Android 6.0 multiple permissions

Question

I know that Android 6.0 has new permissions and I know I can call them with something like this

if (ContextCompat.checkSelfPermission(this, Manifest.permiss         


        

Answer 1

My approach is based on Nicks' answer and hopefully is a bit more usable for multiple (as many as needed, not only two) permissions. It suggests adding single-responsibility PermissionsHelper class:

import android.app.Activity;
import android.app.AlertDialog;
import android.content.pm.PackageManager;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.util.Log;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class PermissionsHelper {

private static final int REQUEST_ID_MULTIPLE_PERMISSIONS = 100; // any code you want.

public void checkAndRequestPermissions(Activity activity, String... permissions) {
    List listPermissionsNeeded = new ArrayList<>();
    for (String permission : permissions) {
        if (ContextCompat.checkSelfPermission(activity, permission) != PackageManager.PERMISSION_GRANTED) {
            listPermissionsNeeded.add(permission);
        }
    }
    if (!listPermissionsNeeded.isEmpty()) {
        ActivityCompat.requestPermissions(activity, listPermissionsNeeded.toArray(new String[listPermissionsNeeded.size()]), REQUEST_ID_MULTIPLE_PERMISSIONS);
    }
}

public void onRequestPermissionsResult(Activity activity, int requestCode, String permissions[], int[] grantResults) {
    switch (requestCode) {
        case REQUEST_ID_MULTIPLE_PERMISSIONS: {
            Map perms = new HashMap<>();

            for (String permission : permissions) {
                perms.put(permission, PackageManager.PERMISSION_GRANTED);
            }

            if (grantResults.length > 0) {
                for (int i = 0; i < permissions.length; i++)
                    perms.put(permissions[i], grantResults[i]);

                boolean allPermissionsGranted = true;
                for (String permission1 : permissions) {
                    allPermissionsGranted = allPermissionsGranted && (perms.get(permission1) == PackageManager.PERMISSION_GRANTED);
                }

                if (allPermissionsGranted) {
                    Log.d(PermissionsHelper.class.getSimpleName(), "onRequestPermissionsResult: all permissions granted");
                } else {
                    for (String permission2 : perms.keySet())
                        if (perms.get(permission2) == PackageManager.PERMISSION_GRANTED)
                            perms.remove(permission2);

                    StringBuilder message = new StringBuilder("The app has not been granted permissions:\n\n");
                    for (String permission : perms.keySet()) {
                        message.append(permission);
                        message.append("\n");
                    }
                    message.append("\nHence, it cannot function properly." +
                            "\nPlease consider granting it this permission in phone Settings.");

                    AlertDialog.Builder builder = new AlertDialog.Builder(activity);
                    builder.setTitle(R.string.permission_required)
                            .setMessage(message)
                            .setPositiveButton(android.R.string.ok, (dialog, id) -> dialog.cancel());
                    AlertDialog alert = builder.create();
                    alert.show();
                }
            }
        }
    }
}

}

If one or several required permissions have not been granted by user, the detailed AlertDialog message will be shown to him.

Example of usage in Activity:

private PermissionsHelper permissionsHelper;

@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    checkPermissions();

    //any other code
}

@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    permissionsHelper.onRequestPermissionsResult(this, requestCode, permissions, grantResults);
}

private void checkPermissions() {
    permissionsHelper = new PermissionsHelper();
    permissionsHelper.checkAndRequestPermissions(this,
            Manifest.permission.READ_EXTERNAL_STORAGE,
            Manifest.permission.ACCESS_FINE_LOCATION,
            Manifest.permission.ACCESS_COARSE_LOCATION);
}

Hope that this will be useful for someone.