我在UIViewController中有一个UIScrollView。它启用了滚动和缩放功能。它包含一个UIImageView,当用户旋转设备时,想法是图像保持居中。问题是,当设备旋转时,它实际上显示在左侧而不是中心,它应该停留在那里。这是我正在使用的代码。当UIScrollView旋转时调用设置框架:
-(void)setFrame:(CGRect)frame {
float previousWidth = self.frame.size.width;
float newWidth = frame.size.width;
[super setFrame:frame];
self.imageView.center = CGPointMake(self.bounds.size.width / 2, self.bounds.size.height / 2);
[self setupScales];
self.zoomScale = self.zoomScale * (newWidth / previousWidth);
}
答案 0 :(得分:1)
我在uiscrollview的子类中使用以下layoutsubviews方法:
- (void)layoutSubviews {
[super layoutSubviews];
if ([[self subviews] count] == 0) {
return;
}
// center the image as it becomes smaller than the size of the screen
CGSize boundsSize = self.bounds.size;
CGRect frameToCenter = ((UIView*)[[self subviews] objectAtIndex:0]).frame;
// center horizontally
if (frameToCenter.size.width < boundsSize.width)
frameToCenter.origin.x = (boundsSize.width - frameToCenter.size.width) / 2;
else
frameToCenter.origin.x = 0;
// center vertically
if (frameToCenter.size.height < boundsSize.height)
frameToCenter.origin.y = ((boundsSize.height - frameToCenter.size.height) / 2);
else
frameToCenter.origin.y = 0;
((UIView*)[[self subviews] objectAtIndex:0]).frame = frameToCenter;
}
答案 1 :(得分:0)
您可能还需要设置滚动视图的contentOffset
属性
答案 2 :(得分:0)
如果scrollview通过方向更改调整大小,请尝试使用
self.imageView.autoresizingMask = UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin | UIViewAutoresizingFlexibleBottomMargin | UIViewAutoresizingFlexibleTopMargin;