Detect application minimize event for UIKIt for Mac? - swift

When i minimize the application applicationDidEnterInBackground not called for Mac Catalyst. After some search i found that Background delegate methods not called for Mac Catalyst but foreground method of Scene delegate called.
is there any way to track or handle minimize delegate methods like NSWindowDelegate have?
Thanks

Well, if you check NSWindowDelegate.windowWillMiniaturize: you'll notice that its parameter is just a notification (its name is NSWindowWillMiniaturizeNotification).
So, you can simply observe that notification to get notified whenever a window in your app is about to be minimized:
NotificationCenter.default.addObserver(forName: NSWindow.willMiniaturizeNotification, object: nil, queue: nil) { notification in
print("This window is about to be minimized:", notification.object)
}
You can also do the same to get notified about other events like:
NSWindow.didMiniaturizeNotification: After the window is minimized.
NSWindow.didDeminiaturizeNotification: After the window is restored/deminimized.
NSWindow.willEnterFullScreenNotification: Before entering full screen.
NSWindow.didEnterFullScreenNotification: After entering full screen.
NSWindow.willExitFullScreenNotification: Before exiting full screen.
NSWindow.didExitFullScreenNotification: After exiting full screen.
Full list of notifications here.

Related

Quit code for watchOS

In Xcode there is a place to set actions when the interface controller is dismissed in:
override func didDeactivate() {
// This method is called when watch view controller is no longer visible
super.didDeactivate()
}
However, my watchOS app needs to perform an action when the app quits completely i.e. the home screen is visible. Not when the watch is simply lowered and the screen is dimmed because the app is still running as a workout app and is performing actions.
Is there a way to do this?
In ExtensionDelegate, you'll find the method applicationWillResignActive.
Sent when the application is about to move from active to inactive
state. This can occur for certain types of temporary interruptions
(such as an incoming phone call or SMS message) or when the user quits
the application and it begins the transition to the background state.
Use this method to pause ongoing tasks, disable timers, etc.
You can use this method to do what you need.

Keep Cocoa Window Minimized When App Displays NSAlert

I'm having difficulty determining how to keep an application minimized when it's running and it displays an NSAlert.
The short of it is that I have an application that is transferring data, and it displays an NSAlert when it finishes the transfer. If the app is minimized, I want it to remain that way even though it displays the NSAlert.
I call the NSAlert with (in Swift):
alert.beginSheetModalForWindow(self, completionHandler: handler)
But the window unminimizes itself when this code fires. If the window is already not minimized, it doesn't grab focus or do anything unexpected (which is the way I want it).
Is there a way to accomplish this? Thanks!
You can try to delay displaying NSAlert.
Put your alert code in method. When there is a trigger to call this method check if your window is visible. If yes -> call this method. If not -> schedule an NSTimer that will fire after a second and call custom method to check if window is visible (YES -> display alert, NO -> schedule timer again).
FYI: NSAlert when displayed as sheet creates instance of NSPanel which is a subclass of NSWindow.

