My app allows users to view another users info by tapping their avatar, at which they can block that user so that their message content is not visible.
What is the best way when returning to the chat view to clear the messages and reload them?
This would allow my blocking code to work on the fly. Currently it works when I dismiss the chat view and return but not when jump to another view and then back to the chat view.
Ive tried self.collectionView!.reloadData() but that does not do anything.
All you need is to implement
override func viewDidAppear(animated: Bool) {
super.viewDidAppear(animated)
self.collectionView?.reloadData()
}
that is called when you come back from an already instantiated view.
Call the reloadData method after a delay.
self.performSelector(#selector(self.delayReload), withObject: nil, afterDelay: 0.1)
func delayReload() {
self.collectionView.reloadData()
}
Hope this will help you.
Sincerely,
Harri.
Related
I am going to detect the swiping or selecting tab event in XLPagerTabStrip library in Swift 4.
I only need to get the tab index whenever selected tab is changed.
So I have checked library in Github but not found any good solutions.
thanks.
So I didn't find a solution from the library itself but, I used viewWillDisappear and for every time you swipe away of the view this function will be called.
Should be written as follows in your child view controller:
override func viewWillDisappear(_ animated: Bool) {
//Do your thing here
}
You can read more about this callback function here.
You can simply override updateContent
override func updateContent() {
super.updateContent()
// your code ....
}
I am trying to catch doubleClick events from my NSOutlineView to be passed to my ViewController. My idea is to catch doubleClick events and to get the selected row from my OutlineView
What I did so far was subclassing the NSOutlineView in order to overwrite mouseDown
override func mouseDown(with event: NSEvent) {
super.mouseDown(with: event)
if event.clickCount >= 2 {
...
}
}
That works well however I don't know how to pass this event to my ViewController. The ViewController is already implementing the NSOutlineViewDelegate protocol.
I guess that the solution is not far away but somehow I am stuck.
UPDATED
Although you can set up NSGestureRecognizer for single click and NSClickGestureRecognizer for double clicks in OSX, You should probably be using the doubleAction property of the NSOutlineView directly.
Here's an example of how to set it up
This comes from a another of the Wenderlich tutorials, and there is a good discussion on SO already
func checkForRecipes(noRecords: Bool) {
//segue to addNewRecipe page
if noRecords == true{
print("Can't Find any Recipes!")
self.performSegue(withIdentifier: "ToAddNewRecipeVC", sender: self)
}else{
print("error, noRecords not equal to zero")
}
I am able to segue successfully via the storyboard but want to do so programmatically based on information returned from a delegate.
Upon running the app, the information from the delegate is successfully sent to the function "checkForRecipes" -i.e "noRecords" returns TRUE, but for some reason, the below line of code within that function does not seem to execute (and no errors are thrown):
self.performSegue(withIdentifier: "ToAddNewRecipeVC", sender: self)
The app starts up but stops at the main screen, whereas it should segue to the "AddNewRecipe" view controller.
The segue itself definitely has a segue ID of "ToAddNewRecipeVC". I have also tried dispatching to the main queue (to no avail) based on the following thread.
I'm stumped - what's going wrong here?
OK, it looks as though I have solved the problem. I embedded the main view controller into a navigation controller and now everything works as intended. I tried this same tactic earlier and it kept throwing up errors. grrr!
Anyway - thank you to all for the input!
I would like to let the user know when new content is available via the image of a button. Take snapchat for instance: the user is aware of new snaps because the left button turns red (on the mainView). I would like to do the same.
I already processed the notification in the background in
didReceiveRemoteNotification. Thanks to this post, I was able to awake the app in the background when a new APN arrives.
Now I would like to update the image of a button straight from applicationWillEnterForeground. This is the only way that comes to my mind as the view is already loaded when the user clicks on the app (not the banner or the notification center).
Any help would be greatly appreciated. Thank you.
If anybody ever comes across the same problem...
Trying to interact directly with a ViewController from the AppDelegate was obviously a terrible idea. Instead I came across this post that tells me how to know when a ViewController enters the foreground. Here is #nsgulliver answer:
override func viewDidLoad() {
super.viewDidLoad()
NSNotificationCenter.defaultCenter().addObserver(self, selector:"doYourStuff", name:
UIApplicationWillEnterForegroundNotification, object: nil)
}
func doYourStuff(){
// your code
}
Then remove the observer:
deinit {
NSNotificationCenter.defaultCenter().removeObserver(self)
}
I am trying to learn Swift. I currently have a button that plays an animation but I want to have the animation start immediately after the app loads. How would I go about doing that?
You need to put your animation on the viewDidApear method, while will be called after your viewDidLoad method.
For example
override func viewDidAppear(animated: Bool) {
super.viewDidAppear(animated)
UIView.animateWithDuration(2, animations: {
//do what ever here
})
}
Your question is not very specific so I'm not sure if this answers your question.
When your iOS application starts, there is usually a View Controller that gets rendered on the screen as your main entry point. This can be changed in in your AppDelegate.swift
Now, let's assume that in your application, a view controller named WelcomeViewController is the first page and you have your button along with the rest of your logic in it. Every view controller has certain functions that you can override and use. For example:
viewDidLoad
viewDidAppear
viewWillAppear
viewWillDisappear
the names are self-explanatory so I'm sure you can guess what they do. In your case, just override viewDidAppear and start your animation in there.
override func viewDidAppear(animated: Bool) {
...
}