UIView+Constraints

UIView+Constraints is a Objective-C category on UIView, giving you a quick and convenient way to get constrains from a UIView (or any of it's subclasses).

UIView+Constraints gives you all you need to move and resize a view. The following is available:

• topConstraint
• leftConstraint
• bottomConstraint
• rightConstraint
• widthConstraint
• heightConstraint

Only constraints added by the UIView by a developer, either in code or in a XIB/Storyboard are handled. If the requested constraint is not set, it will return nil.

####How to use:

@interface MyViewController()

// IBOutlet to inferace builder, has a width constraint
@property (nonatomic, weak) IBOutlet UIView *demoView;

@end

@implementation MyViewController

- (void)resizeView {
    // Request the widthConstraint, and set a new constant
    self.demoView.widthConstraint.constant = 150;
    // Let the view layout itself to apply the new constraint constant
    [self.demoView layoutIfNeeded];
}

- (void)resizeViewWithAnimation {
    // Request the widthConstraint, and set a new constant
    self.demoView.widthConstraint.constant = 150;
    // Contain layoutIfNeeded in an animation block to animate the width change
    [UIView animateWithDuration:0.3 animations:^{
        // Let the view layout itself to apply the new constraint constant
        [self.demoView layoutIfNeeded];
    }];
}

@end

####Planned updates:

• Setting values to existing constraints easier
• Creating constraints from scratch without hassle
• Whatever is requested :-)