xcode masonry doesn't set the correct frame

Question

I'm on a project that is using masonry autolayout, and I'm having some issues with the animation, so the thing I have to do is to have a drawer that will appear from the top of the screen and will appear with an animation, so the content of the container view(it can be 1 view or multiple views) is been added using views with masonry, the issue that I have is that when I debug the views, the frame that I got is always Frame(0 0; 0 0) y since I need to apply animations I need the frame to capture the height of the container view, is there a way to have the correct frame or is it an specific way to work with animations and autolayout?

Answer 1

Try to capture the height of frame in viewDidLayoutSubviews for UIViewController or layoutSubviews for UIView.

To apply animation for AutoLayout, you have to reset the constraint like this:

// tell constraints they need updating
[self setNeedsUpdateConstraints];

// update constraints now so we can animate the change
[self updateConstraintsIfNeeded];

[UIView animateWithDuration:0.4 animations:^{
    [self layoutIfNeeded];
}];

and update or remake the constraints in updateConstraints.

See also: https://github.com/SnapKit/Masonry/blob/master/Examples/Masonry%20iOS%20Examples/MASExampleUpdateView.m