I have a chat feature in an iOS app. the chat previews are presented in a tableView and I am using a class for the TableView cells themselves. I want to listen for new messages so I can put a "new Message" label on the cells. The relevant parts of the tableView Cell are:
var chat: Chat! {
didSet {
self.updateUI()
self.observeNewMessages()
}
}
extension ChatTableViewCell {
func observeNewMessages() {
let chatMessageIdsRef = chat.ref.child("messageIds")
chatMessageIdsRef.observe(.childAdded, with: { snapshot in
let messageId = snapshot.value as! String
DatabaseReference.messages.reference().child(messageId).observe(.childAdded, with: { snapshot in
//let message = Message(dictionary: snapshot.value as! [String : Any])
print("looks like there is a new message") //works
self.messageLabel.text = "New Message!"
//self.delegate?.newMessage()
})
})
}
}
The print statement is there to test the listener. The problem I am having is when the table view loads and the cells get created, observeNewMessages() is executing the print statement regardless of whether there were new messages. It is just reading the old children that are already there first? Obviously this is going to cause the message label to always read "New Message." I'm not too good with Firebase so is there a better Firebase function to use or a better way to do this?
*I am using 2 queries because the Message dictionary will allow me to see if the current user made the message or not. The delegate is there because my next step will be to reload the tableview -- as it is now, this will also cause an infinite print statement loop...
Related
I am trying to take some events from firebase and add them to a table view for the user to see. My current code looks like this:
For some reason, the events are only showing up when I print them in the closure (ref.child("Events") part), but outside, it is only showing the "hello" I pushed. Please help me fix this issue, preferably with actual code.
You need to reload after the for loop
self.tblEvents.reloadData()
Also put these 2 lines at the beginning of viewDidLoad
self.tblEvents.dataSource = self
self.tblEvents.delegate = self
Please reload your evens table view in view did load after loop like I have done in below code,
ref.child(“Events”).observe(.value, with: { (data) in
let events = data.value as! [String:[String:Any]]
For (_, value) in events {
self.eventsArray.append(value[“EventTitle”]! as! String)
})
// add this line in your code
tblEvents.reloadData()
Situation as it should be
We have a today widget that shows a maximum of 6 buttons depending on data set in the corresponding app. This data is shared using app-groups. If at least one button is configured it will show up as shown in the image above. If the user is not logged in, or if no buttons are configured, it will show a message as shown in the image below.
Problem
After several hours (somewhere between 4 and 7) of not having opened the app, the widget reverts to the 'No buttons configured' view.
Analysis so far
The way the data is loaded from the app-group is done using the code as shown below. (gist for full code) In the way I had written it, the only way the 'No buttons configured' view can be shown is if the buttons array actually exists but has a length of zero.
I expected something like a cache clearing or a background service stopping, but as far as I can see, exceptions should be caught earlier:
If no connection could be made to the app-group data, userDefaults should be nil, so it should show the 'Not logged in view'.
In case the buttons were never defined, buttons should be nil and so again it should show the 'Not logged in view'
Considering the app does nothing in the background, the app itself could not be changing the buttons.
I tried reproducing this while having the debugger connected, but the problem will not reproduce.
Does anyone even have the slightest idea on how to fix this issue or how to start debugging this?
Relevant files:
TodayViewController
Cordova Plugin
Relevant code:
private struct sharedData {
static var baseUrl: String?
static var token: String?
static var phoneDeviceId: String?
static var buttons: Array<Button>?
}
func loadData() {
let groupIdentifier = "group." + NSBundle.mainBundle().bundleIdentifier!
var groupIdArray = groupIdentifier.componentsSeparatedByString(".")
groupIdArray.removeAtIndex(groupIdArray.count - 1)
let appGroupIdentifier = groupIdArray.joinWithSeparator(".");
let userDefaults = NSUserDefaults.init(suiteName: appGroupIdentifier)
if (userDefaults == nil) {
print("Error in user defaults")
setButtonTitle("Not logged in. Open Triggi to continue.")
return false
}
sharedData.baseUrl = userDefaults?.valueForKey("baseUrl") as? String
sharedData.token = userDefaults?.valueForKey("token") as? String
sharedData.phoneDeviceId = userDefaults?.valueForKey("phoneDeviceId") as? String
let buttons = userDefaults?.valueForKey("buttons") as? NSArray
if (sharedData.baseUrl == nil || sharedData.token == nil || sharedData.phoneDeviceId == nil || buttons == nil) {
print("Missing data")
setButtonTitle("Not logged in. Open Triggi to continue.")
return false
}
if (buttons?.count == 0) {
print("No buttons configured")
setButtonTitle("No buttons configured. Open Triggi to continue.")
return false;
}
// More things are done with the data here
}
Today Extension Controller is a UIViewController and thus follows the same lifecycle as that of a UIViewController. So, the lifecycle method viewDidLoad() is called everytime whenever the widget is loaded.
