Im implementing touch ID to "unlock" my app, and im not sure if ive run into an apple bug or something i need to handle myself. If i tap the Home button and minimize my app before evaluatePolicy can load the Touch ID prompt, it appears over the home screen.
![not enough reputation to display screenshot, so heres a link]https://www.dropbox.com/s/zrhc60lx87ze7mt/IMG_0016.PNG
Successful/failure/cancel evaluation of this policy does nothing, but when i re-enter the app and cancel it again, touchID seems to be disabled forever until i restart the phone.
Anyone else running into this issue or have an ideas?
P.S. Theres an open radar where errSecUserCanceled is never returned from a cancel button tap, so right now i fall into my errSecAuthFailed case, which could also be the cause.
Answer is no. It should not be be displayed, when minimized.
The problem is IMHO that the code segment is being called again from your app when it goes to the background. For example loadView , didLoad and so on.
Try moving the code, that calls the authentication somewhere else in the program (different method).
For example, if your code uses a textView to enter password, you can implement the authentication within keyboardWillShow or similar.
Hope it helps.
Related
First of all I'd like to say sorry in case my question is dummy, I'm really new to iOS and what to understand how thing are going on. Imagine such a situation - user taps on home button and the app starts to collapse, but immediately after taping on home button user taped on some UI element. So, I'm wondering how the iOS will handle this? I tried to do some tests using breakpoints, but since it just test I can't be 100% sure. It seems that if the UI interaction event will happen before the system will call willResignActive then the event will be fully processed and if the system will call willResignActive first, then the even will be discarded and won't be handled at all. Is this correct, or I missed something? Thanks
First, why do you want to use this in your app? If a user presses a button exactly in this time, it's okay that the action is not handled.
The only thing you have to keep track of is that whenever the button gets pressed and let's say you store a file without a completion handler it could be that you present an alert which is saying that everything went well but you actually not saved the file because the user left the app in this time.
But since you're never doing critical actions without completion handlers, in my opinion, there's no need to make sure that this doesn't happen.
If I got you wrong, just comment!
My request for photo library permissions prompt is supposed to pop up as soon as the app is launched. I have set up my info.plist with the library permission.
I have tried both adding/removing the requestAuthorization(_:) function in my AppDelegate.swift in various lifecycle functions.
Current output: The app launches and stays on the launchscreen. When i click on the home button the app minimizes and the permissions prompt appears(as though it was lingering in the background). On allowing permission everything launches as expected.
Desired output: The app launches and the photo library permissions prompt appears on top(as it should). On click of which everything runs as usual.
I can attach pictures if this is not descriptive enough. Also there is no pertaining code as i have removed the requestAuthorization(_:) function(cuz not required). Any tip would go a long way as I have been fiddling with this for days now trying to get this fixed. Thank you!
Your request call should be in the view controller (i.e. viewDidAppear), not the AppDelegate. Having the call in the app delegate is probably causing it to fire at an inappropriate time.
is it possible to prevent the app from closing when my app asks for a fingerprint and the user presses the home button instead of only let the finger rest? I know and understand that it shouldn't be possible everywhere else, but it would be nice if the app wouldn't close when asking for the fingerprint.
It is not ever possible to change regular system behaviour, even though some users might press too hard and go back home that is the behaviour that everyone expects, want to go home, press the home button and it always works
This is not possible, what you are trying to do is getting out of the scope of your application and change the behavior of the device. Apple won't allow it, ever.
They might change the behavior if they think it's better to handle it like that, you can send them a message. But they'll probably never do that as they are killing Touch ID for the sake of Face ID.
I'm developing an app on iOS 7 with a desired feature is that
When I home button, app enter background, I will add an image to current UIWindow. So when app enter background, if user double home button on iOS 7, os will show a small screenshot of current view of my app, so user can see my added image. :) (I did it)
When user return my app by clicking app icon, I want to remove this image immediately. In this situation, "immediately" means that user can NOT see this image anymore, user just see his/her current view when app enter foreground. I try to place the code remove image on the beginning of applicationWillEnterForeground delegate, but I'm still able to see this image for a short time after it disappears.
I also try to set hidden, alpha property for this imageview first, then removeFromSuperview, but it not works.
Can anyone help me to remove it "immediately" as my desire.
That is done automatically for all applications, you don't need to do anything in you code.
I don't think that you can do it faster, it depends of device performance. Sorry man.
Like other says it is really tricky how iOS handles these events. I've been researching and depends on the memory state of the device to do it faster or not. Indeed, in iPhone 4 and 4S may not show the image that you added on applicationWillEnterForeground method.
If I were you I would solve it by adding a smooth fade out animation of that image when the app becomes active again. With [UIView animateWithDuration: animations:] it could be nicely done! :)
If I find out something else I'll answer here!
My app must sometimes show an UIAlertView when the Home button or the locking button is pushed or when the notification center is shown.
I show the Alert from the applicationWillResignActive delegate's method and everything is ok when home button is pushed or when notificacion center is shown. But there is a problem if the button which is pushed is the locking button (on/off button).
In that case, the Alert is not shown when I return to the app (if I used the Home button it is there). I don't do anything else in other AppDelegate methods which are executed. Also, then, when I show a new Alert (any Alert in the app) the Alert which hasn't been shown when I returned is shown after I dismiss the new one.
Please, could anybody help me?
Thanks in advance.
THE EASY, GIVE ME REP ANSWER:
When the app is put into the background, the app is suspended. Part of this process is closing open alert views.
THE I ACTUALLY KNOW WHAT I'M TALKING ABOUT ANSWER:
The logic behind this is that when the user hits the home button when an alert is displayed, they might be going to look for information on how to answer the alert. However, when the sleep button is pressed, the user has stopped using the device altogether. Apple knows that if they unlock thier device again 3 hours later and see something like Confirm Deletion, they will have absolutely no idea what they were just doing and what to do now.
This is known to cause a serious condition known as what-in-the-world-am-I-supposed-to-do-now-itis. Symptoms of this condition include hitting the round button at the bottom of the screen and subsequently holding on your app icon until it jiggles. They then hit the little 'x' button. This is not good for developer's pockets.