplitter.
2. On QSplitterHandle::mousePressEvent "increase the" the maximum height, and on QSplitterHandle::mouseReleaseEvent reset the maximum height to the current.

Code

#! /usr/bin/python

import sys
from PySide import QtGui
from PySide import QtCore

# Custom Splitter Handle
class SplitterHandle(QtGui.QSplitterHandle):
   QWIDGET_MAX_HEIGHT = 1000

   def __init__(self, index , orientation, parent):
      super(SplitterHandle , self).__init__(orientation, parent)
      self.index = index

   def getWidget( self ):
      return self.splitter().widget( self.index )

   # Remove height restriction on corresponding widget when dragging starts
  def mousePressEvent(self ,event ):
     widget = self.getWidget()
     widget.setMinimumHeight( 100 ) # FIX
     widget.setMaximumHeight( self.QWIDGET_MAX_HEIGHT )
     return QtGui.QSplitterHandle.mousePressEvent(self,event)

  # Freeze height of corresponding widget after dragging has ends
  def mouseReleaseEvent(self ,event ):
     widget = self.getWidget()
     widget.setMinimumHeight( widget.height() ) # FIX
     widget.setMaximumHeight( widget.height() )
     return QtGui.QSplitterHandle.mousePressEvent(self,event)

# Custom Splitter
class Splitter(QtGui.QSplitter):
   def __init__( self , orientation , parent = None):
      super(Splitter , self).__init__(orientation,parent)
      self.orientation = orientation

   def createHandle( self):
      return SplitterHandle( self.count() , self.orientation , self )      


class Example(QtGui.QWidget):
   def __init__(self):
      super(Example, self).__init__()
      hbox = QtGui.QVBoxLayout(self)

      frame1 = QtGui.QFrame()
      frame1.setFrameShape(QtGui.QFrame.StyledPanel)
      frame1.setMinimumHeight( 100 )
      frame1.setMaximumHeight( 100 )
      frame1.setStyleSheet("background-color: red;");

      frame2 = QtGui.QFrame()
      frame2.setFrameShape(QtGui.QFrame.StyledPanel)
      frame2.setMinimumHeight( 100 ) 
      frame2.setMaximumHeight( 100 )
      frame2.setStyleSheet("background-color: green;");

      frame3 = QtGui.QFrame()
      frame3.setFrameShape(QtGui.QFrame.StyledPanel)
      frame3.setMinimumHeight( 100 ) 
      frame3.setMaximumHeight( 100 )
      frame3.setStyleSheet("background-color: blue;");

      frame4 = QtGui.QFrame()
      frame4.setFrameShape(QtGui.QFrame.StyledPanel)
      frame4.setMinimumHeight( 100 ) 
      frame4.setMaximumHeight( 100 )
      frame4.setStyleSheet("background-color: yellow;");

      # The "absorber"
      frame5 = QtGui.QFrame()
      frame5.setStyleSheet("background-color: white;");

      ########################

      splitter = Splitter(QtCore.Qt.Vertical)

      splitter.addWidget(frame1)
      splitter.addWidget(frame2)
      splitter.addWidget(frame3)
      splitter.addWidget(frame4)
      splitter.addWidget(frame5)

      splitter.setChildrenCollapsible( False )
      hbox.addWidget(splitter)  

      self.setGeometry(300, 300, 300, 600)
      self.setWindowTitle('--Splitter--')
      self.show()

def main():
   app = QtGui.QApplication(sys.argv)
   ex = Example()
   sys.exit(app.exec_())

if __name__ == '__main__':
   main()

See application screenshot. The problem is that the attempts to dynamically reset the widget heights fail.

Solution

The problem is that you are applying the maximum size to an incorrect widget caused because you are passing an inappropriate index. The solution is to pass it self.count()-1:

def createHandle( self):
    return SplitterHandle(self.count()-1, self.orientation , self)  

Answered By - eyllanesc