Mac app disappears when window is closed then another app is selected - swift

I created a new macOS project in Xcode 11.4 where the language is Swift and user interface is SwiftUI. Without making any changes to the code in the project, the app will disappear from the dock by performing the following steps:
launch the Mac app by running the Xcode project
close the main window of the Mac app
select another running app such as Safari
the original Mac app disappears from the dock with no way to access it
This behavior does not happen if the window of the Mac app is open. I can select other running apps then go back to the original Mac app with no problems.

This behavior is known as Automatic Termination. I find it a misfeature, but Apple considers it a feature.
Your app may not have actually quit. It may just appear to have quit. "Launching" it again will just make it reappear in the Dock. It's also possible that some apps which look like they're still running have actually been terminated by the system. In theory, if you try to switch to them, they will be launched and told to restore their previous state to maintain the illusion that they were running all along. In practice, apps (even Apple's) rarely properly restore things to exactly how they were.
The process list in Activity Monitor is a true reflection for what is and is not actually running. Look there to determine if your app has really been terminated.
A developer is supposed to have to opt-in to Automatic Termination because it requires explicit coding of state restoration. However, Xcode's app project/target templates have it enabled by default. You can remove the NSSupportsAutomaticTermination key from your Info.plist to disable it.
Likewise, you'll presumably want to disable Sudden Termination, too, if you're not prepared to support it. You would remove the NSSupportsSuddenTermination key.

Related

Why would my side-loaded Windows Store app go no further than the splash screen?

I have a Windows Store App that, of course, runs fine on my dev machine.
After creating the package to side load for testing, I installed it on another (desktop) machine. Using the instructions for side-loading contained on pages 25 and 26 of Brundritt's free ebook "Location Intelligence for Windows Store Apps", my app seems to install just fine, except that the app is not added to the Windows 8.1 start screen at the end, as expected.
Nevertheless, I can find the app via the Search functionality - I type the name, it shows up in the "found" list (with its logo), but when I try to run it, the splash screen simply "flashes" and then the app disappears. It icon is indeed parked on the taskbar, and every time I click it, the splash screen flashes, but that's all.
This is a Windows 8.1 app that contains a Bing Map, SQLite (and sqlite-net), as well as ExifLib.
It does show up in Task Manager's "App History" tab.
How can I rectify this problem, or at least determine what the problem might be?
UPDATE
This may (or may not be) significant: the version of the app I sideloaded was built in debug mode. Do I need to build in release mode for this to work?
Also: After building in release mode (for the first time) on the dev machine, it no longer finds the SQLite data that had formerly existed. Does changing from debug to release change the path to the database or something?
Does this help? http://blogs.msdn.com/b/vcblog/archive/2012/09/28/10354327.aspx It appears that the app needs to be built in release mode to work properly.

Reset push notification permission setting in ios5

I am developing an app that uses push notifications, and testing on a device with iOS 5.1.1. I would like to test the scenario where the user is prompted about push notifications during the app's first run. The dialog appears the first time I call registerForRemoteNotificationTypes, but never appears again, even if the app is re-installed from scratch. How can I clear the setting so that the dialog will appear again?
The same question was posted before, but the answers do not work for iOS 5 or later, as noted in the comments there.
Apple's documentation says to uninstall the app and mess with the clock to make it look like the app was uninstalled for a day, but this does not work on iOS5.
Another answer suggested running General -> Reset -> Erase All Content And Settings - I tried this, but it froze my device and I ended up having to power-cycle it. In any case, this is a heavy-handed solution that is not practical for testing.
Another answer suggested removing your app's entry from /private/var/mobile/Library/RemoteNotification/Clients.plist, but this file does not exist on iOS5.
Is there a way to accomplish this on iOS5?
I found a solution that works if your device is jailbroken:
Use an app like iFile to open the file /var/mobile/Library/SpringBoard/applicationstate.plist with a property list viewer
Find your app's bundle identifier and delete the key SBRemoteNotificationClient
Restart SpringBoard - either reboot the device, SSH to the device and run killall SpringBoard, or use the Respring app.
Next time you run your app, it will show the notification permission dialog once again.
I've tested this on iOS 5.1.1.
Provided your code paths for iOS 5 and iOS 6 aren't too different, the easiest option is probably to just test that specific behaviour on iOS 6 — the callbacks you get on iOS 5 should be similar enough for it not to be an issue.
Alternatively, change the app's bundle ID. Slightly tedious (in the past I've needed to restart Xcode for it to notice that change in bundle ID), and you'll need a wildcard provisioning profile handy.

