Assent
Assent is designed to make Marshmallow's runtime permissions easier to use. Have the flexibility of request permissions and receiving results through callback interfaces.
Table of Contents
- Gradle Dependency
- Basics
- Without AssentActivity
- Without AssentFragment
- Using PermissionResultSet
- Fragments
- Duplicate and Simultaneous Requests
- AfterPermissionResult Annotation
Gradle Dependency
The Gradle dependency is available via jCenter. jCenter is the default Maven repository used by Android Studio.
Dependency
Add this to your module's build.gradle file:
dependencies {
// ... other dependencies
compile 'com.afollestad:assent:0.2.5'
}
--
Basics
Note: you need to have needed permissions in your AndroidManifest.xml too, otherwise Android will always deny them, even on Marshmallow.
Activities
The first way to use this library is to have Activities which request permissions extend AssentActivity. AssentActivity will handle some dirty work internally, so all that you have to do is use the requestPermissions method:
public class MainActivity extends AssentActivity {
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (!Assent.isPermissionGranted(Assent.WRITE_EXTERNAL_STORAGE)) {
// The if statement checks if the permission has already been granted before
Assent.requestPermissions(new AssentCallback() {
@Override
public void onPermissionResult(PermissionResultSet result) {
// Permission granted or denied
}
}
, 69, Assent.WRITE_EXTERNAL_STORAGE);
}
}
}
requestPermissions has 3 parameters: a callback, a request code, and a list of permissions. You can pass multiple permissions in your request like this:
Assent.requestPermissions(callback,
requestCode,
Assent.WRITE_EXTERNAL_STORAGE, Assent.ACCESS_FINE_LOCATION);
Fragments
If you use Fragment's in your app, it's recommended that they extend AssentFragment. They will update Context references in Assent, and handle Fragment permission results for you. Relying on the Fragment's Activity can lead to occasional problems.
public class MainFragment extends AssentFragment {
// Use Assent the same way you would in an Activity
}
Without AssentActivity
If you don't want to extend AssentActivity, you can use some of Assent's other methods in order to mimic the behavior:
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Updates the activity when the Activity is first created
// That way you can request permissions from within onCreate()
Assent.setActivity(this, this);
if (!Assent.isPermissionGranted(Assent.WRITE_EXTERNAL_STORAGE)) {
// The if statement checks if the permission has already been granted before
Assent.requestPermissions(new AssentCallback() {
@Override
public void onPermissionResult(PermissionResultSet result) {
// Permission granted or denied
}
}
, 69, Assent.WRITE_EXTERNAL_STORAGE);
}
}
@Override
protected void onResume() {
super.onResume();
// Updates the activity every time the Activity becomes visible again
Assent.setActivity(this, this);
}
@Override
protected void onPause() {
super.onPause();
// Cleans up references of the Activity to avoid memory leaks
if (isFinishing())
Assent.setActivity(this, null);
}
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
// Lets Assent handle permission results, and contact your callbacks
Assent.handleResult(permissions, grantResults);
}
}
Without AssentFragment
If you don't want to extend AssentFragment, you can use some of Assent's other methods in order to mimic the behavior:
public class AssentFragment extends Fragment
implements FragmentCompat.OnRequestPermissionsResultCallback {
@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Assent.setFragment(this, this);
}
@Override
public void onResume() {
super.onResume();
Assent.setFragment(this, this);
}
@Override
public void onPause() {
super.onPause();
if (getActivity() != null && getActivity().isFinishing())
Assent.setFragment(this, null);
}
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
Assent.handleResult(permissions, grantResults);
}
}
Using PermissionResultSet
PermissionResultSet is returned in callbacks. It has a few useful methods:
PermissionResultSet result = // ... String[] permissions = result.getPermissions();
boolean granted = result.isGranted(permissions[0]);
Map<String, Boolean> grantedMap = result.getGrantedMap();
boolean allGranted = result.allPermissionsGranted();
Fragments
A huge plus to using callbacks rather than relying on onRequestPermissionsResult is that you can request permission from Fragments and receive the result right in the Fragment, as long as the Activity your Fragment is in handles results.
public class MainFragment extends Fragment {
// ... view creation logic and other stuff here
@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
if (!Assent.isPermissionGranted(Assent.WRITE_EXTERNAL_STORAGE)) {
Assent.requestPermissions(new AssentCallback() {
@Override
public void onPermissionResult(PermissionResultSet result) {
// Permission granted or denied
}
}
, 69, Assent.WRITE_EXTERNAL_STORAGE);
}
}
}
Duplicate and Simultaneous Requests
Duplicate Request Handling
If you were to do this...
Assent.requestPermissions(new AssentCallback() {
@Override
public void onPermissionResult(PermissionResultSet result) {
// Permission granted or denied
}
}
, 69, Assent.WRITE_EXTERNAL_STORAGE);
Assent.requestPermissions(new AssentCallback() {
@Override
public void onPermissionResult(PermissionResultSet result) {
// Permission granted or denied
}
}
, 69, Assent.WRITE_EXTERNAL_STORAGE);
...the permission would only be requested once, and both callbacks would be called at the same time.
An example situation where this would be useful: if you use tabs in your app, and multiple Fragments which are created at the same request the same permission, the permission dialog would only be shown once and both Fragments would be updated with the result.
Simultaneous Request Handling
If you were to do this...
Assent.requestPermissions(new AssentCallback() {
@Override
public void onPermissionResult(PermissionResultSet result) {
// Permission granted or denied
}
}
, 34, Assent.WRITE_EXTERNAL_STORAGE);
Assent.requestPermissions(new AssentCallback() {
@Override
public void onPermissionResult(PermissionResultSet result) {
// Permission granted or denied
}
}
, 69, Assent.ACCESS_FINE_LOCATION);
...Assent would wait until the first permission request is done before executing the second request.
This is important, because if you were you request different permissions at the same time without Assent, the first permission request would be cancelled and denied and the second one would be shown immediately.
AfterPermissionResult Annotation
As a convenience, you can use the AfterPermissionResult annotation to have Assent invoke a method in any class when a specific set of permissions is granted or denied.
public class MainActivity extends AssentActivity {
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Request WRITE_EXTERNAL_STORAGE and ACCESS_FINE_LOCATION permissions, with the current class as the target
Assent.requestPermissions(MainActivity.this, 69,
Assent.WRITE_EXTERNAL_STORAGE, Assent.ACCESS_FINE_LOCATION);
}
@AfterPermissionResult(permissions = {
Assent.WRITE_EXTERNAL_STORAGE, Assent.ACCESS_FINE_LOCATION
}
)
public void onPermissionResult(PermissionResultSet result) {
// Use PermissionResultSet
}
}
Behind the scenes, Assent is actually using a callback. When the callback is received, it finds the first AfterPermissionResult annotated method in the target class object (with a matching permission set) and invokes it.
The target class could be any object. It even works like this:
public class OtherClass {
@AfterPermissionResult(permissions = {
Assent.WRITE_EXTERNAL_STORAGE, Assent.ACCESS_FINE_LOCATION
}
)
public void onPermissionResult(PermissionResultSet result) {
// Use permission result
}
}
public class MainActivity extends AssentActivity {
private OtherClass mOther;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mOther = new OtherClass();
// Request WRITE_EXTERNAL_STORAGE and ACCESS_FINE_LOCATION permissions, with mOther as the target
Assent.requestPermissions(mOther, 69,
Assent.WRITE_EXTERNAL_STORAGE, Assent.ACCESS_FINE_LOCATION);
}
}
LICENSE
Copyright 2016 Aidan Follestad
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.