如何使UIView扩展为包含具有自动布局和IB的UIImageView或UITextView？

Question

I have a UIView that contains two subviews - a UIImageView or a UITextView. The UIImageView has a fixed height and width. The UITextView has variable size.

Only one of the UIImageView and UITextView would be displayed at a time. I plan to accomplish this programmatically by setting hidden = YES .

I would like the UIView to hug whichever child view is not hidden with no margin.

I would like to accomplish this with IB and autolayout if possible because the rest of the view is built this way.

So far I have created constraints that link the 4 edges of both of the subviews to the parent view and constraints for the height and width of the UIImageView. Naturally this creates a content priority ambiguity.

I would appreciate any advice.

Thank you!

Answer 1

So the contain view has to have trailing constraint and constraint with bottom which should have IBOutlet(s) references in viewcontroller and then when the text changes :

- (void)textViewDidChange:(UITextView *)textView { 
    [self.textView sizeToFit];
    self.containerViewTrailingConstraint.constant = self.textView.contentSize.width; 
    self.containerViewConstraintWithBottom.constant = self.textView.contentSize.height; 
    [self.view layoutIfNeeded];
}

And when the textView is hidden then you have to set the self.containerViewTrailingConstraint.constant, self.containerViewConstraintWithBottom.constant in relation with the imageView