Question

I’m wanting to know if there’s a way I can transform my view to look something like iPhone folders. In other words, I want my view to split somewhere in the middle and reveal a view underneath it. Is this possible?

EDIT:
Per the suggestion below, I could take a screenshot of my application by doing this:

UIGraphicsBeginImageContext(self.view.bounds.size);
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

Not sure what to do with this, however.

EDIT:2
I’ve figured out how to add some shadows to my view, and here’s what I’ve achieved (cropped to show relevant part):

EDIT:3

http://github.com/jwilling/JWFolders

Answer 1

the basic thought will be to take a picture of your current state and split it somewhere. Then animate both parts by setting a new frame. I don’t know how to take a screenshot programmatically so I can’t provide sample code…

EDIT: hey hey it’s not looking great but it works ^^

// wouldn't be sharp on retina displays, instead use "withOptions" and set scale to 0.0
// UIGraphicsBeginImageContext(self.view.bounds.size);
UIGraphicsBeginImageContextWithOptions(self.view.bounds.size, NO, 0.0);
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *f = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

CGRect fstRect = CGRectMake(0, 0, 320, 200);
CGRect sndRect = CGRectMake(0, 200, 320, 260); // was 0,200,320,280


CGImageRef fImageRef = CGImageCreateWithImageInRect([f CGImage], fstRect);
UIImage *fCroppedImage = [UIImage imageWithCGImage:fImageRef];
CGImageRelease(fImageRef);

CGImageRef sImageRef = CGImageCreateWithImageInRect([f CGImage], sndRect);
UIImage *sCroppedImage = [UIImage imageWithCGImage:sImageRef];
CGImageRelease(sImageRef);


UIImageView *first = [[UIImageView alloc]initWithFrame:fstRect];
first.image = fCroppedImage;
//first.contentMode = UIViewContentModeTop;
UIImageView *second = [[UIImageView alloc]initWithFrame:sndRect];
second.image = sCroppedImage;
//second.contentMode = UIViewContentModeBottom;

UIView *blank = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 320, 460)];
blank.backgroundColor = [UIColor darkGrayColor];

[self.view addSubview:blank];
[self.view addSubview:first];
[self.view addSubview:second];

[UIView animateWithDuration:2.0 animations:^{
    second.center = CGPointMake(second.center.x, second.center.y+75);
}];

You can uncomment the two .contentMode lines and the quality will improve but in my case the subview has an offset of 10px or so (you can see it by setting a background color to both subviews)

//EDIT 2: ok found that bug. Had used the whole 320×480 screen, but had to cut off the status bar so it should be 320×460 and all is working great 😉