image->load(fileName);
// Scale the image to given size
*image = image->scaled(resultSize, Qt::KeepAspectRatio);
QImage fixedImage(resultSize, QImage::Format_ARGB32_Premultiplied);
QPainter painter(&fixedImage);
painter.setCompositionMode(QPainter::CompositionMode_Source);
painter.fillRect(fixedImage.rect(), Qt::transparent);
painter.setCompositionMode(QPainter::CompositionMode_SourceOver);
painter.drawImage(imagePos(*image), *image);
painter.end();
button->setIcon(QPixmap::fromImage(fixedImage));
*image = fixedImage;
这个没看明白呀,就是image载入一个存在的图片, fixedImage是对一个区域操作,也没图片实例;先ainter.setCompositionMode(QPainter::CompositionMode_Source);在painter.setCompositionMode(QPainter::CompositionMode_SourceOver);什么意思呀,最后在这个区域画图的时候还
QPoint ImageComposer::imagePos(const QImage &image) const
{
return QPoint((resultSize.width() - image.width()) / 2,
(resultSize.height() - image.height()) / 2);
}
是什么意思