Scroll View in UITableViewCell won't save position

问题

I have some UIScrollViews in my UITableView.

My problem is that if I scroll the scroll view in the first cell to another position, the fourth cell will also be at that same position.

Same for the second and the fifth, the third and the sixth...

Is there a way for the scroll views in the cells to keep their position?

回答1:

You should save the actual content offsets of your UIScrollViews in an array, retreive the value after a scroll happened in a custom delegate and set the offset to the saved value in cellForRowAt.

CustomCell.swift

weak var delegate: CellScrollViewDelegate?
let scrollView: UIScrollView!
var contentOffset: CGPoint!

func setUpCell() {
    scrollView.delegate = self
    scrollView.contentOffset = savedContentOffset
}


[...]

func scrollViewDidScroll(_ scrollView: UIScrollView) {
    delegate?.horizontalCellDidScroll(indexPath: indexPath, contentOffset: scrollView.contentOffset)
}

TableViewController.swift

var cellScrollContentOffsets = [[CGPoint]]()

func horizontalCellDidScroll(indexPath: IndexPath, contentOffset: CGPoint) {
    cellScrollContentOffsets[indexPath.section][indexPath.row] = contentOffset
}

override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCell(withIdentifier: "CellID", for: indexPath)
    cell.delegate = self
    cell.savedContentOffset = cellScrollContentOffsets[indexPath.section][indexPath.row]
    cell.setUpCell()

    return cell
}

Delegate.swift

protocol CellScrollViewDelegate: class {
    func horizontalCellDidScroll(indexPath: IndexPath, contentOffset: CGPoint)
}

来源：https://stackoverflow.com/questions/45439663/scroll-view-in-uitableviewcell-wont-save-position

标签

ios

swift

uitableview

uicollectionviewcell