In the manifest we have fours dangerous runtime permissions from two groups.
<!-- Required to read and write to shredPref file. -->
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<!-- Required to get location of device. -->
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
In the activity where the permissions are required. Note it is important to check for permissions in any activity that requires permissions, as the permissions can be revoked while the app is in the background and the app will then crash.
final private int REQUEST_CODE_ASK_MULTIPLE_PERMISSIONS = 124;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.act_layout);
// A simple check of whether runtime permissions need to be managed
if (Build.VERSION.SDK_INT >= 23) {
checkMultiplePermissions();
}
We only need to ask for permission for one of these from each group and all other permissions from this group are granted unless the permission is revoked by the user.
private void checkMultiplePermissions() {
if (Build.VERSION.SDK_INT >= 23) {
List<String> permissionsNeeded = new ArrayList<String>();
List<String> permissionsList = new ArrayList<String>();
if (!addPermission(permissionsList, android.Manifest.permission.ACCESS_FINE_LOCATION)) {
permissionsNeeded.add("GPS");
}
if (!addPermission(permissionsList, android.Manifest.permission.READ_EXTERNAL_STORAGE)) {
permissionsNeeded.add("Read Storage");
}
if (permissionsList.size() > 0) {
requestPermissions(permissionsList.toArray(new String[permissionsList.size()]),
REQUEST_CODE_ASK_MULTIPLE_PERMISSIONS);
return;
}
}
}
private boolean addPermission(List<String> permissionsList, String permission) {
if (Build.VERSION.SDK_INT >= 23)
if (checkSelfPermission(permission) != PackageManager.PERMISSION_GRANTED) {
permissionsList.add(permission);
// Check for Rationale Option
if (!shouldShowRequestPermissionRationale(permission))
return false;
}
return true;
}
This deals with the result of the user allowing or not allowing permissions. In this example, if the permissions are not allowed, the app is killed.
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
switch (requestCode) {
case REQUEST_CODE_ASK_MULTIPLE_PERMISSIONS: {
Map<String, Integer> perms = new HashMap<String, Integer>();
// Initial
perms.put(android.Manifest.permission.ACCESS_FINE_LOCATION, PackageManager.PERMISSION_GRANTED);
perms.put(android.Manifest.permission.READ_EXTERNAL_STORAGE, PackageManager.PERMISSION_GRANTED);
// Fill with results
for (int i = 0; i < permissions.length; i++)
perms.put(permissions[i], grantResults[i]);
if (perms.get(android.Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED
&& perms.get(android.Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED) {
// All Permissions Granted
return;
} else {
// Permission Denied
if (Build.VERSION.SDK_INT >= 23) {
Toast.makeText(
getApplicationContext(),
"My App cannot run without Location and Storage " +
"Permissions.\nRelaunch My App or allow permissions" +
" in Applications Settings",
Toast.LENGTH_LONG).show();
finish();
}
}
}
break;
default:
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
}
}
More Information https://inthecheesefactory.com/blog/things-you-need-to-know-about-android-m-permission-developer-edition/en