问题

Goal

I want to create a custom view that has a UITableView as a subview.

The custom view creates the table view programmatically. To the outside world (i.e., the ViewController), though, the custom view itself would appear to be a table view.

What I've tried

import UIKit
class CustomTableView: UIView {
    
    // Do I make outlets?
    //@IBOutlet var dataSource: UITableViewDataSource?
    //@IBOutlet var delegate: UITableViewDelegate?
    
    required init(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
    }
    
    override init(frame: CGRect){
        super.init(frame: frame)
    }
    
    override func awakeFromNib() {
        super.awakeFromNib()
    }
    
    override func layoutSubviews() {
        super.layoutSubviews()
        
        var tableView: UITableView!
        tableView = UITableView(frame: self.bounds)
        // I'm not sure how to set the delegate and dataSource
        // tableView.dataSource = ???
        // tableView.delegate = ???
        
        self.addSubview(tableView)
       
    }
}

After creating the UITableView programmatically and adding it as a subview to the custom view parent, I can't figure out how to get the custom view to act like it is the table view. That is, I don't know how to get the custom view to do the communication between the View Controller and the table view for the delegate and dataSource.

What I've read

Designing Your Data Source and Delegate
Create a static UITableView without Storyboards

These articles seemed good, but I got a little lost.

How do I make the custom view act like it's own table subview with regard to delegate and data source?

回答1:

The solution is to make the tableView a property of the custom class (as @BaseZen suggested). Then provide properties and methods in the custom class to mimic and pass along the properties and methods needed from tableView.

import UIKit
@IBDesignable class UICustomTableView: UIView {

    private var myTableView: UITableView

    required init(coder aDecoder: NSCoder) {
        myTableView = UITableView()
        super.init(coder: aDecoder)
    }
    override init(frame: CGRect){
        myTableView = UITableView()
        super.init(frame: frame)
    }
    override func awakeFromNib() {
        super.awakeFromNib()
    }

    // TODO: @IBOutlet still can't be set in IB
    @IBOutlet weak var delegate: UITableViewDelegate? {
        get {
            return myTableView.delegate
        }
        set {
            myTableView.delegate = newValue
        }
    }

    // TODO: @IBOutlet still can't be set in IB
    @IBOutlet weak var dataSource: UITableViewDataSource? {
        get {
            return myTableView.dataSource
        }
        set {
            myTableView.dataSource = newValue
        }
    }

    func registerClass(cellClass: AnyClass?, forCellReuseIdentifier identifier: String) {
        myTableView.registerClass(cellClass, forCellReuseIdentifier: identifier)
    }

    func dequeueReusableCellWithIdentifier(identifier: String) -> UITableViewCell? {
        return myTableView.dequeueReusableCellWithIdentifier(identifier)
    }

    override func layoutSubviews() {
        super.layoutSubviews()

        // ...

        // setup UITableView
        myTableView.frame = self.bounds
        self.addSubview(myTableView)

        // ...
    }       
}

Then it can be used like a normal UITableView:

import UIKit
class TableViewDemoVC: UIViewController, UITableViewDelegate, UITableViewDataSource {

    @IBOutlet weak var customTableView: UICustomTableView!

    var items: [String] = ["One", "Two", "Three"]

    override func viewDidLoad() {
        super.viewDidLoad()

        // setup the table view from the IB reference
        customTableView.delegate = self
        customTableView.dataSource = self
        customTableView.registerClass(UITableViewCell.self, forCellReuseIdentifier: "cell")

    }

    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

        let cell: UITableViewCell = self.customTableView.dequeueReusableCellWithIdentifier("cell") as UITableViewCell!
        cell.textLabel?.text = self.items[indexPath.row]            
        return cell
    }

    // ...
}

回答2:

It's not the most elegant, but jump out a level:

class MyCustomViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
    override func viewDidLoad() {
        myCustomView = CustomTableView()
        myCustomView.frame = ... /* layout programatically */
        /* Alternatively to the above 2 lines, 
           lay out myCustomView in StoryBoard,
           and capture it as an @IBOutlet. It will then be ready here
           to muck with, well before it gets displayed and needs the data */
        myCustomView.tableView.delegate = self
        myCustomView.tableView.dataSource = self
    }

    /* Now implement all your dataSource and delegate methods */
}

* IMPORTANT *

The key that you're missing is that tableView must be a stored property of your custom view. It's important and needs to be promoted from a silly local! It should also be initialized in the awakeFromNib() function, even if you don't know the frame size. Then reset its frame at layout time.

At a higher level, I don't know "What You're Really Trying To Do." It may not actually be the right implementation technique to be embedding a UITableView within a custom view; consider just laying out the UITableView in the main view. Then if you need decoration around it, lay those out as separate views in StoryBoard.

来源：https://stackoverflow.com/questions/31688938/how-to-embed-a-uitableview-in-a-custom-view

标签

ios