如何处理 QPainter 的边界矩形点击

Question

Now I draw my custom widget by using QPainterPath and rotate technique, code snippet is listed here:

QRectF flowerBanRect(-radius + (-width / 2), -radius + (-margin) + (-height), width, height);
QPainterPath flowerPath;
flowerPath.moveTo(-radius + (-width / 4), -diameter + (-margin));
flowerPath.lineTo(-radius + width / 4, -diameter + (-margin));
flowerPath.lineTo(-radius + width / 2, -diameter + (-margin) + (-height));
flowerPath.lineTo(-radius + (-width / 2), -diameter + (-margin) + (-height));

QPainterPath diffPath = flowerPath - headPath;

painter->setBrush(QBrush(getReagentSeatColor(0)));
painter->fillPath(diffPath, QBrush(getReagentSeatColor(0)));
painter->drawText(flowerBanRect, Qt::AlignHCenter | Qt::AlignTop, QString("01"));
painter->save();

float degree = 360.0 / MAX_TRAY;
for (int i = 0; i < MAX_TRAY - 1; ++i) {
    painter->rotate(degree);
    painter->setBrush(QBrush(getReagentSeatColor(i + 1)));
    painter->fillPath(diffPath, QBrush(getReagentSeatColor(i + 1)));
    painter->drawText(flowerBanRect, Qt::AlignHCenter | Qt::AlignTop, QString("%1").arg(i + 2, 2, 10, QChar('0')));
}

But now how I handle the EVERY SECTOR clicking.

Answer 1

The best approach would be to override the mousePressEvent of the QWidget in your class like this.

void mousePressEvent(QMouseEvent *event) override;

Then you call whatever function you want to get the position from the QMouseEvent doc, but I would recommend event->pos() because it returns the position relative to the widget you are calling it from. You can either calculate the positions of each sector at run time, or you can store them in a QList or QMap. Then compare the positions and figure out which sector the mouse is in.