0%

Easy Permissions

EasyPermissions is a wrapper library to simplify basic system permissions logic when targeting Android M or higher.

Easy Permissions

Installation

EasyPermissions is installed by adding the following dependency to your build.gradle file:

1
2
3
dependencies {
compile 'pub.devrel:easypermissions:0.3.0'
}

Usage

Basic

To begin using EasyPermissions, have your Activity (or Fragment) override the onRequestPermissionsResult method:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}

@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);

// Forward results to EasyPermissions
EasyPermissions.onRequestPermissionsResult(requestCode, permissions, grantResults, this);
}
}

Request Permissions

The example below shows how to request permissions for a method that requires both
CAMERA and CHANGE_WIFI_STATE permissions. There are a few things to note:

  • Using EasyPermissions#hasPermissions(...) to check if the app already has the
    required permissions. This method can take any number of permissions as its final
    argument.
  • Requesting permissions with EasyPermissions#requestPermissions. This method
    will request the system permissions and show the rationale string provided if
    necessary. The request code provided should be unique to this request, and the method
    can take any number of permissions as its final argument.
  • Use of the AfterPermissionGranted annotation. This is optional, but provided for
    convenience. If all of the permissions in a given request are granted, any methods
    annotated with the proper request code will be executed. This is to simplify the common
    flow of needing to run the requesting method after all of its permissions have been granted.
    This can also be achieved by adding logic on the onPermissionsGranted callback.
1
2
3
4
5
6
7
8
9
10
11
12
@AfterPermissionGranted(RC_CAMERA_AND_WIFI)
private void methodRequiresTwoPermission() {
String[] perms = {Manifest.permission.CAMERA, Manifest.permission.CHANGE_WIFI_STATE};
if (EasyPermissions.hasPermissions(this, perms)) {
// Already have permission, do the thing
// ...
} else {
// Do not have permissions, request them now
EasyPermissions.requestPermissions(this, getString(R.string.camera_and_wifi_rationale),
RC_CAMERA_AND_WIFI, perms);
}
}

Optionally, for a finer control, you can have your Activity / Fragment implement
the PermissionCallbacks interface.

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
public class MainActivity extends AppCompatActivity implements EasyPermissions.PermissionCallbacks {

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

@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);

// Forward results to EasyPermissions
EasyPermissions.onRequestPermissionsResult(requestCode, permissions, grantResults, this);
}

@Override
public void onPermissionsGranted(int requestCode, List<String> list) {
// Some permissions have been granted
// ...
}

@Override
public void onPermissionsDenied(int requestCode, List<String> list) {
// Some permissions have been denied
// ...
}
}

Required Permissions

In some cases your app will not function properly without certain permissions. If the user
denies these permissions with the “Never Ask Again” option, you will be unable to request
these permissions from the user and they must be changed in app settings. You can use the
method EasyPermissions.somePermissionPermanentlyDenied(...) to display a dialog to the
user in this situation and direct them to the system setting screen for your app:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
@Override
public void onPermissionsDenied(int requestCode, List<String> perms) {
Log.d(TAG, "onPermissionsDenied:" + requestCode + ":" + perms.size());

// (Optional) Check whether the user denied any permissions and checked "NEVER ASK AGAIN."
// This will display a dialog directing them to enable the permission in app settings.
if (EasyPermissions.somePermissionPermanentlyDenied(this, perms)) {
new AppSettingsDialog.Builder(this).build().show();
}
}

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);

if (requestCode == AppSettingsDialog.DEFAULT_SETTINGS_REQ_CODE) {
// Do something after user returned from app settings screen, like showing a Toast.
Toast.makeText(this, R.string.returned_from_app_settings_to_activity, Toast.LENGTH_SHORT)
.show();
}
}

欢迎关注我的其它发布渠道