CGAffineTransformMakeRotation和CGAffineTransformScale

@interface
ViewController ()

{

float angle;

UIImageView *imageView;

}

@end

@implementation ViewController

- (void)viewDidLoad

{

angle = 0.0f;

imageView = [[UIImageView
alloc]initWithImage:[UIImage
imageNamed:@"111.png"]];

imageView.center =
self.view.center;

[self.view
addSubview:imageView];

CGAffineTransform transfrom =
CGAffineTransformMakeRotation(0);

imageView.transform = transfrom;

[self.view
setBackgroundColor:[UIColor
redColor]];//设置背景为红色，效果直观明显

[NSTimer
scheduledTimerWithTimeInterval: 0.01
target: self
selector:@selector(transformAction)
userInfo: nil
repeats: YES];

}

-(void)transformAction {

angle =
angle +
0.01;//angle角度 double angle;

if (angle >
6.28) {//大于 M_PI*2(360度)
角度再次从0开始

angle = 0;

}

CGAffineTransform transform=CGAffineTransformMakeRotation(angle);

imageView.transform = transform;

}

@interface
ViewController ()

{

float angle;

UIImageView *imageView;

}

@end

@implementation ViewController

- (void)viewDidLoad

{

angle = 0.0f;

imageView = [[UIImageView
alloc]initWithImage:[UIImage
imageNamed:@"111.png"]];

imageView.center =
self.view.center;

[self.view
addSubview:imageView];

CGAffineTransform transfrom =
CGAffineTransformMakeRotation(angle);

imageView.transform = transfrom;

[self.view
setBackgroundColor:[UIColor
redColor]];//设置背景为红色，效果直观明显

[NSTimer
scheduledTimerWithTimeInterval: 0.01
target: self
selector:@selector(transformAction)
userInfo: nil
repeats: YES];

}

-(void)transformAction {

angle =
angle +
0.01;//angle角度 double angle;

if (angle >
6.28) {//大于 M_PI*2(360度)
角度再次从0开始

angle = 0;

}

CGAffineTransform transform=CGAffineTransformMakeRotation(angle);

// imageView.transform = transform;

float degree =
cos(angle);

if (degree <0.0f) {

degree *= -1.0f;

}

degree += 0.5f;

CGAffineTransform scaled =
CGAffineTransformScale(transform, degree, degree);

imageView.transform = scaled;

}

- (void)didReceiveMemoryWarning

{

[super
didReceiveMemoryWarning];

// Dispose of any resources that can be recreated.

}

@end