QSplitter show a divider or a margin between the two widgets

Question

I have a QSplitter and two widgets on either side, but I want to be able to have a margin, so that there is a clear transition between the two widgets. I looked in QSplitter and

Answer 1

Here's how you can overwrite the QSplitter class to make the splitters to have some icon to let user know they can resize the widgets, See the image for output. enter image description here

from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
import sys

class Handle(QWidget):
    def paintEvent(self, e=None):
        painter = QPainter(self)
        painter.setPen(Qt.NoPen)
        painter.setBrush(Qt.Dense6Pattern)
        painter.drawRect(self.rect())

class customSplitter(QSplitter):
    def addWidget(self, wdg):
        super().addWidget(wdg)
        self.width = self.handleWidth()
        l_handle = Handle()
        l_handle.setMaximumSize(self.width*2, self.width*10)
        layout = QHBoxLayout(self.handle(self.count()-1))
        layout.setSpacing(0)
        layout.setContentsMargins(0,0,0,0)
        layout.addWidget(l_handle)

class Window(QMainWindow):
    def setUI(self, MainWindow):
        self.splt_v = customSplitter(Qt.Vertical)
        self.splt_v.setHandleWidth(8)
        self.splt_v.addWidget(QGroupBox("Box 1"))
        self.splt_v.addWidget(QGroupBox("Box 2"))
        self.splt_v.addWidget(QGroupBox("Box 3"))

        self.wdg = QWidget()
        self.v_lt = QVBoxLayout(self.wdg)
        self.v_lt.addWidget(self.splt_v)

        self.spl_h = customSplitter()
        self.spl_h.addWidget(self.wdg)
        self.spl_h.addWidget(QGroupBox("Box 4"))
        self.spl_h.addWidget(QGroupBox("Box 5"))

        self.h_lt = QHBoxLayout()
        self.h_lt.addWidget(self.spl_h)
        self.w = QWidget()
        self.w.setLayout(self.h_lt)
        self.w.setGeometry(0,0,1280,720)
        self.w.show()

if __name__ == '__main__':
    app = QApplication(sys.argv)
    MainWindow = QMainWindow()
    ui = Window()
    ui.setUI(MainWindow)
    sys.exit(app.exec_())