iOS 图片捏合放大缩小 点击放大缩小

此处的图片控件，我用的是UIButton，因为它自身有点击事件，不过UIImageView同理，为其添加手势即可实现同样的效果。

//

//  ServiceResultViewController.m

//  Created by msk on 16/3/7.

//

#import "ServiceResultViewController.h"

static CGRect oldframe;//用于记录按钮放大之前的frame

@interface
ServiceResultViewController ()<UIScrollViewDelegate>{

    

    UIView *imgView;//展示图片的父视图

    NSMutableArray *imagesArray;//存储图片

    CATransition *animation;//缩放动画效果

    CGFloat scaleNum;//图片放大倍数

}

@property(nonatomic,strong)UIScrollView *scrollview;//用于捏合放大与缩小的scrollView

@property(nonatomic,strong)UIButton *imgButton;//显示图片的按钮

@end

@implementation ServiceResultViewController

#pragma mark - 获取图片

- (void)viewDidLoad {

    [super viewDidLoad];

    self.view.backgroundColor=[UIColor whiteColor];

    imagesArray=[NSMutableArray array];

    //获取网络图片并存入到imagesArray中的代码，放到此处,此处以本地图片为例

    for (int i=0; i<5; i++) {

        UIImage *image=[UIImage imageNamed:@"default_head"];

        [imagesArray
addObject:image];

    }

    //然后进行视图的布局,进行图片的显示

    NSInteger rows =imagesArray.count%3==0?imagesArray.count/3:imagesArray.count/3+1;

    CGFloat height = ((WIDTH -20)/3)+2.5;

    imgView = [[UIView alloc]initWithFrame:CGRectMake(0,64,WIDTH,
(10+(5+height)*rows))];

    [self.view addSubview:imgView];

 

    [selfloadImageShowOnView];

}

#pragma mark - 展示图片

-(void)loadImageShowOnView{

    CGRect aRect, bRect, bounds =
CGRectMake(2.5,
10, imgView.bounds.size.width,10000000);    

    NSInteger rows =imagesArray.count%3==0?imagesArray.count/3:imagesArray.count/3+1;

    for (int i =0; i<rows; i++) {

        DivideWithPadding(bounds, &aRect, &bounds,90,5,CGRectMinYEdge);

        for (int m =0; m<3; m++) {

            NSInteger index = i *
3 + m;

            if (index >=
imagesArray.count) {

                return;

            }

            DivideWithPadding(aRect, &bRect, &aRect, bounds.size.width/3-5,5,CGRectMinXEdge);

            UIImage *img= [imagesArray objectAtIndex:index];

            UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];

            button.frame = bRect;

            [button setImage:imgforState:UIControlStateNormal];

            [button addTarget:self action:@selector(enlargeImage:) forControlEvents:UIControlEventTouchUpInside];

            button.exclusiveTouch =YES;//禁止两个按钮同时被点击，引起图片显示错乱现象发生

            [imgView
addSubview:button];

        }

    }

}

#pragma mark - 放大图片

-(void)enlargeImage:(UIButton *)button{

    scaleNum=1;

    UIWindow *window=[UIApplication sharedApplication].keyWindow;

    UIView *backgroundView=[[UIView alloc]initWithFrame:CGRectMake(0,0,
[UIScreen mainScreen].bounds.size.width, [UIScreen mainScreen].bounds.size.height)];

    oldframe=[button
convertRect:button.bounds
toView:imgView];

    backgroundView.backgroundColor=[UIColor blackColor];

    backgroundView.alpha=0;

    button.tag=1;

    

    //添加捏合手势，放大与缩小图片

    self.scrollview=[[UIScrollView alloc]initWithFrame:backgroundView.bounds];

    self.imgButton=button;

    [self.scrollview addSubview:button];

    

    //设置UIScrollView的滚动范围和图片的真实尺寸一致

    self.scrollview.contentSize=button.frame.size;

    //设置实现缩放

    //设置代理scrollview的代理对象

    self.scrollview.delegate=self;

    //设置最大伸缩比例

    self.scrollview.maximumZoomScale=3;

    //设置最小伸缩比例

    self.scrollview.minimumZoomScale=1;

    [self.scrollview setZoomScale:1animated:NO];

    self.scrollview.scrollsToTop =NO;

    self.scrollview.scrollEnabled =YES;

    self.scrollview.showsHorizontalScrollIndicator=NO;

    self.scrollview.showsVerticalScrollIndicator=NO;

