iOS手勢識別的詳細(xì)使用（拖動(dòng)，縮放，旋轉(zhuǎn)，點(diǎn)擊，手勢依賴,自定義手勢）1、UIGestureRecognizer介紹手勢識別在iOS上非常重要，手勢操作移動(dòng)設(shè)備的重要特征，極大的增加了移動(dòng)設(shè)備使用便捷性。iOS系統(tǒng)在3.2以后，為方便開發(fā)這使用一些常用的手勢，提供了UIGestureRecognizer類。手勢識別UIGestureRecognizer類是個(gè)抽象類，下面的子類是具體的手勢，開發(fā)這可以直接使用這些手勢識別。UITapGestureRecognizerUIPinchGestureRecognizerUIRotationGestureRecognizerUISwipeGestureRecognizerUIPanGestureRecognizerUILongPressGestureRecognizer上面的手勢對應(yīng)的操作是：Tap（點(diǎn)一下）Pinch（二指往內(nèi)或往外撥動(dòng)，平時(shí)經(jīng)常用到的縮放）Rotation（旋轉(zhuǎn)）Swipe（滑動(dòng)，快速移動(dòng)）Pan（拖移，慢速移動(dòng)）LongPress（長按）UIGestureRecognizer的繼承關(guān)系如下：-Q_ UlFont J)|p(LJJLcngPressGestureReco^niaefc、UiGeslureRecognizerIfUIPanGestureRecognizer]、 UHmage )UIPinchGeslureRecogniizer乂UlLocalizedhdexedColiation')-QJlFlotationGestureReGognizer■yUlLocalNotificationj〈UlSwipeGestureFlecognizer、UlMenuContrailer)￡UITapGestureRecogriize<」[ NSObject J—-( UlMenultem )2、 使用手勢的步驟使用手勢很簡單，分為兩步：創(chuàng)建手勢實(shí)例。當(dāng)創(chuàng)建手勢時(shí)，指定一個(gè)回調(diào)方法，當(dāng)手勢開始，改變、或結(jié)束時(shí)，回調(diào)方法被調(diào)用。2-添加到需要識別的View中。每個(gè)手勢只對應(yīng)一個(gè)View，當(dāng)屏幕觸摸在View的邊界內(nèi)時(shí)，如果手勢和預(yù)定的一樣，那就會(huì)回調(diào)方法。ps：—個(gè)手勢只能對應(yīng)一個(gè)View，但是一個(gè)View可以有多個(gè)手勢。建議在真機(jī)上運(yùn)行這些手勢，模擬器操作不太方便，可能導(dǎo)致你認(rèn)為手勢失效。3、 Pan拖動(dòng)手勢：[cpp]viewplaincopyUllmageView*snakeImageView=[[UllmageViewalloc]initWithImage:[UIImageimageNamed:@"snake.png"]];snakelmageView.frame=CGRectMake(50,50,100,160);UIPanGestureRecognizer*panGestureRecognizer=[[UIPanGestureRecognizeralloc]initWithTarget:selfaction:@selector(handlePan:)];[snakeImageViewaddGestureRecognizer:panGestureRecognizer];[self.viewsetBackgroundColor:[UIColorwhiteColor]];[self.viewaddSubview:snakeImageView];新建一個(gè)ImageView,然后添加手勢回調(diào)方法：[cpp]viewplaincopy一(void)handlePan:(UIPanGestureRecognizer*)recognizer{CGPointtranslation=[recognizertranslationInView:self.view];recognizer.view.center=CGPointMake(recognizer.view.center.x+translation.x,recognizer.view.center.y+translation.y);[recognizersetTranslation:CGPointZeroinView:self.view];7.8?}4、Pinch縮放手勢[cpp]viewplaincopyUIPinchGestureRecognizer*pinchGestureRecognizer=[[UIPinchGestureRecognizeralloc]initWithTarget:selfaction:@selector(handlePinch:)];<pclass="p1">[<spanclass="s1"〉snakeImageView</span><spanclass="s2"〉addGestureRecognizer</span〉：pinchGestureRecognizer]；</p>[cpp]viewplaincopy1.一(void)handlePinch:(UIPinchGestureRecognizer*)recognizer2?{recognizer.view.transform=CGAffineTransformScale(recognizer.view.transform,recognizer.scale,recognizer.scale);recognizer.scale=1;5?}5、Rotation旋轉(zhuǎn)手勢[cpp]viewplaincopy1.UIRotationGestureRecognizer*rotateRecognizer=[[UIRotationGestureRecognizeralloc]2.3.initWithTarget:self2.3.action:@selector(handleRotate:)];[snakelmageViewaddGestureRecognizer:rotateRecognizer];[cpp]viewplaincopy1.一(void)handleRotate:(UIRotationGestureRecognizer*)recognizer2?{recognizer.view.transform=CGAffineTransformRotate(recognizer.view.transform,recognizer.rotation);recognizer.rotation=0;6二■V/~/\\\\□CarrierW 4:21PM添加了這幾個(gè)手勢后，運(yùn)行看效果，程序中的6二■V/~/\\\\□CarrierW 4:21PM添加了這幾個(gè)手勢后，運(yùn)行看效果，程序中的imageview放了一個(gè)/W\」_10|'\\\的圖片，在模擬器上拖動(dòng)是沒問題的?？s放和旋轉(zhuǎn)有點(diǎn)問題，估計(jì)是因?yàn)樵谀M器上的模擬的兩個(gè)接觸點(diǎn)距離在imageView的邊界外了，所以操作無效果。建議在真機(jī)上運(yùn)行這個(gè)手勢。在模擬器上縮放和選擇的操作技巧:可以把imageView的frame值設(shè)置大一點(diǎn)，按住alt鍵，按下觸摸板（不按下不行），這樣就可以旋轉(zhuǎn)和縮放了。6、添加第二個(gè)ImagView并添加手勢記?。阂粋€(gè)手勢只能添加到一個(gè)View，兩個(gè)View當(dāng)然要有兩個(gè)手勢的實(shí)例了[cpp]viewplaincopy-(void)viewDidLoad{[superviewDidLoad];4.UIImageView*snakeImageView=[[UIImageViewalloc]initWithImage:[UIImageimageNamed:@"snake.png"]];UIImageView*dragonImageView=[[UIImageViewalloc]initWithImage:[UIImageimageNamed:@"dragon.png"]];snakeImageView.frame=CGRectMake(120,120,100,160);dragonImageView.frame=CGRectMake(50,50, 100,160);[self.viewaddSubview:snakeImageView];[self.viewaddSubview:dragonImageView];11.for(UIView*viewinself.view.subviews) {UIPanGestureRecognizer*panGestureRecognizer=[[UIPanGestureRecognizeralloc]