Also, widgetPerformUpdateWithCompletionHandler is called:
when widget is updated in background
before widget snapshot is taken
So, instead of just calling loadData() in widgetPerformUpdateWithCompletionHandler, also call it from viewDidLoad().
Also, where have you written the code to add/remove UIButtons from superview and to show "No buttons configured" in your code?
I am trying to make a search bar, where you can search for users names. The cell is showing two things - and image and a label.
The label is showing the users name and the image is showing the profile picture. The image needs the user userID to display his/her picture.
The countryAndCode contains the users userID called country, and the users name called code.
My problem is that it is adding the first user twice and I do not know why or how to change it.
Here is the relevant code, let me know if you would like to see more:
func startObersvingDB() {
FIRDatabase.database().reference().child("UserInformation").observeEventType(.ChildAdded, withBlock: { snapshot in
let title = snapshot.value!["usersUID"] as? String
let name = snapshot.value!["userName"] as? String
self.tableData.append(title!)
self.tableDataNames.append(name!)
for i in 0..<self.tableData.count {
print(self.tableDataNames.count)
print(self.tableData.count)
self.countryAndCode.append((self.tableData[i], code: self.tableDataNames[i]))//this shows error in XCode some times
//if the above code doesn't compile then use the below code
print("DONE")
print(self.countryAndCode)
}
self.tableView.reloadData()
})
}
I've spent a fun couple of hours trying all sorts of different combinations to have a label properly update its title after a Firebase async download. It's the same issue raised here and here. Seems like a clear fix, but I'm doing something wrong and would appreciate any help pointing me in the right direction.
The basic flow is view loads, data is downloaded from Firebase, some labels are updated accordingly with downloaded data. One representative iteration I have tried is as follows:
// Query Firebase.
let detailsRef = self.ref.child("eventDetails")
detailsRef.queryOrdered(byChild: "UNIQUE_ID_EVENT_NUMBER").queryEqual(toValue: eventID).observeSingleEvent(of: .value, with: { snapshot in
if (snapshot.value is NSNull) {
print("error")
}
else {
var tempDict = [NSDictionary]()
for child in snapshot.children {
let data = child as! FIRDataSnapshot
let dict = data.value as! NSDictionary as! [String:Any]
tempDict.append(dict as NSDictionary)
}
self.dictionaryOfRecoDetails = tempDict
self.ParseFirebaseData()
DispatchQueue.main.async {
// This is the function that updates labels and button text in format like self.websiteLabel.titleLabel?.text = "Appropriate String"
self.loadDataForView()
}
}
})
func loadDataForView() {
// Example of the label update that happens within this function.
// Do not show website button if there is no website.
if self.recommendation.recommendationWebsiteUrl == "" || self.recommendation.recommendationWebsiteUrl == nil || self.recommendation.recommendationWebsiteUrl == "NA" {
self.websiteLabel.titleLabel?.text = ""
self.websiteHeight.constant = 0
self.websiteBottom.constant = 0
}
else {
self.websiteLabel.titleLabel?.text = "Go to Website"
}
}
EDIT UPDATE: The call to the code above is coming from viewDidAppear(). It doesn't update if I call it from viewDidLayoutSubviews() either.
From debugging I know the label update is getting called, but nothing is changing. Feels like something simple I'm missing, but I'm stuck. Thanks for your ideas.
I'm pretty sure you don't need the DispatchQueue.main.async bit. Just try calling self.loadDataFromView() and see if that helps.
This ended up being a lesson in mis-labeling causing confusion. The label being changed actually isn't a label, but a button. Shouldn't have been named websiteLabel! Once the title was changed with self.websiteLabel.setTitle("Go to Website", for: .normal) then everything worked as expected.
In my app each user sets up a profile page and all this info is stored on Parse. When the current user hits a button it segues to a tableViewController that displays in cells all the other users on the app. In each cell there is a button which the user presses to view the full profile page of the user that they have selected. I have a VC set up to hold all the info I just don't know how to display the particular user that the current user has selected into it. How do I single out the chosen users information? I have read the Parse documentation on relational queries but I can't seem to get my head around it. https://parse.com/docs/ios/guide#queries-relational-queries
So in finer detail basically all my users are displaying on a VC. It has name and profile picture, when the user clicks on the info button beside a certain user it should open a new screen and display all of this users information stored on Parse.