iPhone App in suspended state, launched by URL, showing Default.png

The app responds to a custom URL, and correctly launches when in a suspended state. The question is, can I disable showing the Default.png when launched this way?
A use case for clarity:
app is started normally
a home button press puts app in standby
a url of the scheme the app recognizes is tapped in mobile safari
users sees Default.png before launch is complete.
As you probably know, when fast app switching activates usually the app is redisplayed with a screenshot of the last state rather than the Default.png. This is what I'd prefer happens when the URL launch takes place also.
It sounds like what is going on is that Fast App Switching is not actually working. So:
Make sure you are building the application for SDK for OS 4.0. If you don't, you app will not have fast app switching support.
See if fast app switching normally (otherwise) works with your application. I.E. when you just switch to safari, then re-launch your application, do you get the "default.png"?
Run the app under the debugger, but on your actual device. Make the problem happen, go into the Organizer, and look under device logs. This will show you if there was a low-memory issue which caused your application to be terminated, when Safari was launched, thus requiring it to be re-launched when the URL was selected.
I believe there were two mechanisms in place. In my app, I do not support "Launch with URL" - but what I do do is support the Application Delegate's call:
-(BOOL) application:(UIApplication *) application handleOpenURL:(NSURL *) url {
This may be the difference - this is the call which can be made to an application that is running to hand it a URL to process. If you are using the other technique, use this one instead. I use this, and do not see the "default.png" - i.e. do not evoke a "clean relaunch" when I get called.
Here's a possible workaround. This was causing me a headache with trying to seamlessly return from Facebook's single sign on process. I wanted the appearance of going back to my app's login area, instead of the appearance of restarting the app, even though I verified in every way possible that the app was indeed returning from fast app switching and not actually restarting.
While I couldn't find any way to force the app to display the previous state's screenshot, I did discover that the app will display Default-scheme.png (for example, Default-fb12345.png or Default-appname.png) when invoked with a url. So if your post-app switching screenshot is fairly predictable, grab a screenshot from iOS Simulator and copy it into your app. I would consider this an iOS bug. The app should always display the last screenshot when app switching, rather than Default-scheme.png simply because a url is involved.
Another possibility, which I didn't test, would be to symlink the bundle's Default-scheme.png (and Default-scheme#2x.png) to the snapshot file in the app home directory. This would be Library/Caches/Snapshots/[Bundle identifier]/UIApplicationAutomaticSnapshotDefault-Portrait#2x.jpg for most situations (unless it's landscape, or an iPad). If your app's state is unpredictable but the orientation is fixed, this could be a good option to try.
Make sure you've got the "Required Background Modes" key set in the Info.plist to the function that the app needs. If it's not listed, I just use "App Plays Audio" to keep it open.

How to force application Settings bundle get updated?

Application Settings.bundle contains a version number, which is automatically generated during build. From build log I can see that new value is written there, also when looking inside the file itself in MacOS X Finder I see correct updated value.
Settings in iPhone simulator or in real iPhone shows me the old value. Removing application and reinstalling is so far the only way I've managed to get the new updated value visible.
Question: how can I force iPhone Settings application to read my new latest updated bundle file?
Some background info, which might or might not be related: I install application only via Xcode into both simulator and iPhone. Is this the problem? Just found this in Apple docs, not sure what it actually says. Seems to contradict itself (last chapter)...
Each time you reinstall your application, iPhone OS performs a clean install, which deletes any previous preferences. In other words, building or running your application from Xcode always installs a new version, replacing any old contents. To test preference changes between successive executions, you must run your application directly from the simulator interface and not from Xcode.
So Xcode always replaces old content, but to test changes I cannot use Xcode? What was that? Done both (after installation via Xcode) and didn't see new values in settings. Any ideas how does it actually work? Do I always have to make non-Xcode installation?
Try cleaning and building. It seems that xcode caches dates and doesn't notice the change that your script is making. I've had similar things happen, clean always fixes it, but it is indeed a nuisance.
Make sure to shut down the Settings app running in the background on device. It looks like Settings caches settings while it's running - but pulls the updated values when the Settings app is re-launched.
In my case, it seems that my modified root.plist, created/edited via the Xcode property list editor, just wasn't being saved.
There was no problem at all with the Settings Bundle being copied over to the iPad. A quick cmd-S followed by a rebuild and go/debug updated Settings on the iPad straight away - no app uninstall/reinstall even needed. You'd think there'd at least be a haven't-saved-it warning from Xcode, as there always is for code source files.
I just tried this and it worked.
In Xcode go to : Window->Organizer,
then view installed apps on the connected iPad/iPhone, remove the app, then recompile and run your app on the device.
I think the issue has something to do with the iPad's cache.

