Notify UITable from an other Thread - ios

Question

I've got a simple UITable implementation and an array which is called fruits. Taken out of this example. The only difference is that I am using a UIViewController for the UITable insted of a UITableViewController, but this should be irrelevant for now.
class MainViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
var fruits : [String] = Array()
let thread : GetDataForFruitsArrayThread
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return fruits.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "LabelCell", for: indexPath)
cell.textLabel?.text = fruits[indexPath.row]
return cell
}
}
Now I have got a viewDidLoad function in this class also. In the function I am calling a thread which is getting the array as a parameter. The thread is filling up the array with new values asynchronously. Means I don't know if there will be any values or when do the value appear and are set into the array. So you can imagine what I want to ask on this point: How do I signal the UITableView that I have changed the content of the array once the view has loaded the array into the UITable. In c# there is the NotifyAll() function which notfies all the Listener to an attribute. Is there an easy and performant way to do this in swift, optionally without importing any non-included libraries?
override func viewDidLoad() {
super.viewDidLoad()
self.thread = GetDataForFruitsArrayThread(array: &fruits)
self.thread.StartAsynchronously()
}
EDIT - adding GetDataForFruitsArrayThread
class GetDataForFruitsArrayThread : MyThread {
var array : [String]
init(array: inout [String] ) {
self.array = array
}
override func main() {
// init socket
while(true){
_ = withUnsafeMutablePointer(to: &rcvaddr){
$0.withMemoryRebound(to: sockaddr.self, capacity: 1){
recvfrom(m_socket, &pData, bufferlength, 0, UnsafeMutablePointer($0),
&socketAddressLength)
}
}
var fruit = String(cString:inet_ntoa(rcvaddr.sin_addr), encoding: .ascii)
self.array.append(fruit)
}
}
}
EDIT - 21.11.2017:
Following Sandeep Bhandari's answer I changed the following code in the ViewController:
#IBOutlet weak var tableView1: UITableView!
var fruits : [String] = Array() {
didSet {
self.tableView1.reloadData()
}
}
PROBLEM: I am setting a breakpoint at array.append(fruit) in the GetDataForFruitsArrayThread-class. After that there is a breakpoint in the didSet method. But this breakpoint does not get called after the append()-call! NOTE: The parameter on the init function of the GetDataForFruitsArrayThread-class is an in-out parameter!
UPDATE: I found out that if I do the array.append(fruit)-call on the GetDataForFruitsArrayThread.array in the GetDataForFruitsArrayThread-thread, the Fruits-array in ViewController-class does not get changed, therefore didSet did not get called. How can I change this behaviour?

Answer 1

Because you said you are running a endless process to keep updating your array and you want the UI update once the array changes you can use the below solution.
var fruits : [String] = Array() {
didSet {
self.tableView.reloadData()
}
}
What am I doing ? Simple added a setter to array and whenever value changes I reload the tableView.
EDIT:
The above solution will work only if you modify the inout fruits array you pass to GetDataForFruitsArrayThread
self.thread = GetDataForFruitsArrayThread(array: &fruits)
So don't create one more array property in GetDataForFruitsArrayThread rather directly modify the array passed to GetDataForFruitsArrayThread.