如何使 QWidget 圆角

Question

我想知道是否有办法使 Qt 小部件的角变圆？

from PyQt4 import QtCore, QtGui

class Custom(QtGui.QWidget):
    def __init__(self, *args, **kwargs):
        QtGui.QWidget.__init__(self, *args, **kwargs)
        self.setWindowOpacity(0.9)
        self.setWindowFlags(QtCore.Qt.Popup|QtCore.Qt.FramelessWindowHint)
        self.setWindowTitle('Custom')
        self.resize(440,220)
        self.move(QtGui.QCursor.pos())

    def closeEvent(self, event):
        event.accept()
        sys.exit(app.exec_())

    def mousePressEvent(self, event):
        self.close() 

if __name__ == "__main__":
    app = QtGui.QApplication(sys.argv)
    w = Custom()
    w.show()
    sys.exit(app.exec_())

Answer 1

您可以使用QWidget.setMask(self, QRegion) 。

C ++中的一个例子：

QWidget *widget = new QWidget;
widget->resize(300, 200);

const int radius = 10;

QPainterPath path;
path.addRoundedRect(widget->rect(), radius, radius);
QRegion mask = QRegion(path.toFillPolygon().toPolygon());
widget->setMask(mask);

widget->show();

Answer 2

解：

以下是hank使用C ++概述的Python解决方案：

import sys
from PySide import QtCore, QtGui

class Custom(QtGui.QWidget):
    def __init__(self, *args, **kwargs):
        QtGui.QWidget.__init__(self, *args, **kwargs)
        self.setWindowOpacity(0.9)
        self.setWindowFlags(QtCore.Qt.Popup|QtCore.Qt.FramelessWindowHint)
        self.setWindowTitle('Custom')

        radius = 40.0
        path = QtGui.QPainterPath()
        self.resize(440,220)
        path.addRoundedRect(QtCore.QRectF(self.rect()), radius, radius)
        mask = QtGui.QRegion(path.toFillPolygon().toPolygon())
        self.setMask(mask)
        self.move(QtGui.QCursor.pos())

    def closeEvent(self, event):
        event.accept()
        sys.exit(app.exec_())

    def mousePressEvent(self, event):
        self.close() 

if __name__ == "__main__":
    app = QtGui.QApplication(sys.argv)
    w = Custom()
    w.show()
    sys.exit(app.exec_())

Answer 3

如果您的小部件是 static，它会起作用，但是如果您想调整它的大小并且仍然有圆角，则需要覆盖该方法，它看起来像这样：

void Widget::paintEvent(QPaintEvent *event)
{
    const int radius = 7;

    QPainterPath path;
    path.addRoundedRect(rect(), radius, radius);
    QRegion mask = QRegion(path.toFillPolygon().toPolygon());
    setMask(mask);

    QWidget::paintEvent(event);
}