I have my storyboard set up such that
Tab bar controller -> nav bar controller 1, nav bar controller 2 -> CollectionView controller 1, CollectionView controller 2
The content inside my collectionviews are basically database i get from firebase (which is working fine). It's just when I start up my app, I can't see the cells in the first collectionview but I can see the cells in my second collectionview. Also, I added a print statement and a segue when you click on a cell and this actually works on both collectionviews. I just can't see the content (just a label) of my collectionviewcell in the first collectionview (the first tab item).
This is the code for my first tab bar item
import Foundation
import UIKit
import Firebase
class SaleListViewController: UIViewController, UICollectionViewDataSource, UICollectionViewDelegate {
let rootref = FIRDatabase.database().reference()
let storage = FIRStorage.storage()
var item_names = [String]()
var item_image_urls = [String]()
var item_details = [Dictionary<String, String>]()
var group = DispatchGroup()
var processRunning = false
@IBOutlet weak var collectionView: UICollectionView!
override func viewDidLoad() {
super.viewDidLoad()
self.load_data()
}
/**
Call the firebase function
*/
func load_data(){
self.group.enter()
self.processRunning = true
get_firebase_data(){
if(self.processRunning){
self.processRunning = false
self.group.leave()
}
}
self.group.notify(queue: DispatchQueue.main, execute: {
print("done")
})
}
/**
Get data from firebase database
- parameter completionHandler: Function to be called once it's finished
*/
func get_firebase_data(completionHandler: () -> ()){
rootref.child("Sale").observe(.value, with: { (snapshot) in
if(snapshot.exists()){
var item_data = snapshot.value! as! Dictionary<String, AnyObject>
for(type_2_container,item_list) in item_data{
for(uid_container, item_detail_container) in item_list as! Dictionary<String, AnyObject>{
for(uid, item_detail) in item_detail_container as! Dictionary<String, AnyObject>{
var item_detail_dict = item_detail as? Dictionary<String,String>
var item_detail_temp = Dictionary<String, String>()
for key in (item_detail_dict?.keys)!{
item_detail_temp[key] = item_detail_dict?[key]
}
item_detail_temp["user_id"] = uid
self.item_details.append(item_detail_temp)
if(!self.item_names.contains(item_detail_dict!["item_name"]!)){
self.item_names.append(item_detail_dict!["item_name"]!)
self.item_image_urls.append(item_detail_dict!["item_image"]!)
}
}
}
}
print(self.item_details)
self.collectionView?.reloadData()
print("data was reloaded")
}
})
completionHandler()
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return self.item_details.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell:SellcollectViewCellController = collectionView.dequeueReusableCell(withReuseIdentifier: "CellSale", for: indexPath) as! SellcollectViewCellController
cell.cell_name_sale.text = self.item_details[indexPath.row]["item_name"]
print(cell.cell_name_sale.text)
return cell
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
print("selected")
self.performSegue(withIdentifier: "toDetail", sender: self.item_details[indexPath.row])
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if(segue.identifier == "toDetail"){
let nextVC = segue.destination as! ShowDetailsViewController
let item_details = sender as! Dictionary<String, String>
nextVC.item_details = item_details
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
/**
Signs out a user when the button linked with the IBAction is clicked.
- parameter sender: Object that sent the action message
*/
@IBAction func log_out(_ sender: Any) {
do{
try! FIRAuth.auth()!.signOut()
self.performSegue(withIdentifier: "logout", sender: nil)
print("user logged out!")
} catch {
print("error")
}
}
}
And this is my second tab bar item
import Foundation
import UIKit
import Firebase
class BuyListViewController: UIViewController,UICollectionViewDataSource, UICollectionViewDelegate {
let rootref = FIRDatabase.database().reference()
let storage = FIRStorage.storage()
var item_names = [String]()
var item_image_urls = [String]()
var item_details = [Dictionary<String, String>]()
var group = DispatchGroup()
var processRunning = false
@IBOutlet weak var collectionView: UICollectionView!
override func viewDidLoad() {
super.viewDidLoad()
self.load_data()
}
func load_data(){
self.group.enter()
self.processRunning = true
get_firebase_data(){
if(self.processRunning){
self.processRunning = false
self.group.leave()
}
}
self.group.notify(queue: DispatchQueue.main, execute: {
print("done")
})
}
func get_firebase_data(completionHandler: () -> ()){
rootref.child("Buy").observe(.value, with: { (snapshot) in
print("inside buy firebase")
if(snapshot.exists()){
var item_data = snapshot.value! as! Dictionary<String, AnyObject>
for(type_2_container,item_list) in item_data{
for(uid_container, item_detail_container) in item_list as! Dictionary<String, AnyObject>{
for(uid, item_detail) in item_detail_container as! Dictionary<String, AnyObject>{
var item_detail_dict = item_detail as? Dictionary<String,String>
var item_detail_temp = Dictionary<String, String>()
for key in (item_detail_dict?.keys)!{
item_detail_temp[key] = item_detail_dict?[key]
}
item_detail_temp["user_id"] = uid
self.item_details.append(item_detail_temp)
if(!self.item_names.contains(item_detail_dict!["item_name"]!)){
self.item_names.append(item_detail_dict!["item_name"]!)
self.item_image_urls.append(item_detail_dict!["item_image"]!)
}
}
}
}
print(self.item_details)
self.collectionView?.reloadData()
print("data was reloaded")
}
})
completionHandler()
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return self.item_details.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell:BuycollectViewCellController = collectionView.dequeueReusableCell(withReuseIdentifier: "CellBuy", for: indexPath) as! BuycollectViewCellController
cell.cell_name_buy.text = self.item_details[indexPath.row]["item_name"]
print(cell.cell_name_buy.text)
return cell
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
print("selected")
self.performSegue(withIdentifier: "toDetail", sender: self.item_details[indexPath.row])
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if(segue.identifier == "toDetail"){
let nextVC = segue.destination as! ShowDetailsViewController
let item_details = sender as! Dictionary<String, String>
nextVC.item_details = item_details
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
@IBAction func log_out(_ sender: Any) {
do{
try! FIRAuth.auth()!.signOut()
self.performSegue(withIdentifier: "logout", sender: nil)
print("user logged out!")
} catch {
print("error")
}
}
}
This is my custom collection view cell controller for the first tab item
import UIKit
class SellcollectViewCellController: UICollectionViewCell {
@IBOutlet weak var cell_name_sale: UILabel!
}
This is the second collection view cell controller
import UIKit
class BuycollectViewCellController: UICollectionViewCell {
@IBOutlet weak var cell_name_buy: UILabel!
}
This is a screenshot of my tab bar controller with the two tab items
