styleditem_mwe.py

#!/usr/bin/env python3

import sys
from PyQt5.QtWidgets import QApplication, QMainWindow, QGraphicsView, QGraphicsScene, QGraphicsItem, QGraphicsTextItem
from PyQt5.QtGui import QPainterPath

class StyledItem(QGraphicsTextItem):
	def __init__(self, parent=None):
		super().__init__(parent)
		# Items can be moved and selected
		self.setFlag(QGraphicsItem.ItemIsMovable)
		self.setFlag(QGraphicsItem.ItemIsSelectable)

	def boundingRect(self):
		m = 10 # Margin
		br = super().boundingRect()
		abr = br.adjusted(-m, -m, m, m)
		return abr

	def shape(self):
		ss = QPainterPath()
		ss.addRect(self.boundingRect())
		return ss

	def paint(self, painter, options, widget=None):
		# Draw a rectangle around the text
		br = self.boundingRect()
		painter.drawRect(br)
		# Draw the text
		super().paint(painter, options, widget)

class MainWindow(QMainWindow):
	def __init__(self):
		super().__init__()
		# Setup scene and view
		self._scene = QGraphicsScene()
		self._view = QGraphicsView(self)
		self._view.setScene(self._scene)
		self._view.setDragMode(QGraphicsView.RubberBandDrag)
		self.setCentralWidget(self._view)

		self._i = StyledItem()
		# self._i.setPlainText('foo') ### UNCOMMENT ###
		self._scene.addItem(self._i)
	
if __name__ == '__main__':
	app = QApplication(sys.argv)
	mw = MainWindow()
	mw.setWindowTitle('Example')
	mw.show()

	sys.exit(app.exec_())