Question

我有一个collectionView，想要使中心单元格比其他单元格大，并且当移至上一个或下一个单元格时，使其中心位置更大

func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    if collectionView == self.collectionView {
        return slidData.count
    } else {
        return categoryData.count
    }
}

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    if collectionView == self.collectionView {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "imageCell", for: indexPath) as! SliderImgCell

        cell.categoryName.text = slidData[indexPath.row].imageTitle
        cell.detail.text = slidData[indexPath.row].imageContent
        cell.pics = slidData[indexPath.item]

        return cell
    } else{
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "categoryCell", for: indexPath) as! CategoryCell

        cell.categoryName.text = categoryData[indexPath.row].depName
        cell.pics = categoryData[indexPath.item]

        return cell
    }
}

Answer 1

您需要这样保存所选的indexPath：

func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
    selectedIndexPath = indexPath 
}

您的集合视图必须确认UICollectionViewDelegateFlowLayout。然后在sizeForItemAt方法中调整单元格的大小：

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
    if indexPath == selectedIndexPath {
        return CGSize(width: 200, height: 90)
    } else {
        return CGSize(width: 180, height: 80)
    }
}

Answer 2

基本上，您需要轮播动画。

看看this库并充分利用它或从代码中寻求帮助。

Answer 3

您可以使用ScrollViewDidScroll(_:)方法来实现，找到中心单元格并将其放大。如果您想了解详细信息，请在下面的代码中写清楚的注释，以查看有关此内容的文章：

https://medium.com/@sh.soheytizadeh/zoom-uicollectionview-centered-cell-swift-5-e63cad9bcd49

func setFocusedCellStyle(_ scrollView: UIScrollView) {
        guard scrollView is UICollectionView else { return }
        // get the centerPoint
        let centerPoint = CGPoint(x: self.collectionView.frame.size.width / 2 + scrollView.contentOffset.x, y: self.collectionView.frame.size.height / 2 + scrollView.contentOffset.y)
        // get the indexPath for the cell at center
        if let indexPath = self.collectionView.indexPathForItem(at: centerPoint), self.centerCell == nil {
            // centerCell is instance variable of type: YourCell
            self.centerCell = (self.colorPickerCollectionView.cellForItem(at: indexPath) as! CustomCollectionViewCell)

            UIView.animate(withDuration: 0.2) {
                // Choose desired scale value
                self.transform = CGAffineTransform(scaleX: 1.58, y: 1.58)
            }
        }

        if let cell = self.centerCell { // center cell is global variable
            let offsetX = centerPoint.x - cell.center.x // get to current position of the cell
            // when cell is 15 pixels away from the center to the sides
            // reset the cell size.
            if offsetX < -15 || offsetX > 15 {
                UIView.animate(withDuration: 0.2) {
                     self.transform = CGAffineTransform.identity
                }
                self.centerCell = nil // set this to nil so next cell in the center will enter the above scope
            }
        }
    }

使CollectionView Cell水平单元格比其他单元格大

3 个答案: