Comments (1)
pezy
commented on June 12, 2024
QWheelEvent::delta () 正是该问题的答案。
该函数返回滚轮滚过的一个距离，正好是滚轮旋转角度的8倍。正值表示往上滚动，负值表示往下滚动。
一般鼠标普遍以15度为一步，这种情况下，delta 的返回值是120 (8*15) 的整数倍。(120 units * 1/8 = 15 degrees.)
然而，对于一些高分辨率的鼠标来说，delta值可能是小于 120 的(小于15度)。 要支持这种可能性， 你要么让delta的值自加至120后作为一次滚动， 要么就每滚动一下就响应一次wheelEvent事件。
文档示例：
void MyWidget::wheelEvent(QWheelEvent *event)
{
int numDegrees = event->delta() / 8;
int numSteps = numDegrees / 15;
if (event->orientation() == Qt::Horizontal) {
scrollHorizontally(numSteps);
} else {
scrollVertically(numSteps);
}
event->accept();
}from qtlab.
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from qtlab.