的iOS zoomToRect具有持续时间
问题描述:
可能重复:
Any way of changing the duration of zoomToRect for UIScrollView?的iOS zoomToRect具有持续时间
是否有任何方式来复制的行为[UIScrollView的zoomToRect:zoomRect动画:YES],使得动画持续了给定时间?
答
你可以把这个在您的UIScrollView
子类:
- (void)zoomToRect:(CGRect)rect animated:(BOOL)animated
{
[UIView animateWithDuration:(animated?0.3f:0.0f)
delay:0
options:UIViewAnimationOptionBeginFromCurrentState
animations:^{
[super zoomToRect:rect animated:NO];
}
completion:nil];
}
答
如何使用:
[UIView beginAnimations:@"" context:nil];
[UIView setAnimationDuration:2.0]; //Or any other duration
[theScroll setContentOffset:offsetPoint]; //offsetPoint is a CGPoint that defines the point you want your scroller to show
[UIView commitAnimations];
的缺点是,你需要计算精确CGPoint达到你想要得到正确的偏移量。
+0
这个我试过的形式给出,还必须设置缩放级别和生成的动画不等同于zoomToRect。 – silviupop
答
我设法使用一些CA3DTransforms来实现zoomToRect。如果有人感兴趣,我会在这里粘贴代码。
我不得不保留一个引用scrollView的原始框架,以使其工作。
rect.origin.x = ((int)rect.origin.x) % (int)self.initialFrame.size.width;
float scale = MIN(self.initialFrame.size.width/rect.size.width,self.initialFrame.size.height/rect.size.height);
CGSize scaledFrameSize = CGSizeMake(self.initialFrame.size.width/scale, self.initialFrame.size.height/scale);
CGPoint middleOfFrame = CGPointMake(self.initialFrame.size.width/2 ,self.initialFrame.size.height/2);
CGPoint transformPoint = CGPointMake(rect.origin.x + scaledFrameSize.width/2,rect.origin.y + scaledFrameSize.height/2);
CGPoint offsetToCenter = CGPointMake((scaledFrameSize.width - rect.size.width)/2 * scale,(scaledFrameSize.height - rect.size.height)/ 2 * scale);
[UIView animateWithDuration:1 animations:^ {
self.layer.transform = CATransform3DConcat(CATransform3DConcat(CATransform3DConcat(CATransform3DMakeTranslation(middleOfFrame.x,middleOfFrame.y, 0),
CATransform3DMakeTranslation(-transformPoint.x, -transformPoint.y,0)),
CATransform3DMakeScale(scale, scale, 1)),
CATransform3DMakeTranslation(offsetToCenter.x, offsetToCenter.y, 0));
}];
这太棒了。 – silviupop