如何制作UICollectionViewCell的动态宽度

Question

我想动态设置UICollectionViewCell的宽度。 我在swift中找到了一些代码，我想要Objective-C中的代码。

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

你可以试试这个......

- (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

这是最简单的解决方案。

您的UIViewController应该实现UICollectionViewDelegateFlowLayout。然后，需要在UIviewController上实现以下函数。

 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，您可以调整故事板上每个单元格的间距值。单击collectionView，然后查看大小检查器。

Answer 3

将单元格的宽度设置为容器视图的百分比，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))
    }
}

Answer 5

如果收集视图单元格中有文本，则只需要引用场景中的某个标签而没有宽度限制，然后每次调整项目大小时，只需为其分配文本，然后调用

目标C：

NSString *text = [arrayOfItems objectAtIndex:indexPath.item];
_outletoflbl.text = text;
return CGSizeMake(_outletoflbl.intrinsicContentSize.width + 60, 40);

迅速：

let text = arrayOfItems[indexPath.item]
_outletoflbl.text = text
return CGRect(width:_outletoflbl.intrinsicContentSize.width + 60, height: 40)

键是_outletoflbl，是为其分配文本的标签，以获取最合适的字体和从接口构建器分配的其他属性的宽度！

检查结果：