Marshmallow and above Permissions : Runtime Crash

Question

i have a problem with Run time permissions, i tried to manage them for Marshmallow and above but my application still crashes on runtime (not when i restart app) this is the code of activity:

in the Manifest:

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />

Here the activity code ( not all but necessary to understand i think)

 public class HomeActivityNew extends AppCompatActivity implements AdapterView.OnItemClickListener, View.OnClickListener, SeekBar.OnSeekBarChangeListener {

    // here all variables ...
        private boolean permissionToRecordAccepted = false;
        private boolean permissionToWriteAccepted = false;
        private String[] permissions = {"android.permission.RECORD_AUDIO", "android.permission.WRITE_EXTERNAL_STORAGE"}


       @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_home_new);

            int requestCode = 200;
            if (Build.VERSION.SDK_INT >= 23) {
                requestPermissions(permissions, requestCode);
            }

            init();
            myHandler = new Handler();
            slidingUpPanelLayout.setPanelState(SlidingUpPanelLayout.PanelState.HIDDEN);
            SetupToolbar();
            SetupPager();
            SetupDrawer();
            iv_playpause.setTag("pause");



            MobileAds.initialize(getApplicationContext(), getResources().getString(R.string.admov_id));
            AdView mAdView = (AdView) findViewById(R.id.adView);
            AdRequest adRequest = new AdRequest.Builder().build();
            mAdView.loadAd(adRequest);


          /*  SharedPreferences pref = getSharedPreferences("logincheck", Context.MODE_PRIVATE);
            SharedPreferences.Editor edit1 = pref.edit();
            edit1.putString("login","true");
            edit1.apply();*/

        }


        @Override
        public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
            super.onRequestPermissionsResult(requestCode, permissions, grantResults);
            switch (requestCode) {
                case 200:
                    if(grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED){
                        permissionToRecordAccepted=true;
                    }
                    if(grantResults.length > 0 && grantResults[1] == PackageManager.PERMISSION_GRANTED){
                        permissionToWriteAccepted=true;
                    }

                    break;
            }
            if (!permissionToRecordAccepted) HomeActivityNew.super.finish();
            if (!permissionToWriteAccepted) HomeActivityNew.super.finish();
        }

and this the error :

java.lang.RuntimeException: Failure delivering result ResultInfo{who=@android:requestPermissions:, request=200, result=0, data=null} to activity {com.mypackage.HomeActivityNew}: java.lang.

Caused by: java.lang.ArrayIndexOutOfBoundsException: length=0; index=0

variable grantResults empty! app on runtime shows the dialog window for permission and crashes at same time but when i restart the app it waits for permissions

Answer 1

this.requestPermissions should not be called in onCreate. The documentation on requestPermission states:

This method may start an activity allowing the user to choose which permissions to grant and which to reject. Hence, you should be prepared that your activity may be paused and resumed. Further, granting some permissions may require a restart of you application. In such a case, the system will recreate the activity stack before delivering the result to onRequestPermissionsResult(int, String[], int[]).

When checking whether you have a permission you should use checkSelfPermission(String).

Calling this API for permissions already granted to your app would show UI to the user to decide whether the app can still hold these permissions. This can be useful if the way your app uses data guarded by the permissions changes significantly.

Implicit in these statements is that requestPermissions relies upon the Activity Life Cycle. So, your activity needs to be able to handle Pause and Resume and even Re-Start being triggered while requesting permissions. So, wait until your activity is fully set up (call requestPermissions later in onCreate, or in a later callback).

Better yet, you are approaching this wrong. According to Android Documentation - Requesting Permissions

Note: Beginning with Android 6.0 (API level 23), users can revoke permissions from any app at any time, even if the app targets a lower API level. You should test your app to verify that it behaves properly when it's missing a needed permission, regardless of what API level your app targets.

(emphasis mine).

If you kill your activity because it is missing a permission, you are creating an awful user experience. Instant app closure and no reason given is confusing to say the least. And, even if it did grant permission, the user can revoke them at any time.

You should be calling AppCompat.requestPermissions(thisActivity, permissions, requestCode) and you should not be calling it in onCreate (where the activity is not fully initialized).

Furthermore, you should only be calling it if your App does not have permissions granted already. So you should be calling ActivityCompat.checkSelfPermission at the point your App needs the permission.

Failing that, it should ask for the permission it needs. In doing so, it should check if rationale should be displayed (for when the user has denied the permission in the past or revoked permission at some point). Here is an excerpt from googlesamples/android-runtime-permissions

private void requestCameraPermission() {
    Log.i(TAG, "CAMERA permission has NOT been granted. Requesting permission.");

    // BEGIN_INCLUDE(camera_permission_request)
    if (ActivityCompat.shouldShowRequestPermissionRationale(this,
            Manifest.permission.CAMERA)) {
        // Provide an additional rationale to the user if the permission was not granted
        // and the user would benefit from additional context for the use of the permission.
        // For example if the user has previously denied the permission.
        Log.i(TAG,
                "Displaying camera permission rationale to provide additional context.");
        Snackbar.make(mLayout, R.string.permission_camera_rationale,
                Snackbar.LENGTH_INDEFINITE)
                .setAction(R.string.ok, new View.OnClickListener() {
                    @Override
                    public void onClick(View view) {
                        ActivityCompat.requestPermissions(MainActivity.this,
                                new String[]{Manifest.permission.CAMERA},
                                REQUEST_CAMERA);
                    }
                })
                .show();
    } else {

        // Camera permission has not been granted yet. Request it directly.
        ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA},
                REQUEST_CAMERA);
    }
    // END_INCLUDE(camera_permission_request)
}

See the rest of the sample (line above) to see how requesting permissions is typically done. There are other ways to write the code to get other behaviors, but you should first start with a proven and working example, and understand the reasons for each call, before going off in a new direction.

(Developer Samples - Runtime Permissions is is the v7 re-implementation of the sample above. I recommend you review both to understand how permissions work. Be careful, though, not to make incompatible v4 and v7 calls, which can lead to frustrating bugs)

Let me re-emphasize: the user can revoke permissions at anytime, even when the platform/sdk is less than api 23. So, you must check permissions whenever the permission is needed.

Answer 2

Write like this

private String[] permissions = {Manifest.permission.RECORD_AUDIO, Manifest.permission.WRITE_EXTERNAL_STORAGE}

insted of

private String[] permissions = {"android.permission.RECORD_AUDIO", "android.permission.WRITE_EXTERNAL_STORAGE"}

Answer 3

In your code you have used

if (Build.VERSION.SDK_INT >= 23) {
  requestPermissions(permissions, requestCode);//Call require API level 23 and above          
} 

so you have not mentioned else case where you should have requested the permission for API level 23 or low.So corrected code:

 if(Build.VERSION.SDK_INT > Build.VERSION_CODES.M){
     //Call this method for API level 21 and above
  requestPermissions(new String[]{Manifest.permission.RECORD_AUDIO},200);
    }else{
      ActivityCompat.requestPermissions(this,new String[]{Manifest.permission.RECORD_AUDIO},200);
     }