python中label函數_python-如何在QLabel中使用QPainter

documentation建議在paintEvent中使用QPainter.

通過使用下面的構造函數,在paintEvent方法内部,無需調用begin()和end()

(您的Labella類隻是缺少用于初始化父級的參數)

方法save()和restore()可以友善地存儲QPainter的标準配置,進而允許在還原設定之前繪制一些不同的内容.

import sys

from PyQt5.QtWidgets import *

from PyQt5.QtGui import QPainter, QColor, QBrush

class Labella(QLabel):

def __init__(self, parent):

super().__init__(parent=parent)

self.setStyleSheet('QFrame {background-color:grey;}')

self.resize(200, 200)

def paintEvent(self, e):

qp = QPainter(self)

self.drawRectangles(qp)

qp.setBrush(QColor(200, 0, 0))

qp.drawRect(0,0,20,20)

def drawRectangles(self, qp):

qp.setBrush(QColor(255, 0, 0, 100))

qp.save() # save the QPainter config

qp.drawRect(10, 15, 20, 20)

qp.setBrush(QColor(0, 0, 255, 100))

qp.drawRect(50, 15, 20, 20)

qp.restore() # restore the QPainter config

qp.drawRect(100, 15, 20, 20)

class Example(QWidget):

def __init__(self):

super().__init__()

lb = Labella(self)

self.setGeometry(300, 300, 350, 300)

self.setWindowTitle('Colours')

self.show()

if __name__ == '__main__':

app = QApplication(sys.argv)

ex = Example()

sys.exit(app.exec_())