如何制作UICollectionViewCell的動態寬度

Question

我想動態設置UICollectionViewCell的寬度。 我在swift中找到了一些代碼，我想要Objective-C中的代碼。

let flowLayout = collectionViewLayout as! UICollectionViewFlowLayout
    if indexPath.item % 3 == 0 {
        let cellWidth = (CGRectGetWidth(collectionView.frame) - (flowLayout.sectionInset.left + flowLayout.sectionInset.right))
        return CGSize(width: cellWidth, height: cellWidth / 2)
    } else {
        let cellWidth = (CGRectGetWidth(collectionView.frame) - (flowLayout.sectionInset.left + flowLayout.sectionInset.right) - flowLayout.minimumInteritemSpacing) / 2
        return CGSize(width: cellWidth, height: cellWidth)
    }

Answer 1

你可以嘗試這個......

- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath {

    UICollectionViewFlowLayout *flowLayout = (UICollectionViewFlowLayout*) collectionView.collectionViewLayout;

    if (indexPath.item % 3 == 0) {
        float cellWidth = (CGRectGetWidth(collectionView.frame) - (flowLayout.sectionInset.left + flowLayout.sectionInset.right));
        return CGSizeMake(cellWidth, cellWidth / 2);
    } else {
        float cellWidth = (CGRectGetWidth(collectionView.frame) - (flowLayout.sectionInset.left + flowLayout.sectionInset.right) - flowLayout.minimumInteritemSpacing) / 2;
        return CGSizeMake(cellWidth, cellWidth);
    }
}

Answer 2

這是最簡單的解決方案。

你的UIViewController應該實現UICollectionViewDelegateFlowLayout。 然后需要在UIviewController上實現下面的函數。

 func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {

    let width = self.collectionView.frame.size.width / 2;


    return CGSize(width: width, height: 230)

}

此外，您可以在故事板上調整每個單元格的間距值。 單擊collectionView，然后查看大小檢查器。

Answer 3

將單元格的寬度設置為容器視圖的百分比，如：

cell.frame = CGRectMake(x, y, self.view.frame.size.width * 20 / 100, height);

或者您可以使用CollectionView Delegates

- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath {
    return CGSizeMake(self.view.frame.size.width*20/100, 192.f);
}

Answer 4

Swift 2.2

override func collectionView(collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAtIndexPath indexPath: NSIndexPath) -> CGSize {
    var flowLayout = (collectionView.collectionViewLayout as! UICollectionViewFlowLayout)
    if indexPath.item % 3 == 0 {
        var cellWidth: Float = (CGRectGetWidth(collectionView.frame) - (flowLayout.sectionInset.left + flowLayout.sectionInset.right))
        return CGSizeMake(cellWidth, cellWidth / 2)
    }
    else {
        var cellWidth: Float = (CGRectGetWidth(collectionView.frame) - (flowLayout.sectionInset.left + flowLayout.sectionInset.right) - flowLayout.minimumInteritemSpacing) / 2
        return CGSizeMake(cellWidth, cellWidth)
    }
}

Swift 3.0

override func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
    var flowLayout: UICollectionViewFlowLayout? = (collectionView.collectionViewLayout as? UICollectionViewFlowLayout)
    if indexPath.item % 3 == 0 {
        var cellWidth: Float? = (collectionView.frame.width - (flowLayout?.sectionInset?.left + flowLayout?.sectionInset?.right))
        return CGSize(width: CGFloat(cellWidth), height: CGFloat(cellWidth / 2))
    }
    else {
        var cellWidth: Float? = (collectionView.frame.width - (flowLayout?.sectionInset?.left + flowLayout?.sectionInset?.right) - flowLayout?.minimumInteritemSpacing) / 2
        return CGSize(width: CGFloat(cellWidth), height: CGFloat(cellWidth))
    }
}