Calculate constraint update based on converted rect.

[markst]

    UIView * superview = [(UIView *)self.firstItem superview];
    CGRect keyboardFrame = [superview.window convertRect:keyboardFrame toView:superview.superview];
    CGFloat inset = superview.frame.origin.y + superview.frame.size.height - keyboardFrame.origin.y;

[ezescaruli]

@markst This could be of your interest: 885d7fb

I'm basically doing [superview convertRect:superview.bounds toView:nil], to use that view's frame relative to the current window, before subtracting CGRectGetMinY(endFrame).

My logic behind that is that endFrame is always relative to the current window, so the subtraction should use two rects in the same coordinate system.