iOS 图片裁剪

typedef void(^ImageCropCompleteBlock)(UIImage *);
@interface YXTestController : UIViewController

@property (nonatomic, strong) UIImage * originalImage;
@property (nonatomic, copy) ImageCropCompleteBlock complete;

@end

#import "YXTestController.h"

@interface YXTestController ()
@property (nonatomic, strong) UIImageView * imageView;
@property (nonatomic, strong) UIView * maskView;
@property (nonatomic, assign) CGRect cutRect;

@property (nonatomic, assign) CGSize imageMinSize;
@property (nonatomic, assign) BOOL isWideImg;
@end

@implementation YXTestController {
    CGFloat _viewWeidth;
    CGFloat _viewHeight;
    CGFloat _animationTime;
    CGFloat _maxScale;          // 图片最大放大倍数

    CGFloat _cutWidth;          // 裁剪宽高
    CGFloat _cutBordWidth;      // 裁剪边框宽度
    CGFloat _cutCornerRadius;   //裁剪边框圆角
    UIColor *_cutBordColor;     // 裁剪边框颜色
    UIColor *_cutMaskColor;     // 裁剪遮罩颜色
}

- (void)viewDidLoad {
    [super viewDidLoad];
    _cutCornerRadius = 6;
    _cutBordWidth = 3;
    _cutBordColor = [UIColor whiteColor];
    _cutMaskColor = [[UIColor blackColor] colorWithAlphaComponent:0.7];
    _maxScale = 5;
    _animationTime = 0.3f;
    _cutWidth = 300;

    _viewWeidth = self.view.frame.size.width;
    _viewHeight = self.view.frame.size.height;
    self.view.backgroundColor = [UIColor blackColor];

    [self setupImageView];
    [self addGestureRecognizer];
    [self addmaskView];
    [self addSubBttons];
}

#pragma mark - setup ui
- (void)setupImageView{

    _imageView = [[UIImageView alloc]initWithImage:self.originalImage];
    [self.view addSubview:_imageView];
    _imageView.center = self.view.center;

    CGFloat weidthScale = _imageView.image.size.width / _viewWeidth;
    CGFloat heightScale = _imageView.image.size.height / _viewHeight;

    // 长宽按照比例显示
    CGFloat imgMixW = _cutWidth;
    CGFloat imgMixH = _cutWidth / (_imageView.image.size.width / _imageView.image.size.height);
    _isWideImg = NO;
    if (weidthScale > heightScale) {
        imgMixW = _cutWidth / (_imageView.image.size.height / _imageView.image.size.width);
        imgMixH = _cutWidth;
        _isWideImg = YES;
    }
    _imageView.bounds = CGRectMake(0, 0, imgMixW, imgMixH);
    _imageMinSize = CGSizeMake(imgMixW, imgMixH);

}
- (void)addGestureRecognizer {

    UIPinchGestureRecognizer * pich = [[UIPinchGestureRecognizer alloc]initWithTarget:self action:@selector(pichGestureAction:)];
    [self.view addGestureRecognizer:pich];

    UIPanGestureRecognizer * pan = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(panGestureAction:)];
    [self.view addGestureRecognizer:pan];
}

- (void)addmaskView {

    CGFloat maskX = (_viewWeidth - _cutWidth)/2.0;
    CGFloat maskY = (_viewHeight - _cutWidth)/2.0;
    CGRect maskRect = CGRectMake(maskX, maskY, _cutWidth, _cutWidth);
    _cutRect = maskRect;

    //描边
    CAShapeLayer *borderLayer = [CAShapeLayer layer];
    borderLayer.frame = self.view.bounds;
    borderLayer.lineWidth = _cutBordWidth;
    borderLayer.strokeColor = _cutBordColor.CGColor;
    borderLayer.fillColor = [UIColor clearColor].CGColor;
    
    UIBezierPath *bezierPath=[UIBezierPath bezierPathWithRoundedRect:maskRect
                                                        cornerRadius:_cutCornerRadius];
    borderLayer.path = bezierPath.CGPath;

    self.maskView = [UIView new];
    self.maskView.backgroundColor = [UIColor clearColor];
    self.maskView.frame = self.view.bounds;
    [self.view addSubview:self.maskView];

    [self.maskView.layer insertSublayer:borderLayer atIndex:0];


    {//镂空
        CAShapeLayer *maskLayer = [CAShapeLayer layer];
        maskLayer.frame = self.view.bounds;
        maskLayer.fillColor = _cutMaskColor.CGColor;

        UIBezierPath *bezierPath=[UIBezierPath bezierPathWithRect:self.view.bounds];
        [bezierPath appendPath:[[UIBezierPath bezierPathWithRoundedRect:maskRect cornerRadius:_cutCornerRadius] bezierPathByReversingPath]];
        maskLayer.path = bezierPath.CGPath;

        [self.maskView.layer insertSublayer:maskLayer atIndex:0];
    }
}

- (void)addSubBttons{

    UIButton * cancleButton = [[UIButton alloc]init];
    [self.view addSubview:cancleButton];
    [cancleButton setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
    [cancleButton setTitle:@"取消" forState:UIControlStateNormal];
    cancleButton.frame = CGRectMake(30, _viewHeight-60, 40, 40);
    [cancleButton addTarget:self action:@selector(cancelBtnClick) forControlEvents:UIControlEventTouchUpInside];

