Frame Animation with CGAffineTransform

One of the most powerful and useful property of UIView is transform, which takes a CGAffineTransform. This is a matrix that express how each pixel of UIView should be modified, applying some mathematical formulas.

CGAffineTransformScale: CGAffineTransformScale use for scale a view up and down. A transform value of 5.0 means make the view 5 times bigger than actual frame.

CGAffineTransformRotate: Use for rotate a view by given angle. It uses radian.


Here a piece of code for render a view  with animation from center.

UIImageView *aniView;

//method for display subview.
-(void) displaySubView{
    //Create object for sub view
    if (!aniView) {
        aniView = [[UIImageView alloc] initWithFrame:CGRectMake(self.view.center.x, self.view.center.y, 0, 0)];
        aniView.backgroundColor = [UIColor clearColor];
        aniView.image = [UIImage imageNamed:@"imagename.png"];
        aniView.clipsToBounds = YES;
        aniView.center = self.view.center;
      // Reduce view to 1/10th of its original frame
        aniView.transform = CGAffineTransformScale(aniView.transform, .01, .01);
        [self.view addSubview:aniView];
    }
    [UIView animateWithDuration:1 animations:^{
        // return the view to original frame
        aniView.transform = CGAffineTransformScale(aniView.transform, 100, 100);
      
    }];
}
//Method for hide subview
-(void) hideSubView{
    [UIView animateWithDuration:1 animations:^{
        aniView.transform = CGAffineTransformScale(aniView.transform, .01, .01);
    }];
}