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(100, 100, 100, 100)];
 _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(0, 0, 200, 200)];
    imgv.center = self.view.center;
    [self.view addSubview:imgv];
    imgv.image = [UIImage imageNamed:@"3"];
    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 = 2;
    
    //设置该手势的点击次数
    tap.numberOfTapsRequired = 4;
    [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