iOS阶段学习第35天笔记(Touch手势介绍)

一、Touch手势

1、利用手势实现UIButton移动效果  实例代码

1） 创建一个继承自UIButton的类 MyButton.h  代码实现

 #import <UIKit/UIKit.h>
 @interface MyButton : UIButton
 @end

2）MyButton.m  的代码实现

 #import "MyButton.h"
 @implementation MyButton
 {
     CGPoint _lastPoint;
 }

 //手势开始
 -(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
 {
     UITouch *touch = [touches anyObject];
     CGPoint point = [touch locationInView:self];
     NSLog(@"began:%@",NSStringFromCGPoint(point));
     _lastPoint = point;
 }

 -(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
 {
     UITouch *touch = [touches anyObject];
     CGPoint point = [touch locationInView:self];
     CGFloat offsetx = point.x - _lastPoint.x;
     CGFloat offsety = point.y - _lastPoint.y;
     self.center = CGPointMake(self.center.x + offsetx, self.center.y + offsety);
     NSLog(@"moved:%@",NSStringFromCGPoint(point));
 }

 -(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
 {
     UITouch *touch = [touches anyObject];
     CGPoint point = [touch locationInView:self];
     NSLog(@"end:%@",NSStringFromCGPoint(point));
 }
 @end 

3）父视图中的代码实现

 #import "ViewController.h"
 #import "MyButton.h"
 @interface ViewController ()
 {
     MyButton *_v;
     CGPoint _lastPoint;
 }
 @end

 @implementation ViewController

 - (void)viewDidLoad {
     [super viewDidLoad];
     _v = [[MyButton alloc]initWithFrame:CGRectMake(, , , )];
  _v.backgroundColor = [UIColor redColor];
     [self.view addSubview:_v];
 }

 //手势开始
 -(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
 {
     UITouch *touch = [touches anyObject];
     CGPoint point = [touch locationInView:self.view];
     NSLog(@"began:%@",NSStringFromCGPoint(point));
     _lastPoint = point;
 }

 -(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
 {
     UITouch *touch = [touches anyObject];
     CGPoint  point = [touch locationInView:self.view];
     CGFloat  offsetx = point.x - _lastPoint.x;
     CGFloat  offsety = point.y - _lastPoint.y;
     _v.center = CGPointMake(_v.center.x + offsetx, _v.center.y + offsety);
     _lastPoint = point;
     NSLog(@"moved:%@",NSStringFromCGPoint(point));
 }

 -(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
 {
     UITouch *touch = [touches anyObject];
     CGPoint  point = [touch locationInView:self.view];
     NSLog(@"end:%@",NSStringFromCGPoint(point));
 }

 -(void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
 {

 }
 @end

2、利用Touch手势实现控件的缩放与旋转效果 实例代码

 #import "ViewController.h"
 //遵守旋转与缩放的代理协议
 @interface ViewController ()<UIGestureRecognizerDelegate>
 @end

 @implementation ViewController

 - (void)viewDidLoad {
     [super viewDidLoad];

     UIImageView *imgv = [[UIImageView alloc]initWithFrame:CGRectMake(, , , )];
     imgv.center = self.view.center;
     [self.view addSubview:imgv];
     imgv.image = [UIImage imageNamed:@""];
     imgv.userInteractionEnabled = YES;

     //点击手势
     UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(tapGes:)];

     //设置该手势需要的手指数
     tap.numberOfTouchesRequired = ;

     //设置该手势的点击次数
     tap.numberOfTapsRequired = ;
     [imgv addGestureRecognizer:tap];

     //平移手势,拖拽手势
     UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(panGes:)];
     [imgv addGestureRecognizer:pan];

     //缩放手势
     UIPinchGestureRecognizer *pinch = [[UIPinchGestureRecognizer alloc]initWithTarget:self action:@selector(pinchGes:)];
     [imgv addGestureRecognizer:pinch];
     pinch.delegate = self;

     //旋转
     UIRotationGestureRecognizer *rotation = [[UIRotationGestureRecognizer alloc]initWithTarget:self action:@selector(rotationGes:)];
     [imgv addGestureRecognizer:rotation];
     rotation.delegate = self;
 }

 //返回值表示能否同时识别其他(相对于已经设置了代理的手势)手势
 - (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:
     (UIGestureRecognizer *)otherGestureRecognizer
 {
     return YES;
 }
 -(void)rotationGes:(UIRotationGestureRecognizer *)rotation
 {
     rotation.view.transform = CGAffineTransformRotate(rotation.view.transform, rotation.rotation);
     rotation.rotation = 0.0;
 }
 -(void)pinchGes:(UIPinchGestureRecognizer *)pinch
 {
     //transform:仿射变换
     //pinch.scale,是缩放手势的捏合倍率
     pinch.view.transform = CGAffineTransformScale(pinch.view.transform, pinch.scale, pinch.scale);

     //倍率还原
     pinch.scale = 1.0;
 }
 -(void)panGes:(UIPanGestureRecognizer *)pan
 {
     //返回当前的手势的偏移量
     CGPoint offset = [pan translationInView:pan.view];
     //pan.view就是pan手势所加到的视图
     pan.view.center = CGPointMake(pan.view.center.x + offset.x, pan.view.center.y + offset.y);
     //移动以后,把偏移量归0
     [pan setTranslation:CGPointZero inView:pan.view];
 }

 -(void)tapGes:(UIGestureRecognizer *)tap
 {
     NSLog(@"==========");
 }
 @end