Programmatically added UITableView won't populate data - ios

Question

I wish to create UITableView and a custom cell, and add them to my UIViewController.
If I layout UITableView from the storyboard onto my UIViewController, everything works fine with custom cell.
But I realized that animation regarding its height is not very smooth - sometimes the table view disappears
So I decided to create/destroy a UITableView everytime I wish to do some animation, and add it as a subview to my UIViewController.
But the programmatically-added UITableView won't populate data.
What am I doing wrong here?
import UIKit
class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
var dataArr = [String]() // Holds data for UITableView
var tv: UITableView! // Notice it's not #Outlet
override func viewDidLoad() {
super.viewDidLoad()
dataArr = ["one", "two", "three"]
// Create and add UITableView as drop down
tv = UITableView()
tv.delegate = self
tv.dataSource = self
createTableView()
}
func createTableView() {
let w = UIScreen.mainScreen().bounds.size.width
tv.frame = CGRectMake(0, 50, w, 0)
tv.rowHeight = 25.0
// Register custom cell
var nib = UINib(nibName: "searchCell", bundle: nil)
tv.registerNib(nib, forCellReuseIdentifier: "searchCell")
self.view.addSubview(tv)
UIView.animateWithDuration(0.2, delay: 0.0, options: UIViewAnimationOptions.BeginFromCurrentState, animations: {
self.tv.frame.size.height = 100
}, completion: { (didFinish) in
self.tv.reloadData()
})
}
func destroyTableView() {
UIView.animateWithDuration(0.2, animations:
{
// Hide
self.tv.frame.size.height = 0
}, completion: { (didFinish) in
self.tv.removeFromSuperview()
})
}
// MARK: - UITableView
func numberOfSectionsInTableView(tableView: UITableView) -> Int {
return 1
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return dataArr.count
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell: SearchCell = self.tv.dequeueReusableCellWithIdentifier("searchCell") as! SearchCell
cell.cellLabel.text = dataArr[indexPath.row]
return cell;
}
}

Answer 1

I think the problem is with this line.
self.tv.frame.size.height = 100
Try setting the whole frame instead of just the height. Pretty sure a UIView's Frame's properties are read only.
See here
If that doesn't work. Maybe try implementing
func tableView(_ tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat