關于UIScrollView中UIImageView的圖檔縮放問題

回看以前的代碼 發現自己在還沒有接觸UIGestureRecognizer時就實作過UIScrollView中UIImageView的縮放 發現UIScrollView有一個代理方法可以實作

核心代碼:

@interface ViewController ()<UIScrollViewDelegate>

@property(nonatomic, strong) UIScrollView *mainScrollView;

@property(nonatomic, strong) UIImageView *mainImageView;

@end

- (UIScrollView *)mainScrollView{
    if(_mainScrollView == nil){
        _mainScrollView = [UIScrollView new];
        _mainScrollView.delegate = self;
    }
    return _mainScrollView;
}

- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView{
    return self.mainImageView;
}
           

隻要實作代理方法 并傳回UIScrollView中的UIImageView 就可以實作圖檔的縮放了