14.15.16.17.18.19.20.21.22.23.24.25.26.27.28.29.30.31.initWithTarget:selfaction:@selector(handlePan:)];UIPinchGestureRecognizer*pinchGestureRecognizer=[[UIPinchGestureRecognizeralloc]initWithTarget:selfaction:@selector(handlePinch:)];UIRotationGestureRecognizer*rotateRecognizer=[[UIRotationGestureRecognizeralloc]initWithTarget:selfaction:@selector(handleRotate:)];[viewaddGestureRecognizer:panGestureRecognizer];[viewaddGestureRecognizer:pinchGestureRecognizer];[viewaddGestureRecognizer:rotateRecognizer];[viewsetUserInteractionEnabled:YES];}[self.viewsetBackgroundColor:[UIColorwhiteColor]];}多添加了一條龍的view，兩個(gè)view都能接收上面的三種手勢。運(yùn)行效果如下:

7、拖動(dòng)（pan手勢）速度（以較快的速度拖放后view有滑行的效果）如何實(shí)現(xiàn)呢?監(jiān)視手勢是否結(jié)束監(jiān)視觸摸的速度[cpp]viewplaincopy一(void)handlePan:(UIPanGestureRecognizer*)recognizer{CGPointtranslation=[recognizertranslationInView:self.view];recognizer.view.center=CGPointMake(recognizer.view.center.x+translation.x,recognizer.view.center.y+translation?y);[recognizersetTranslation:CGPointZeroinView:self.view];7if(recognizer.state==UIGestureRecognizerStateEnded){9.CGPointvelocity=[recognizervelocityInView:self.view];CGFloatmagnitude=sqrtf((velocity.x*velocity.x)+(velocity.y*velocity.y));CGFloatslideMult=magnitude/200;NSLog(@"magnitude:%f,slideMult:%f",magnitude,slideMult);14.floatslideFactor=0.1*slideMult;//IncreaseformoreofaslideCGPointfinalPoint=CGPointMake(recognizer.view.center.x+(velocity.x*slideFactor),recognizer.view.center.y+(velocity.y*slideFactor));finalPoint.x=MIN(MAX(finalPoint.x,0),self.view.bounds.size.width);finalPoint.y=MIN(MAX(finalPoint.y,0),self.view.bounds.size.height);20.[UIViewanimateWithDuration:slideFactor*2delay:0options:UIViewAnimationOptionCurveEaseOutanimations:^recognizer.view.center=finalPoint;}completion:nil];24.}26.代碼實(shí)現(xiàn)解析：計(jì)算速度向量的長度(估計(jì)大部分都忘了)這些知識了。如果速度向量小于200,那就會(huì)得到一個(gè)小于的小數(shù)，那么滑行會(huì)很短基于速度和速度因素計(jì)算一個(gè)終點(diǎn)確保終點(diǎn)不會(huì)跑出父View的邊界5-使用UIView動(dòng)畫使view滑動(dòng)到終點(diǎn)運(yùn)行后，快速拖動(dòng)圖像view放開會(huì)看到view還會(huì)在原來的方向滑行一段路。&同時(shí)觸發(fā)兩個(gè)view的手勢手勢之間是互斥的，如果你想同時(shí)觸發(fā)蛇和龍的view，那么需要實(shí)現(xiàn)協(xié)議

