iOS 实现转盘的效果

效果

#import "ViewController.h"

@interface ViewController ()
@property (weak, nonatomic) IBOutlet UIImageView *panImageView;
/**  */
@property(nonatomic,assign)int angle;
/** 转盘时间 */
@property(strong,nonatomic)NSTimer *timer;
/** 计时器 */
@property(strong,nonatomic)NSTimer *timeTick;
/** 计时时间 */
@property(nonatomic,assign)int timeNumber;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    self.timeNumber = 3;
   self.timer = [NSTimer scheduledTimerWithTimeInterval:0.01 target:self selector:@selector(startAnimation) userInfo:nil repeats:YES];
    self.timeTick = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(timeFireMethod) userInfo:nil repeats:YES];

}
-(void)startAnimation
{
    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDuration:1];
    [UIView setAnimationDelegate:self];
    _panImageView.animationRepeatCount = 1;
//    [UIView setAnimationDidStopSelector:@selector(startAnimation)];
    self.angle += 1000;
    self.panImageView.layer.anchorPoint = CGPointMake(0.5,0.5);//以右下角为原点转，（0,0）是左上角转，（0.5,0,5）心中间转，其它以此类推
    self.panImageView.transform = CGAffineTransformMakeRotation(self.angle * (M_PI / 180.0f));

    [UIView commitAnimations];

}

-(void)timeFireMethod{
    self.timeNumber -- ;
    if (self.timeNumber == 0) {
        [self.timer invalidate];
    }

}
@end