1.
open class VericalCenteringScrollView: UIScrollView { override open var contentOffset: CGPoint { didSet { let contentSize = self.contentSize let scrollViewSize = self.bounds.size var contentOffset = self.contentOffset if contentSize.height < scrollViewSize.height { contentOffset.y = -(scrollViewSize.height - contentSize.height) / 2.0; } super.contentOffset = contentOffset } } }
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+ (UIImage *)createLoadingImage:(UIColor *)color size:(CGSize)size centerImage:(UIImage *)image2 { /*生成loadingImage,中心为image2*/ UIGraphicsBeginImageContext(size); // Draw image1 // [image1 drawInRect:CGRectMake(0, 0, size.width, size.height)]; CGRect rect=CGRectMake(0.0f, 0.0f, size.width, size.height); CGContextRef context = UIGraphicsGetCurrentContext(); CGContextSetFillColorWithColor(context, [color CGColor]); CGContextFillRect(context, rect); // Draw image2 [image2 drawInRect:CGRectMake((size.width-image2.size.width)/2, (size.height-image2.size.height)/2, image2.size.width, image2.size.height)]; UIImage *resultingImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); return resultingImage; }