UIView animated changes with auto layout constraints

Question

Say that I have a project which looks like the following:

There are tw

Answer 1

//
//  WPViewController.h
//  AutoLayoutTEst
//
//  Created by VASANTH K on 09/01/14.
//  
//

#import 

@interface WPViewController : UIViewController
@property (strong, nonatomic) IBOutlet UIButton *button1;
- (IBAction)buttClicked:(id)sender;
@property (strong, nonatomic) IBOutlet NSLayoutConstraint *heightConstrain;

@property (strong, nonatomic) IBOutlet UIButton *button2;
@end

click Event

- (IBAction)buttClicked:(id)sender {


    self.heightConstrain.constant=100;


}

here u need to set the heightConstrain for the Yellow button then create reference outlet for that button then update the heightConstrain to update the size of that button it will automatically move your Red button down.

https://github.com/vasanth3008/AutoLayoutHeighDemo

refer my sample demo project