IOS动画 旋转两圈

//

//  ViewController.m

//  KeyFrameAnimation

//

//  Created by vincent_guo on 13-9-6.

//  Copyright (c) 2013年 vincent_guo. All rights reserved.

//

 

#import "ViewController.h"

#import <QuartzCore/QuartzCore.h>

 

@interface ViewController (){

    UIImageView *_imageView;

}

 

@end

 

@implementation ViewController

 

- (void)viewDidLoad

{

    [super viewDidLoad];

    // Do any additional setup after loading the view, typically from a nib.

    _imageView = [[UIImageView alloc] init];

    _imageView.bounds = CGRectMake(0, 0, 80, 80);

    _imageView.center = CGPointMake(160, 50);

    _imageView.image = [UIImage imageNamed:@"clock"];

    [self.view addSubview:_imageView];

    [_imageView release];

}

 

-(void)click:(id)sender{

    [self turnTwoRound2];

}

 

#pragma mark 使用CABasicAnimation让View向左转两圈，要向右转两圈，把-M_PI负号去掉就可以了

-(void)turnTwoRound1 {

    CABasicAnimation* rotationAnimation;

    rotationAnimation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.z"];

    rotationAnimation.toValue = [NSNumber numberWithFloat: -M_PI * 2.0 ];

    rotationAnimation.duration = 0.5;

    rotationAnimation.repeatCount = 2;//动画执行两次

    [_imageView.layer addAnimation:rotationAnimation forKey:@"rotationAnimation"];

}

 

 

#pragma mark 使用CAKeyframeAnimation让View向左转两圈，要向右转两圈，把-M_PI负号去掉就可以了

-(void)turnTwoRound2{

    CAKeyframeAnimation *rotateAnimation = [CAKeyframeAnimation animationWithKeyPath:@"transform.rotation.z"];

    rotateAnimation.duration = 0.5;

    //先从原始位置向左转180度，再向左转180度是-M_PI*4,不是-M_PI*2哦，自己好好理解下)

    rotateAnimation.values = [NSArray arrayWithObjects:

                              [NSNumber numberWithFloat:0.0f],

                              [NSNumber numberWithFloat:-M_PI * 2],

                              [NSNumber numberWithFloat:-M_PI * 4], nil];

    [_imageView.layer addAnimation:rotateAnimation forKey:@"rotationAnimation"];

}

 

@end

转自：http://www.cnblogs.com/vincent-guo/p/3305428.html