使用带有缩放功能的uicollectionview显示图像[关闭]

Question

我想使用集合视图显示一些图像。我在滚动视图中使用单元格内的滚动视图和图像视图。图像放大和缩小。当单元格被重用时，新的单元格滚动视图和图像视图大小与缩放的旧单元格相同。 当单元格重用滚动视图大小得到默认值时想要。 如何解决这个问题。

Answer 1

@hello 您必须在 Imageview 中设置手势并使用以下方法， 您可以使用手势轻松设置放大和缩小

在 ViewDID..

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view.

 scrollViewMain.maximumZoomScale = 5.0;
    scrollViewMain.minimumZoomScale = 1.0;
    scrollViewMain.clipsToBounds = NO;
    scrollViewMain.delegate = self;
UITapGestureRecognizer *tapTwice = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapTwice:)];
    // set number of taps required
    tapTwice.numberOfTapsRequired = 2;

    // now add the gesture recogniser to a view
    // this will be the view that recognises the gesture
    [scrollViewMain addGestureRecognizer:tapTwice];
}
//------For Zoom IN ScrollView-------------------------------------------------------
-(UIView *)viewForZoomingInScrollView:(UIScrollView *)inScroll {
    //self.iPickedPicture.center = ivPicture.center;
    return _imgView;
}


- (void)tapOnce:(UIGestureRecognizer *)gesture
    {
        //on a single  tap, call zoomToRect in UIScrollView
        if ([scrollViewMain zoomScale] > 1.0)
        {
        float newScale = 1.0;
        CGRect zoomRect = [self zoomToCenter:newScale withCenter:[gesture locationInView:scrollViewMain]];
        [scrollViewMain zoomToRect:zoomRect animated:YES];
        }
        else
        {
            float newScale =  3.5;
            CGRect zoomRect = [self zoomToCenter:newScale withCenter:[gesture locationInView:scrollViewMain]];
            [scrollViewMain zoomToRect:zoomRect animated:YES];

        }
    }
    - (void)tapTwice:(UIGestureRecognizer *)gesture
    {
        //on a double tap, call zoomToRect in UIScrollView
        if ([scrollViewMain zoomScale] == 1.0) {

        float newScale = [scrollViewMain zoomScale] * 3.5;
        CGRect zoomRect = [self zoomToCenter:newScale withCenter:[gesture locationInView:scrollViewMain]];
        [scrollViewMain zoomToRect:zoomRect animated:YES];
        }else
        {
            float newScale = 1.0;
            CGRect zoomRect = [self zoomToCenter:newScale withCenter:[gesture locationInView:scrollViewMain]];
            [scrollViewMain zoomToRect:zoomRect animated:YES];
        }

    }

    - (CGRect)zoomToCenter:(float)scale withCenter:(CGPoint)center {

        CGRect zoomRect;
        zoomRect.size.height = scrollViewMain.frame.size.height / scale;
        zoomRect.size.width  = scrollViewMain.frame.size.width  / scale;

        zoomRect.origin.x = center.x - (zoomRect.size.width  / 2.0);
        zoomRect.origin.y = center.y - (zoomRect.size.height / 2.0);

        return zoomRect;


    }