python - 更新从其他函数创建的paintEvent对象的颜色

Question

我在paintEvent函数中使用QPainter创建了一个矩形。以下是我的代码

def paintEvent(self, event):
    QWidget.paintEvent(self, event)
    painter = QPainter(self)
    pen = QtGui.QPen(QtCore.Qt.black, 2, QtCore.Qt.SolidLine)

    painter.setPen(QtCore.Qt.red)
    painter.setBrush(QtGui.QColor(200, 0, 0))
    rect = QRect(1450,325,380,498)
    painter.drawRect(rect)
    painter.setFont(QtGui.QFont('Consolas', 30))
    painter.setPen(QtGui.QColor(0, 0, 0))
    painter.drawText(QRect(1450,325,380,498), QtCore.Qt.AlignCenter, str("Welcome"))

如何从其他函数更新矩形和文本内容(矩形内)的颜色？

def updateRectanle(conditon):
    if condition: 
        update_rectangle_color
        update_rectangle_text

Answer 1

正如您所知，您不应该直接调用 paintEvent()，您应该做的是告诉 GUI 您需要重新绘制，我们可以使用方法 repaint() 和 update()。第一种方法需要同步更新，对于第二种异步的情况，我更喜欢第二种情况。

def __init__(self, foo_params):
    super(Foo_class, self).__init__(super_foo_params)
    self._text = "Welcome"
    self._rect_color = QtGui.QColor(200, 0, 0)

def paintEvent(self, event):
    super(Foo_class, self).paintEvent(event)
    painter = QPainter(self)
    pen = QtGui.QPen(QtCore.Qt.black, 2, QtCore.Qt.SolidLine)

    painter.setPen(QtCore.Qt.red)
    painter.setBrush(self._rect_color)
    rect = QRect(1450,325,380,498)
    painter.drawRect(rect)
    painter.setFont(QtGui.QFont('Consolas', 30))
    painter.setPen(QtGui.QColor(0, 0, 0))
    painter.drawText(QRect(1450,325,380,498), QtCore.Qt.AlignCenter, self._text)

def updateRectanle(conditon):
    if condition: 
        self._rect_color = new_color
        self._text = new_text
        self.update()