Question

UITableView具有方法rectForRowAtIndexPath:，但在UICollectionView中不存在。我正在寻找一种很好的干净方法来获取单元格的边界矩形，也许我可以在UICollectionView上添加一个类别。

Answer 1

我发现这样做的最好方法如下：

UICollectionViewLayoutAttributes *attributes = [self.collectionView layoutAttributesForItemAtIndexPath:indexPath];

然后，您可以通过attributes.frame或attributes.center

访问该位置

Answer 2

只需要两行代码即可获得完美的框架：

Objective-C

UICollectionViewLayoutAttributes * theAttributes = [collectionView layoutAttributesForItemAtIndexPath:indexPath];

CGRect cellFrameInSuperview = [collectionView convertRect:theAttributes.frame toView:[collectionView superview]];

Swift 4.2

let theAttributes = collectionView.layoutAttributesForItem(at: indexPath)
let cellFrameInSuperview = collectionView.convert(theAttributes.frame, to: collectionView.superview)

Answer 3

在swift 3中

 let theAttributes:UICollectionViewLayoutAttributes! = collectionView.layoutAttributesForItem(at: indexPath)
 let cellFrameInSuperview:CGRect!  = collectionView.convert(theAttributes.frame, to: collectionView.superview)

Answer 4

你可以在swift中做到：

//for any cell in collectionView
let rect = self.collectionViewLayout.layoutAttributesForItemAtIndexPath(clIndexPath).frame

//if you only need for visible cells
let rect = cellForItemAtIndexPath(indexPath)?.frame

Answer 5

怎么样

-(CGRect)rectForCellatIndexPath:(NSIndexPath *)indexPath {

    UICollectionViewCell *cell = [self cellForItemAtIndexPath:indexPath];

    if (!cell) {
        return CGRectZero;
    }

    return cell.frame;

}

作为UICollectionView上的类别？

#import <UIKit/UIKit.h>

@interface UICollectionView (CellFrame)

-(CGRect)rectForCellatIndexPath:(NSIndexPath *)indexPath;

@end


#import "UICollectionView+CellFrame.h"

@implementation UICollectionView (CellFrame)

-(CGRect)rectForCellatIndexPath:(NSIndexPath *)indexPath {

    UICollectionViewCell *cell = [self cellForItemAtIndexPath:indexPath];

    if (!cell) {
        return CGRectZero;
    }

    return cell.frame;

}

@end

如何获取UICollectionViewCell的矩形？

5 个答案: