ios - 展开和折叠表格 View 单元格

Question

我可以展开和折叠单元格，但我想调用 UITableViewCell 中的函数(展开和折叠)来更改按钮标题。

import UIKitclass MyTicketsTableViewController: UITableViewController {    var selectedIndexPath: NSIndexPath?    var extraHeight: CGFloat = 100    override func viewDidLoad() {        super.viewDidLoad()    }    override func didReceiveMemoryWarning() {        super.didReceiveMemoryWarning()        // Dispose of any resources that can be recreated.    }    override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {        return 5    }    override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {        let cell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath) as! MyTicketsTableViewCell        return cell    }    override func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {        if(selectedIndexPath != nil && indexPath.compare(selectedIndexPath!) == NSComparisonResult.OrderedSame) {            return 230 + extraHeight        }        return 230.0    }    override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {        if(selectedIndexPath == indexPath) {            selectedIndexPath = nil        } else {            selectedIndexPath = indexPath        }        tableView.beginUpdates()        tableView.endUpdates()    }}

import UIKitclass MyTicketsTableViewCell: UITableViewCell {    @IBOutlet weak var expandButton: ExpandButton!    @IBOutlet weak var detailsHeightConstraint: NSLayoutConstraint!    var defaultHeight: CGFloat!    override func awakeFromNib() {        super.awakeFromNib()        defaultHeight = detailsHeightConstraint.constant        expandButton.button.setTitle("TAP FOR DETAILS", forState: .Normal)        detailsHeightConstraint.constant = 30    }    func expand() {        UIView.animateWithDuration(0.3, delay: 0.0, options: .CurveLinear, animations: {            self.expandButton.arrowImage.transform = CGAffineTransformMakeRotation(CGFloat(M_PI * 0.99))            self.detailsHeightConstraint.constant = self.defaultHeight            self.layoutIfNeeded()            }, completion: { finished in                self.expandButton.button.setTitle("CLOSE", forState: .Normal)        })    }    func collapse() {        UIView.animateWithDuration(0.3, delay: 0.0, options: .CurveLinear, animations: {            self.expandButton.arrowImage.transform = CGAffineTransformMakeRotation(CGFloat(M_PI * 0.0))            self.detailsHeightConstraint.constant = CGFloat(30.0)            self.layoutIfNeeded()            }, completion: { finished in                self.expandButton.button.setTitle("TAP FOR DETAILS", forState: .Normal)        })    }}

Answer 1

如果您希望单元格在物理上变得更大，那么在您存储 IndexPath 的地方，在 heightForRow: 中使用:

override func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
    if selectedIndexPath == indexPath {
      return 230 + extraHeight
    }
    return 230.0
}

然后当你想在 didSelectRow 中扩展一个时:

selectedIndexPath = indexPath
tableView.beginUpdates
tableView.endUpdates

编辑

这将使单元格动画自己变大，你不需要单元格中的额外动画 block 。

编辑2

 override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
        if(selectedIndexPath == indexPath) {
          selectedIndexPath = nil

          if let cell = tableView.cellForRowAtIndexPath(indexPath) as? MyTicketsTableViewCell {
            cell.collapse()
          }
          if let cell = tableView.cellForRowAtIndexPath(NSIndexPath(forRow:indexPath.row+1, section: indexPath.section) as? MyTicketsTableViewCell {
            cell.collapse()
          }
        } else {
          selectedIndexPath = indexPath

          if let cell = tableView.cellForRowAtIndexPath(indexPath) as? MyTicketsTableViewCell {
              cell.expand()
          }

          if let cell = tableView.cellForRowAtIndexPath(NSIndexPath(forRow:indexPath.row+1, section: indexPath.section) as? MyTicketsTableViewCell {
             cell.expand()
          }
        }

        tableView.beginUpdates()
        tableView.endUpdates()
    }