如何检查触摸点是否在UIBezierPath(iOS)上

Question

我怎么知道触摸点(touchesBegan)是否在隐藏的UIBezierPath上？

Answer 1

[bezierPath containsPoint:touchPoint];

只需确保您的触摸点与bezierPaths点在同一坐标系中,并且这些点位于相同的上下文中,即在屏幕空间中.

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [touches anyObject];
    CGPoint touchPoint = [touch locationInView:self.view];
    if ([self.bezierPath containsPoint:touchPoint])
    {
        // do stuff
    }
}

另请注意:如果您在某些CoreGraphics绘图中使用UIBezierPath,则需要在touchPoint上翻转y轴,例如...

touchPoint.y = self.view.bounds.size.height - touchPoint.y;