    UIButton * tureButton = [[UIButton alloc]init];
    [self.view addSubview:tureButton];
    [tureButton setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
    [tureButton setTitle:@"确定" forState:UIControlStateNormal];
    tureButton.frame = CGRectMake(_viewWeidth -70, _viewHeight-60, 40, 40);
    [tureButton addTarget:self action:@selector(sureBtnClick) forControlEvents:UIControlEventTouchUpInside];

}

#pragma mark - action
- (void)cancelBtnClick {
    [self.navigationController popViewControllerAnimated:YES];
    [self dismissViewControllerAnimated:YES completion:nil];
}
- (void)sureBtnClick {
    UIGraphicsBeginImageContextWithOptions(CGSizeMake(_cutWidth, _cutWidth), YES, [UIScreen mainScreen].scale);

    CGFloat imgX = _imageView.frame.origin.x-(_viewWeidth-_cutWidth)/2;
    CGFloat imgY = _imageView.frame.origin.y - (_viewHeight-_cutWidth)/2;
    CGFloat imgW = _imageView.frame.size.width;
    CGFloat imgH = _imageView.frame.size.height;

    [_imageView.image drawInRect:CGRectMake(imgX, imgY, imgW, imgH)];
    UIImage * tempImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    if (self.complete) {
        self.complete(tempImage);
    }

    [self.navigationController popViewControllerAnimated:YES];
    [self dismissViewControllerAnimated:YES completion:nil];
}
// 手势
- (void)pichGestureAction:(UIPinchGestureRecognizer *)pinch{

    if (pinch.state == UIGestureRecognizerStateBegan || pinch.state == UIGestureRecognizerStateChanged) {
        CGFloat newWidth = _imageView.frame.size.width * pinch.scale;
        CGFloat newHeight = _imageView.frame.size.height * pinch.scale;
        _imageView.bounds = CGRectMake(0, 0, newWidth, newHeight);
        pinch.scale = 1;
    }else if(pinch.state == UIGestureRecognizerStateEnded){

        [self autoScale];

        [self autoTransLationUseRect:_imageView.frame];
    }
}

- (void)panGestureAction:(UIPanGestureRecognizer *)pan{

    if (pan.state == UIGestureRecognizerStateBegan || pan.state == UIGestureRecognizerStateChanged) {

        CGPoint transLationPoint = [pan translationInView:self.view];
        CGFloat newCentX = _imageView.center.x + transLationPoint.x;
        CGFloat newCentY = _imageView.center.y + transLationPoint.y;
        _imageView.center = CGPointMake(newCentX, newCentY);

        [pan setTranslation:CGPointZero inView:self.view.superview];

    }else if(pan.state == UIGestureRecognizerStateEnded){

        [self autoTransLationUseRect:_imageView.frame];
    }
}

// 移动处理
- (void)autoTransLationUseRect:(CGRect)imgFrame {

    CGRect cutRect = self.cutRect;
    // 水平方向
    if (imgFrame.origin.x > cutRect.origin.x) { //左边
        imgFrame.origin.x = cutRect.origin.x;
    }

    if (CGRectGetMaxX(imgFrame) <= CGRectGetMaxX(cutRect)) {   //右边
        imgFrame.origin.x  = CGRectGetMaxX(cutRect) - imgFrame.size.width;
    }

    // 垂直方向
    if (imgFrame.origin.y > cutRect.origin.y) {
        imgFrame.origin.y = cutRect.origin.y;
    }
    if (CGRectGetMaxY(imgFrame) <= CGRectGetMaxY(cutRect)) {
        imgFrame.origin.y = CGRectGetMaxY(cutRect) - imgFrame.size.height;
    }

    if (imgFrame.size.width < cutRect.size.width || imgFrame.size.height < cutRect.size.height) {
        CGPoint center = CGPointMake(cutRect.origin.x+_cutWidth/2, cutRect.origin.y+_cutWidth/2);
        [UIView animateWithDuration:_animationTime animations:^{
            self.imageView.center = center;
        }];
    }else {
        [UIView animateWithDuration:_animationTime animations:^{
            self.imageView.frame = imgFrame;
        }];
    }

}

// 缩放处理,设置了边界。保证内容都在裁剪框里面
- (void)autoScale {
    CGFloat scale = _imageView.frame.size.width / _cutWidth;
    if (_isWideImg) {
        scale = _imageView.frame.size.height / _cutWidth;
    }
    CGFloat imgW = _imageMinSize.width;
    CGFloat imgH = _imageMinSize.height;
    if (scale < 1) {
        [UIView animateWithDuration:_animationTime animations:^{
            self.imageView.bounds = CGRectMake(0, 0,imgW, imgH);
        }];
    }else if(scale > _maxScale){
        imgW = imgW * _maxScale;
        imgH = imgH * _maxScale;
        [UIView animateWithDuration:_animationTime animations:^{
            self.imageView.bounds = CGRectMake(0, 0,imgW, imgH);
        }];
    }
}
@end