ios - 自动调整 Tableview 单元格到单元格内容(SWIFT)

Question

我正在尝试让我的 tableview 正常工作，因此当单击一个单元格时，它会自动调整大小以适合单元格内的内容。 (不同数量的文字会自动调整大小不同。

Cell when not clicked (first state and size it should go back to when clicked = 44.0

因此对于此图像，这是每个单元格将仅处于默认和取消选择状态的阶段。白色文本将是唯一可见的内容。

Cell clicked state. resizes to my "let selectedCellHeight: CGFloat = 88.0" constant. Which needs to automatically size to fit the green text no matter how much is in there.

这是我的 tableview 和 viewcontroller 的完整代码。

import UIKit

class TasksViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {

@IBOutlet weak var tblTasks: UITableView!

//For persisting data
let defaults = UserDefaults.standard


override func viewDidLoad() {
    super.viewDidLoad()



    self.tblTasks.backgroundColor = UIColor(red: 64/255.0, green: 67/255.0, blue: 68/255.0, alpha: 0)


    self.tblTasks.reloadData()
    self.tblTasks.register(UINib(nibName: "WhiteTaskTableViewCell", bundle: nil), forCellReuseIdentifier: "nameCell")
    tblTasks.tableFooterView = UIView()

    let darkModeColor = UIColor(red: 52/255.0, green: 55/255.0, blue: 55/255.0, alpha: 1.0)
    view.backgroundColor = darkModeColor


    tblTasks.dataSource = self;

    // Do any additional setup after loading the view.
}



override func viewWillAppear(_ animated: Bool) {
    self.tblTasks.reloadData()
}



override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}


func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int{
    return taskMgr.tasks.count

}



//Define how our cells look - 2 lines a heading and a subtitle
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell{


    let identifier = "nameCell"
    var cell: WhiteTaskTableViewCell! = tableView.dequeueReusableCell(withIdentifier: identifier) as? WhiteTaskTableViewCell

    if cell == nil {
        tableView.register(UINib(nibName: "WhiteTaskTableViewCell", bundle: nil), forCellReuseIdentifier: identifier)
        cell = tableView.dequeueReusableCell(withIdentifier: identifier) as? WhiteTaskTableViewCell
    }


    //        Assign the contents of our var "items" to the textLabel of each cell
    //        cell.textLabel!.text = taskMgr.tasks[indexPath.row].name
    //        cell.detailTextLabel!.text = taskMgr.tasks[indexPath.row].desc

    cell.TaskNameLabel.text = taskMgr.tasks[indexPath.row].name
    cell.NotesLabel.text = taskMgr.tasks[indexPath.row].note

    cell.selectionStyle = .none



    return cell

}



func numberOfSections(in tableView: UITableView) -> Int {
        // #warning Incomplete implementation, return the number of sections
        return 1
}



   func tableView(_ willDisplayforRowAttableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
    cell.backgroundColor = UIColor(red: 64/255.0, green: 67/255.0, blue: 68/255.0, alpha: 0)
}



func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCellEditingStyle, forRowAt indexPath: IndexPath) {
    if (editingStyle == UITableViewCellEditingStyle.delete) {
        // handle delete (by removing the data from your array and updating the tableview)

        taskMgr.removeTask(indexPath.row)
        tblTasks.reloadData()
    }
}



   // EXPAND CELL ON CLICK


// Global Variables/Constants

var selectedCellIndexPath: NSIndexPath?

let selectedCellHeight: CGFloat = 88.0
let unselectedCellHeight: CGFloat = 44.0

 func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {

    self.tblTasks.rowHeight = UITableViewAutomaticDimension

    if selectedCellIndexPath == indexPath as NSIndexPath?  {
        return selectedCellHeight
    }
    return unselectedCellHeight
}



 func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    if selectedCellIndexPath != nil && selectedCellIndexPath == indexPath as NSIndexPath? {
        selectedCellIndexPath = nil
    } else {
        selectedCellIndexPath = indexPath as NSIndexPath?
    }

    tableView.beginUpdates()
    tableView.endUpdates()

    if selectedCellIndexPath != nil {
        // This ensures, that the cell is fully visible once expanded
        tableView.scrollToRow(at: indexPath as IndexPath, at: .none, animated: true)
    }
}

/*
// MARK: - Navigation

// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    // Get the new view controller using segue.destinationViewController.
    // Pass the selected object to the new view controller.
}
*/


}

我乐于接受任何帮助和见解。非常感谢。

Answer 1

您需要为您的 UITableView 设置一个 Outlet，并将 rowHeight 参数设置为 UITableViewAutomaticDimension。您还需要将 estimatedRowHeight 设置为适合您需要的值。这样 Cell 的大小将适合其内容的大小。

@IBOutlet weak var tableView: UITableView!

override func viewDidLoad() {
      super.viewDidLoad()        
      tableView.estimatedRowHeight = 55
      tableView.rowHeight = UITableViewAutomaticDimension
}

为此，您需要为单元格的每个元素设置自动布局约束。

Source Apple Doc :

Working with Self-Sizing Table View Cells

In iOS, you can use Auto Layout to define the height of a table view cell; however, the feature is not enabled by default.

Normally, a cell’s height is determined by the table view delegate’s tableView:heightForRowAtIndexPath: method. To enable self-sizing table view cells, you must set the table view’s rowHeight property to UITableViewAutomaticDimension. You must also assign a value to the estimatedRowHeight property. As soon as both of these properties are set, the system uses Auto Layout to calculate the row’s actual height.

Additionally, try to make the estimated row height as accurate as possible. The system calculates items such as the scroll bar heights based on these estimates. The more accurate the estimates, the more seamless the user experience becomes.