How to animate the width and height of a UIView in Xcode?

Question

I have this subview I want to add to my main view, but make it expand from the origin. I read some of the Apple documentation but I don't understand where I am making mistake. I can animate the origin of the frame, i.e. to get it slide in from wherever, but the width/height doesn't seem to animate. Code as follows:

[UIView beginAnimations:@"animateAddContentView" context:nil]; [UIView setAnimationDuration:0.4]; customView.frame= CGRectMake(self.view.frame.origin.x +5, self.view.frame.origin.y +5, 0, 150); [self.view addSubview:customView];  customView.frame= CGRectMake(self.view.frame.origin.x +5, self.view.frame.origin.y +5, 310, 150); [UIView commitAnimations]; 

I have also tried putting only the setFrame part in the animation like this:

customView.frame= CGRectMake(self.view.frame.origin.x +5, self.view.frame.origin.y +5, 0, 150); [self.view addSubview:customView]; [UIView beginAnimations:@"animateAddContentView" context:nil]; [UIView setAnimationDuration:0.4]; customView.frame= CGRectMake(self.view.frame.origin.x +5, self.view.frame.origin.y +5, 310, 150); [UIView commitAnimations]; 

But it still doesn't work!

EDIT:

As per the suggestions, I have moved it to a block based animation solution, and this is the exact code:

NSLog(@"yourview : %@",customView); customView.frame= CGRectMake(self.view.frame.origin.x +5, self.view.frame.origin.y +5, 0, 150);  NSLog(@"yourview : %@",customView); [self.view addSubview:customView]; NSLog(@"yourview : %@",customView);  //    [customView setFrame:CGRectMake( 0.0f, 480.0f, customView.frame.size.width, customView.frame.size.height)];  [UIView animateWithDuration:0.4                       delay:0                     options:UIViewAnimationCurveEaseInOut                  animations:^ {                      NSLog(@"yourview : %@",customView);                       customView.frame = CGRectMake(self.view.frame.origin.x +5, self.view.frame.origin.y +5, 310, 150);                      NSLog(@"yourview : %@",customView);                   }completion:^(BOOL finished) {                   }]; 

Which still doesn't work for some reason. Possible problems I see are:

1. I am loading this customView from a nib that is specifically 310 by 150, perhaps that is causing a problem.
2. I am not importing the correct frameworks, but since I can animate the frame.origin parts of this view, I am not sure that is the case...I have QuartzCore and Core Graphics all imported and stuff.

At each point in the log it is giving the correct stuff: for example, before the target frame the size is 0, 150, and after I set the frame its 310, 150. But the animation doesn't work!

Answer 1

To make a view "grow" into place, don't animate the frame. Animate the transform.

Load your subview from the nib. Set its transform to a scale of 0:

view.transform = CGAffineTransformMakeScale(0,0); 

Then add it to your superview.

Inside the animation block, set the transform to identity:

view.transform = CGAffineTransformIdentity; 

And the view will grow to normal size. You may need to fiddle with the anchor point to make it grow from the right point.

You can also change the frame within the block, but to move a view only I prefer to change the center property, you shouldn't try to set the frame if you also have a transform.

For bonus points, you can also animate to a slightly bigger than 1.0 scale, then animate back to the identity transform in a chained animation from the completion block. This makes the view "pop" out of the screen like an alert view.

Answer 2

Try using a block it will be more clear.

 // First create the view if you haven't already  UIView *myView = [[UIView alloc] initWithFrame:CGRectMake(0.0f, 0.0f, 100.0f, 100.0f)];  // Add it as a subview.  [myViewController.view addSubview:myView];    CGRect newFrameOfMyView = CGRectMake(0.0f, 0.0f, 200.0f, 200.0f);  /*  * Alternatively you could just set the width/height or whatever you'd like with this:   * CGRect newFrameOfMyView = myView.frame;   * newFrameOfMyView.size.height = 200.0f;   * newFrameOfMyView.size.width = 200.0f;   */ [UIView animateWithDuration:0.3f      animations:^{       myView.frame = newFrameOfMyView;       }      completion:^(BOOL finished){       NSLog( @"woo! Finished animating the frame of myView!" );  }];