UIGestureRecognizerDelegate,[cpp]viewplaincopy?interfaceViewController:UIViewController<UIGestureRecognizerDelegate>@end并在協(xié)議這個(gè)方法里返回YES。[cpp]viewplaincopy-(BOOL)gestureRecognizer:(UIGestureRecognizer*)gestureRecognizershouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer*)otherGestureRecognizer{returnYES;}把self作為代理設(shè)置給手勢：[cpp]viewplaincopypanGestureRecognizer.delegate=self;pinchGestureRecognizer.delegate=self;rotateRecognizer.delegate=self;這樣可以同時(shí)拖動(dòng)或旋轉(zhuǎn)縮放兩個(gè)view了。9、tap點(diǎn)擊手勢這里為了方便看到tap的效果，當(dāng)點(diǎn)擊一下屏幕時(shí)，播放一個(gè)聲音。為了播放聲音，我們加入AVFoundation.framework這個(gè)框架。[cpp]viewplaincopy一(AVAudioPlayer*)loadWav:(NSString*)filename{NSURL*url=[[NSBundlemainBundle]URLForResource:filenamewithExtension:@"wav"];NSError*error;AVAudioPlayer*player=[[AVAudioPlayeralloc]initWithContentsOfURL:urlerror:&error];if(!player){NSLog(@"Errorloading%@:%@",url,error.localizedDescription);}else {[playerprepareToPlay];9? }10. return player;

}我會(huì)在最后例子代碼給出完整代碼，添加手勢的步驟和前面一樣的。[cpp]viewplaincopy#import<UIKit/UIKit.h〉#import<AVFoundation/AVFoundation.h〉3.?interfaceViewController:UIViewController<UIGestureRecognizerDelegate>@property(strong)AVAudioPlayer*chompPlayer;@property(strong)AVAudioPlayer*hehePlayer;7.@end[cpp]viewplaincopy一(void)handleTap:(UITapGestureRecognizer*)recognizer{[self.chompPlayerplay];3?}運(yùn)行，點(diǎn)一下某個(gè)圖，就會(huì)播放一個(gè)咬東西的聲音。不過這個(gè)點(diǎn)擊播放聲音有點(diǎn)缺陷，就是在慢慢拖動(dòng)的時(shí)候也會(huì)播放。這使得兩個(gè)手勢重合了。怎么解決呢？使用手勢的：requireGestureRecognizerToFail方法。10、 手勢的依賴性在viewDidLoad的循環(huán)里添加這段代碼：[cpp]viewplaincopy[tapRecognizerrequireGestureRecognizerToFail:panGestureRecognizer];意思就是，當(dāng)如果pan手勢失敗，就是沒發(fā)生拖動(dòng)，才會(huì)出發(fā)tap手勢。這樣如果你有輕微的拖動(dòng)，那就是pan手勢發(fā)生了。tap的聲音就不會(huì)發(fā)出來了。11、 自定義手勢自定義手勢繼承：UIGestureRecognizer，實(shí)現(xiàn)下面的方法：[cpp]viewplaincopy—touchesBegan:withEvent:—touchesMoved:withEvent:—touchesEnded:withEvent:一touchesCancelled:withEvent:

新建一個(gè)類，繼承UIGestureRecognizer,代碼如下:.h文件[cpp]viewplaincopy#import<UIKit/UIKit.h〉typedefenum{Directionunknown =0,DirectionLeft,DirectionRight}Direction;7.8.?interfaceHappyGestureRecognizer:UIGestureRecognizer?property(assign)?property(assign)?property(assign)?property(assign)?property(assign)inttickleCount;CGPointcurTickleStart;DirectionlastDirection;12.13.@end.m文件[cpp]viewplaincopy#import"HappyGestureRecognizer.h"#import<UIKit/UIGestureRecognizerSubclass.h>#defineREQUIRED_TICKLES 2#defineMOVE_AMT_PER_TICKLE 255.?implementationHappyGestureRecognizer7.-(void)touchesBegan:(NSSet*)toucheswithEvent:(UIEvent*)event{UITouch*touch=[touchesanyObject];self.curTickleStart=[touchlocationInView:self.view];}12.13.14.15.16.17.13.14.15.16.17.18.19.20.21.22.(void)touchesMoved:(NSSet*)toucheswithEvent:(UIEvent*)event{//Makesurewe'vemovedaminimumamountsincecurTickleStartUITouch*touch=[touchesanyObject];CGPointticklePoint=[touchlocationInView:self.view];CGFloatmoveAmt=ticklePoint.x-self.curTickleStart.x;DirectioncurDirection;if(moveAmt<0) {curDirection=DirectionLeft;}else{24.25.26.27.28.29.30.31.32.33.34.35.36.37.38.39.40.41.42.43.44.45.4 6.47.48.49.50.51.52.53.54.55.5 6.57.58.59.60.61.62.63.64.}if(ABS(moveAmt)<MOVE_AMT_PER_TICKLE)return;//確認(rèn)方向改變了if(self.lastDirection==Directionunknown||(self.lastDirection==DirectionLeft&&curDirection==DirectionRight)||(self.lastD