Anyway to animate UIImageView's contentMode from aspectFill to aspectFit?

Question

[UIView animateWithDuration:30.0f delay:0.0f options:UIViewAnimationOptionCurveEaseInOut animations:^{
    v.contentMode = UIViewContentModeScaleAspectFit;
    v.frame = v.superview.bounds;
} completion:^(BOOL finished) {
    [v removeFromSuperview];
}];

I want a UIImageView to resize and change the contentMode, but the code above doesn't work. It changed the contentMode immediately at the beginning of the animation.

Is there any way to animate it?

Sholes

Answer 1

UIImageView inherits its contentMode property from UIView. It is not one of the properties you can animate. More information can be found in the View Programming Guide.

Corinecorinna

thank you , i realized that it cannot be done by using uiimageview , so i just want find a eazy way to do that :) – Sholes

Animating the frame is probably your best bet, then. – Corinecorinna

i need to hide it under a view & pre-calc the position to reach the goal :) – Sholes

That sounds like a different question to me. – Corinecorinna

Answer 2

As others have mentioned there is no way to animate contentMode.

This library exists to solve that though! https://github.com/patrickbdev/PBImageView

imageView.contentMode = .scaleAspectFit

UIView.animateWithDuration(1) {
    self.imageView.contentMode = .scaleAspectFill
}

Summersault

Worked wonderfully with a complex UIViewController animated transition. Thanks! – Donetsk

Answer 3

Based on "What Can Be Animated", you cannot animate contentmode directly. However, you can try to animate the frame in order to get the same behavior as contentmode does. Once animation completed, you can set contentmode and frame back to original.

Alongshore

i think i can only set the imageview as a subview, then calculate the position & size munually, then animate it – Sholes

Answer 4

To achieve that, you can use this component on github : https://github.com/VivienCormier/UIImageViewModeScaleAspect

Slumber

Answer 5

yes contentMode can NOT be animated but "center" can be - use that for contentMode animation emulation in situations where frame or bounds animation doesn't fit the bill

Semblance

Answer 6

Since iOS 4.0, I think, you can animate the transition with UIView.transition(...) as described in this post. In Swift 5 it looks like this:

let contentMode: UIView.ContentMode = imageView.contentMode == .scaleAspectFit ? .scaleAspectFill : .scaleAspectFit
UIView.transition(with: imageView, duration: 0.5,
                  options: .transitionFlipFromBottom,
                  animations: {
                    self.imageView.contentMode = contentMode
                  },
                  completion: nil)

Philender

Answer 7

MishieMoo is correct. contentMode can NOT be animated. I think you can just change the bounds of the view to achieve what you want.

Tso

Answer 8

I think your need this: https://github.com/vitoziv/VICMAImageView

You can use VICMAImageView like a UIImageView, and animate contentMode in your animation block:

[UIView animateWithDuration:0.3
                 animations:^{
                     imageView.contentMode = UIViewContentModeScaleAspectFill;
                 }];

Acidosis