    

    [backgroundView addSubview:self.scrollview];

    [window addSubview:backgroundView];

    

    //单击手势

    UITapGestureRecognizer *singleTapGesture = [[UITapGestureRecognizer alloc]initWithTarget:selfaction:@selector(handleSingleTap:)];

    singleTapGesture.numberOfTapsRequired =
1;

    singleTapGesture.numberOfTouchesRequired  =1;

    [backgroundView addGestureRecognizer:singleTapGesture];

    

    //双击手势

    UITapGestureRecognizer *doubleTapGesture = [[UITapGestureRecognizer alloc]initWithTarget:selfaction:@selector(handleDoubleTap:)];

    doubleTapGesture.numberOfTapsRequired =
2;

    doubleTapGesture.numberOfTouchesRequired =1;

    [backgroundView addGestureRecognizer:doubleTapGesture];

    

    [singleTapGesture requireGestureRecognizerToFail:doubleTapGesture];

    

    [UIViewanimateWithDuration:0.3animations:^{

        button.frame=CGRectMake(0,([UIScreen mainScreen].bounds.size.height-(button.frame.size.height*[UIScreen mainScreen].bounds.size.width/button.frame.size.width+80))/2,
[UIScreen mainScreen].bounds.size.width, button.frame.size.height*[UIScreen mainScreen].bounds.size.width/button.frame.size.width+80);

        backgroundView.alpha=1;

    } completion:^(BOOL finished) {

        button.userInteractionEnabled=NO;

    }];

}

#pragma mark - 还原图片

-(void)hideImage:(UITapGestureRecognizer*)tap{

    UIView *backgroundView=tap.view;

    UIButton *button=(UIButton *)[tap.viewviewWithTag:1];    

    animation = [CATransition
animation];

    animation.duration =0.2;

    animation.timingFunction =UIViewAnimationCurveEaseInOut;

    animation.fillMode =kCAFillModeForwards;

    animation.type =kCATransition;

    backgroundView.alpha=0;

    [backgroundView.layer
addAnimation:animation
forKey:@"animation"];

    button.frame=oldframe;

    [imgView addSubview:button];

    button.userInteractionEnabled=YES;

}

#pragma mark - 处理单击手势

-(void)handleSingleTap:(UIGestureRecognizer *)sender{    

    UITapGestureRecognizer *tap=(UITapGestureRecognizer *)sender;

    [self hideImage:tap];

}

#pragma mark - 处理双击手势

-(void)handleDoubleTap:(UIGestureRecognizer *)sender{

    if (scaleNum>=1&&scaleNum<=2)
{

        scaleNum++;

    }else{

        scaleNum=1;

    }

    [self.scrollviewsetZoomScale:scaleNumanimated:YES];

}

#pragma mark - UIScrollViewDelegate,告诉scrollview要缩放的是哪个子控件

-(UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView{

    return
self.imgButton;

}

#pragma mark - 等比例放大，让放大的图片保持在scrollView的中央

- (void)scrollViewDidZoom:(UIScrollView *)scrollView{

    CGFloat offsetX = (self.scrollview.bounds.size.width
> self.scrollview.contentSize.width)?(self.scrollview.bounds.size.width
- self.scrollview.contentSize.width) *0.5
: 0.0;

    CGFloat offsetY = (self.scrollview.bounds.size.height
> self.scrollview.contentSize.height)?

    (self.scrollview.bounds.size.height
- self.scrollview.contentSize.height) *0.5
: 0.0;

    self.imgButton.center =CGPointMake(self.scrollview.contentSize.width
*0.5 + offsetX,self.scrollview.contentSize.height *0.5
+ offsetY);

}

#pragma mark - 自动排列图片

void DivideWithPadding(CGRect rect,CGRect *slice,CGRect *remainder,CGFloat amount,CGFloat
padding,CGRectEdge edge) {

    CGRect tmpSlice;

    CGRectDivide(rect, &tmpSlice, &rect, amount, edge);

    if (slice) {

        *slice = tmpSlice;

    }

    CGRectDivide(rect, &tmpSlice, &rect, padding, edge);

    if (remainder) {

        *remainder = rect;

    }

}

- (void)didReceiveMemoryWarning {

    [superdidReceiveMemoryWarning];

    // Dispose of any resources that can be recreated.

}

@end