CGRect到UIImage

Question

我有这样的代码：

CGRect visibleRect;
visibleRect.origin = mainViewController.scrollView.contentOffset;
visibleRect.size = mainViewController.scrollView.bounds.size;

我想将内容存储在UIImage中的visibleRect中。这有可能吗？

Answer 1

下面的代码可能会起作用：

UIGraphicsBeginImageContext(visibleRect.size);
CGContextTranslateCTM(UIGraphicsGetCurrentContext(), visibleRect.origin.x,
    visibleRect.origin.y);
[mainViewController.scrollView.layer 
    renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

Answer 2

您不能在CGRect中存储UIImage。您将执行类似于下面的操作

CGRect visibleRect;
visibleRect.origin = mainViewController.scrollView.contentOffset;
visibleRect.size = mainViewController.scrollView.bounds.size;

UIImageView* img = [[UIImageView alloc] init];
[img setFrame:visibleRect];
[img setImage:[UIImage imageNamed:@"Your-img"]];
[[self view] addSubview:img];
[img release];