I have tried creating a static outside the class
struct Data { var OtherName:String! var id:String! }
And then in my ViewDidLoad:
let query = PFQuery(className: "_User")
// otherQuery.orderByDescending("createdAt")
query.whereKey("username", notEqualTo:PFUser.currentUser()!.username!)
query.findObjectsInBackgroundWithBlock { (users: [AnyObject]?, error: NSError?) -> Void in
if error == nil {
// success
print(users!.count)
for user in users! {
self.imageFiles.append(user["image"] as! PFFile)
self.instrumentText.append(user["instrument"] as! String)
self.nameText.append(user["name"] as! String)
self.ageText.append(user["age"] as! String)
// self.locationText.append(user["location"] as! PFGeoPoint)
var singleData = Data()
singleData.id = user.objectId
singleData.OtherName = user["name"] as! String
print("\(singleData)")
} // users
Then on the VC that the info button segues to I am trying to call it and upload each label with just the user that was selected.
self.userName.text = "" as String
But the "" is staying blank.
Then I was thinking maybe if I add that when the more info button is pressed that the user it was pressed on gets chosen and is added to a chosen string on Parse and then I just have to call the user from the chosen string when I am on the chosen users profile page and call the info that way and then when the user clicks the back button the user is no longer chosen. It just seems like I would be adding and taking away a lot of users to "chosen" in Parse is there a better way?
I am able to display all the users info but how do I just display a chosen user from Parse without using the objectId because at the top of each cell it will return a different user here each time depending on settings previously set on a different VC such as only show users in a certain age bracket etc. I know I must set an Id of some sort on button touched but I am at a complete loss. The only online help out there that I can find is set for other languages eg. https://parse.com/docs/js/guide#users-querying>
So I guess my question is :
1.Does anyone know a tutorial they could point me towards.
2.Does anyone know how I even get started and I can go from there myself.
3.Can anyone help?
*Swift and Parse newbie little to no experience in other languages.
New code in firstVC:
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "userProfileDetailsSegue" {
if let indexPath = resultsPageTableView.indexPathForSelectedRow {
let controller = (segue.destinationViewController) as! UserProfileDetailsViewController
***error here: UserProfileDetailsViewController.userToShowDetail = indexPath.row
//line above is the one I can't get to work it needs to equal to the cell selected?
}
}
}
New Code in destinationVC:
var userToShowDetail: PFUser? {
didSet {
self.configureView()
}
}
func configureView() {
// Update the user interface for the detail item.
if let userToShowDetail: PFUser = self.userToShowDetail {
if let label = self.userName {
nameText.append(userToShowDetail["name"] as! String)
// self.nameText.append(user["name"] as! String)
}
}
}
You're going to need to do a couple of things for this to work. First, in the view controller that you're using to show another user's information, you need to set a property like var userToShowDetail: PFUser?. Then in your view with all of the users of your app, you need to create a segue to bring them from the current view to the detail view. Assuming you're using a TableView, you can connect just one prototype cell to the detail view you're trying to navigate. Then you'll need to override prepareForSegue and set the new view controller's user equal to the user at the row that was selected. I don't know how you're storing your objects of user's of your app, but you should probably be able to do something like this.
override fun prepareForSegue(segue: UIStoryboardSegue) {
if segue.identifer == "segueToShowDetailInfo" {
//get the index path for the row that was selected
let indexPath = self.tableView.indexPathForSelectedRow()
//get the PFUser object for that particular row
let userToShow = self.appUsers[indexPath.row]
//create your new view controller
let newVc = segue.destinationViewController as! DestinationVC
//assign the new vc's property to your object
newVc.userToShowDetail = userToShow
}
}
But in your query, you probably shouldn't have a separate array of the the different parts of the user's data. You should just make one array, call it var appUsers = [PFUser]() and then when you get a user back in your query, just say:
for user in users! {
self.appUsers.append(user) as! PFUser
}
There, now you have a whole array of objects that holds a reference to every user. When someone is using your app, and selects a cell, then you can perform the prepare for segue method as above.
Note that I also noticed you have a didSet on your variable in your new view controller. Calling a function to update the UI after this variable is set will not work, and may crash, because the view controller doesn't have a window yet.