applicationDidBecomeActive getting called twice

My app delegate method applicationDidBecomeActive: is getting called twice for the first time launch of the application. I have some portion of code which I want to execute only once & that I have put into applicationDidBecomeActive:
What should I do?
I got the issue. I am using Location Services. When launching for the first time after I tap on "OK" on the location services alert, my applicationDidBecomeActive gets called one more time which is the normal iOS behavior.
If you want to call your code only once when app becomes active, try calling it from two methods.
didFinishLaunchingWithOptions
applicationWillEnterForeground
instead of calling it only from applicationDidBecomeActive.
This is because of location or push notification alert.
After the native location/push notification has been dismissed, applicationDidBecomeActive will be called.
I don't know if this will help, but I just had the same issue with a totally simple app that doesn't use Location Services, and I found out it's an illusion. Look at the logging messages I got:
2012-12-22 10:47:45.329 Bizarro[10416:907] start applicationDidBecomeActive:
2012-12-22 10:47:45.333 Bizarro[10416:907] end applicationDidBecomeActive:
2012-12-22 10:47:45.329 Bizarro[10416:907] start applicationDidBecomeActive:
2012-12-22 10:47:45.333 Bizarro[10416:907] end applicationDidBecomeActive:
Look closely. Look at the times. The first and third messages have the same time. The second and fourth messages have the same time. They are the same messages! It's an Xcode bug; it has nothing to do with my code. Xcode is reporting the same log messages twice.
In my case, I was able to prevent this by turning off all Behaviors for Running -> Generates Output.
What about:
Increment on applicationDidBecomeActive
Decrement on callback events of permissions requests or other alerts that trigger another applicationDidBecomeActive when closed.
With Xcode 6 there's a new reason this can happen: when you launch an app in a resizable simulator, applicationDidBecomeActive: will get called twice.
It launches the app with the default size class, and then applies the size you were last using—even if you were using the defaults. Any time a change in size class is applied, applicationDidBecomeActive: gets called.
When app launches first time
it calls sequentially,
didFinishLaunchingWithOptions
applicationDidBecomeActive (Twice)
When we open the Control Center it calls only,
applicationDidBecomeActive
When app come from background to foreground it calls sequentially
applicationWillEnterForeground
applicationDidBecomeActive
I'm currently seeing double notifications.
It's happening because my AppDelegate's init code is being called twice.
It's being called once when the main() does [[NSBundle mainBundle] loadNibNamed:#"MainMenu" owner:application topLevelObjects:&tl] (ie, when the .XIB file is loaded), becaues the .XIB file is setting up FirstResponder to my custom AppDelegate, and then it's being called again when main() calls [[myAppDelegate alloc] init].
The init code is what does the addObserver calls, so two observers are being set up for each notification I care about, which is why my notifications get called twice.
I'm a newbie OS X programmer, so I'm not yet sure of the best way to resolve these two, but wanted to post it here in case it's of help to others, another place to look.
Have you possibly created an instance of your class in Interface Builder AND in your AppDelegate code, perhaps?
If you have code you want called only once when the app starts up, then use
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
instead.
Otherwise, applicationDidBecomeActive will be called whenever your app becomes active again, so that doesn't just mean twice as in your case, but every time the user switches back to your app after switching to another.
If you use RxSwift, then you can just throttle the application event, so it doesn't call twice in the same second:
NotificationCenter.default.rx.notification(Notification.Name.UIApplicationDidBecomeActive)
.throttle(1, scheduler: MainScheduler.instance)
.subscribe { (event) in
self.appEnteredFromBackground()
}.disposed(by: disposeBag)
private func appEnteredFromBackground() {
Analytics.trackPageView(withScreen: .home)
dataStore.checkIfAllowingRides()
}
I put this code in my actual view controller where the logic is supposed to happen on ApplicationDidBecomeActive.
I just check at top of applicationDidBecomeActive: if the request was really sent (I made a function for this, checking status), if so I return already.
The second time in applicationDidBecomeActive:, the function reads the status as Deny or Allowed, because this is after the User answered the Alert.

How do you register for UIApplicationWillEnterForegroundNotification in MonoTouch

I have a problem that the ViewWillAppear method for a UIView does not fire when the application returns from the background. This is a problem, as my main application screen is showing values that are retrieved from the user settings, and if the user has changed these while the application was in the background I need to have the screen refreshed. I have read that one should register for the UIApplicationWillEnterForegroundNotification using NSNotificationCenter.
How do you do this in MonoTouch? Or does anyone know an alternate way of ensuring that the screen is always kept up to date, even when returning from the background?
You could try something along the lines of:
//Register for the notification somewhere in the app
NSNotificationCenter.DefaultCenter.AddObserver(UIApplication.WillEnterForegroundNotification, EnteredForeground);
//snip
void EnteredForeground (NSNotification notification)
{
// do your stuff here
}
Bear in mind you would need to do this for every view controller you'd like to update when enterting from the background!

Deferentiating the push notification handler when application is foreground and background

It is said that (correct me if I'm wrong) if the application is in the foreground we have to handle push notifications in the "didReceiveRemoteNotification" and if the application is in the background using "didFinishLaunchingWithOptions" when user taps the "view" button of the app. As I dont have a phone to test I want to know whether I am handling this properly.
1) What will be invoked when I taps on the "View" button in the push notification?
2) Let say I am running the application in the foreground and push notification receives at the same time. Will I be given the push notification alert? If so what will happen if the user click on the View button?
3) In this thread How to handle push notifications if the application is already running? it says:
"alert" key will not be there directly under the userInfo dictionary, you need to get another dictionary with name "aps" and then get the "alert" or "body" from "aps" dictionary"
Is this true?
4) I need to push to a certain view when the user clicks on the View button. Hence do I need to handle that code in both methods?
Thank you
There's a nice rundown of the methods invoked by a push notification in this Apple vid: http://developer.apple.com/videos/iphone/#video-advanced-pushnotification - make sure you visit download the full version in iTunes.
This direct link might work: http://developer.apple.com/itunes/?destination=adc.apple.com.3391495696.03391495702.3416205190?i=1378617410
Either way, the general idea is that if your app isn't in the foreground, tapping your view button will trigger didFinishLaunchingWithOptions, and if it is the foreground app, you'll get the didReceiveRemoteNotification.
I don't think you'll get the alert. The method didReceiveRemoteNotification will be called, and it'll be up to you to show a UIAlert if you want.
Yes - that's true.
Yes, but I think you can simplify this by creating a third method specifically designed to handle your view. You can call this from both didFinishLaunching (only if it launched via a notification), and didReceiveRemoteNotification. This way, if your app needs to be launched, you can have time to do any other setup you might need to do for the app to work right out of the get-go (load saved data, init tabbar controllers or anything else like that).
Best of luck