shutting down android functionality like qs tiles, volume panel and navigation's

Question

I am working on an well-being app that shuts your phone up for a given period of time (eg. 30min, 1hr, 1.5hr)

In this state user can only see a screen with remaining time on it and cannot

• Access QS tiles
• Access Volume panel
• Navigate out of the Activity

something similar to Oneplus Zen mode

things i have thought of for doing this

• Killing the SystemUI process.(by doing so the QS and volume panel would be dealt with most probably, maybe need root for that tho? also SystemUI automatically restarts itself, quite stubborn)

• Making app a launcher Dynamically?(technically you can't navigate out of a launcher and on reboot you come back to it)

how can I get around accomplishing this? any ideas?

Answer 1

Making application the default launcher of the phone is more practical solution to what you're trying to achieve. I've done this previously in a Flutter application which was going to be installed on kiosk devices to get orders from customers and it worked perfectly. It's a bit tricky to make it work and there's lots of things to do. Here is a list of things I did back then:

1. Use FLAG_SHOW_WHEN_LOCKED flag to the window to bypass the lock screen.

2. Inside of onResume add FLAG_FULLSCREEN flags to hide the status bar.

3. Make your MainActivity launcher by adding LAUNCHER category to in AndroidManifest.xml. Also you can add other attributes I used (Search for them if you don't know what are they supposed to do).

   <activity
       android:name=".MainActivity"
       android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
       android:excludeFromRecents="true"
       android:hardwareAccelerated="true"
       android:launchMode="singleInstance"
       android:showOnLockScreen="true"
       android:showWhenLocked="true"
       android:theme="@style/LaunchTheme"
       android:turnScreenOn="true"
       android:windowSoftInputMode="adjustResize">
       <intent-filter>
           <action android:name="android.intent.action.MAIN" />
   
           <category android:name="android.intent.category.LAUNCHER" />
           <category android:name="android.intent.category.HOME" />
           <category android:name="android.intent.category.DEFAULT" />
       </intent-filter>
   </activity>
   

4. Listen for window focus changes in your MainActivity and bring your application to front if it lost the focus.

   private fun moveToFront() {
     val closeDialog = Intent(Intent.ACTION_CLOSE_SYSTEM_DIALOGS)
     sendBroadcast(closeDialog)
     (activity.applicationContext.getSystemService(Context.ACTIVITY_SERVICE) as ActivityManager)
             .moveTaskToFront(activity.taskId, ActivityManager.MOVE_TASK_WITH_HOME)
     window.setFlags(
           WindowManager.LayoutParams.FLAG_FULLSCREEN,
           WindowManager.LayoutParams.FLAG_FULLSCREEN);
   }
   
   override fun onWindowFocusChanged(hasFocus: Boolean) {
     super.onWindowFocusChanged(hasFocus)
     if (!hasFocus) {
       moveToFront()
     }
   }
   

5. I was also checking if my application is the default launcher.

   private fun isAppDefault(): Boolean {
     val intent = Intent(Intent.ACTION_MAIN)
     intent.addCategory(Intent.CATEGORY_HOME)
     val res: ResolveInfo = packageManager.resolveActivity(intent, 0)
     return res.activityInfo != null && (packageName
           == res.activityInfo.packageName)
   }
   

6. And you're gonna need to communicate between Flutter and the platform using MethodChannel to enable and disable force mode and get the state of the application.