[IOS]图片的旋转和缩放
实现图片的旋转和缩放也是IOS开发中一个比较常见的技术点，下面我们来一起学习，这功能如何实现？效果图： 运行的时候按住alt键能够实现图片的伸缩ViewController.h:

#import "ViewController.h"#import "MyGestureRecongnizer.h"  //自定义手势@interface ViewController ()@end@implementation ViewController- (void)viewDidLoad{    [super viewDidLoad];    prviousScale=1;    //缩放手势    UIPinchGestureRecognizer *pin=[[UIPinchGestureRecognizer alloc]initWithTarget:self action:@selector(doPinch:)];    pin.delegate=self;    [self.otherImage addGestureRecognizer:pin];        //旋转事件    UIRotationGestureRecognizer *rotaion=[[UIRotationGestureRecognizer alloc]initWithTarget:self action:@selector(doRotate:)];    rotaion.delegate =self;    [self.otherImage addGestureRecognizer:rotaion];            //添加自定义手势(点击到X大于200的地方相应)    MyGestureRecongnizer *my = [[MyGestureRecongnizer alloc] initWithTarget:self action:@selector(fun:)];    [self.view addGestureRecognizer:my];        }//自定义手势触发事件-(void)fun:(MyGestureRecongnizer *)my{    NSLog(@"OK");}//允许同时调用两个手势,如果是no的话就只能调用一个手势-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{    return YES;}-(void)transfromImageView{    CGAffineTransform t=CGAffineTransformMakeScale(scale*prviousScale, scale*prviousScale);    t=CGAffineTransformRotate(t, rotation+previousRotation);    self.otherImage.transform=t;}//缩放方法-(void)doPinch:(UIPinchGestureRecognizer *)gesture{    scale=gesture.scale; //缩放倍数    [self transfromImageView];    if (gesture.state==UIGestureRecognizerStateEnded) {        prviousScale=scale*prviousScale;        scale=1;    }}//旋转方法-(void)doRotate:(UIRotationGestureRecognizer *)gesture{    rotation=gesture.rotation; //旋转角度    [self transfromImageView];    if (gesture.state==UIGestureRecognizerStateEnded) {        previousRotation=rotation+previousRotation;        rotation=0;    }}- (void)dealloc {    [_otherImage release];    [super dealloc];}@end