iPhone Device Debugging

Is it possible to actually use the Xcode debugger when running an iPhone app on the device rather than the simulator? i.e., can I have the device stop at breakpoints that I set in my code and step through the code as it runs on the device?
EDIT: I should mention that I am a registered developer with Apple and have a valid certificate. In fact, I can build and run iPhone applications on my device just fine. However, even in Debug mode, my application will not stop on breakpoints or output to the console when I run it on my device. If it helps, my application will function normally in debug mode (e.g., stopping at breakpoints) when I run in the simulator.
EDIT 2: I've tried resetting my phone, completely removing and reinstalling Xcode, creating a new project, changing all the settings mentioned in the answers on this page (as well as others), cleaning and building my project, Build and Debug... If I click Pause, it says "Error from Debugger: Quit". :( Maybe I'll try to debug on this device using Xcode on another computer and see what happens.
EDIT 3: Well, I tried using another computer using a fresh install of Xcode in a new project, and I still can't get device debugging to work. I have a suspicion that it's my iPhone or cable perhaps? I'd like to think that I'm not so incompetent that I've missed something so embarrassingly obvious, but I've double- and triple-checked all of the suggestions mentioned here.
EDIT 4: FINALLY got device debugging to work. I have a feeling that something low-level on my device was causing issues...nothing I did worked on my system. However, I installed Xcode on another system and device debugging on the same device (with the same cable) worked flawlessly. Directly after that, device debugging began working on my original machine, leading me to believe that some strange hardware flag was screwed up and somehow "reset" on the second machine. In any case, it works now... Thanks for all the help. :)
Also, I'm unsure if it's better to leave this question unanswered or pick the most "helpful" answer...
Yes -- just use a device build. You have to get certificates and provision it.
This is a good description:
http://boga.wordpress.com/2008/07/16/debugging-ipod-provision-profilescertificates/
Make sure to start debugging by pressing "Cmd-Y"... and not "Cmd-R" :-)
You may try last trick in case nothing can help.
If your application launched successful on your device from XCode but did not stop at breakpoints - try press "pause" button after start in debug mode. If you will see application paused properly (do not react to user's action) add new breakpoint then press "run" to continue application execution. In some cases it may helps to stop at new breakpoint.
Yes, just set your project to build for the Device.
If you need to setup debugging for jailbroken iPhone (up to 2.2.1) (not pay 99 to Apple yet) follow next steps:
Install MobileInstallationPatch for your iPhone via Cydia (use Search Tab)
Switch off PROVISIONING_PROFILE at XCode: Go to /Developer/Platforms/iPhoneOS.platform/Info.plist, add next keys:
<key>PROVISIONING_PROFILE_ALLOWED</key>
<string>NO</string>
<key>PROVISIONING_PROFILE_REQUIRED</key>
<string>NO</string>
You may also add these keys to any
project particularly at XCode, Project
Build Settings, User-Defined
variables.
Add key to your project Info.plist at XCode
SignerIdentity = Apple iPhone OS Application Signing
Don't forget to install and add to your project settings self-signing certificate from Apple
http://developer.apple.com/documentation/Security/Conceptual/CodeSigningGuide/Procedures/Procedures.html#//apple_ref/doc/uid/TP40005929-CH4-SW2
"Build and Go", you can connect iPhone and start debugging.
Important! You may need to install and launch at least one legal app (any free one) from App Store first (before "Build and Go" step). Otherwise your application will be successfully installed by XCode to your device but may not be launched. Try this troubleshoot first in case of problem with app launching.
Yes. Debugger and performance tools work fine on the device. That's where I do most of my debugging.
Xcode>preferences>debugging uncheck load symbols lazily
fixed the breakpoints not holding in device problem for me.