Requesting Permissions at Run Time
Beginning in Android 6.0 (API level 23), users grant permissions to apps while the app is running, not when they install the app.
If the permission you need to add isn't listed under the normal permissions, you'll need to deal with "Runtime Permissions". Runtime permissions are permissions that are requested as they are needed while the app is running. These permissions will show a dialog to the user, similar to the following one:
The first step when adding a "Runtime Permission" is to add it to the AndroidManifest:
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.codepath.androidpermissionsdemo" >
<uses-permission android:name="android.permission.READ_CONTACTS" />
...
</manifest>
Next, you'll need to initiate the permission request and handle the result. The following code shows how to do this in the context of an Activity, but this is also possible from within a Fragment.
// MainActivity.java
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// In an actual app, you'd want to request a permission when the user performs an action
// that requires that permission.
getPermissionToReadUserContacts();
}
// Identifier for the permission request
private static final int READ_CONTACTS_PERMISSIONS_REQUEST = 1;
// Called when the user is performing an action which requires the app to read the
// user's contacts
public void getPermissionToReadUserContacts() {
// 1) Use the support library version ContextCompat.checkSelfPermission(...) to avoid
// checking the build version since Context.checkSelfPermission(...) is only available
// in Marshmallow
// 2) Always check for permission (even if permission has already been granted)
// since the user can revoke permissions at any time through Settings
if (ContextCompat.checkSelfPermission(this, Manifest.permission.READ_CONTACTS)
!= PackageManager.PERMISSION_GRANTED) {
// The permission is NOT already granted.
// Check if the user has been asked about this permission already and denied
// it. If so, we want to give more explanation about why the permission is needed.
if (shouldShowRequestPermissionRationale(
Manifest.permission.READ_CONTACTS)) {
// Show our own UI to explain to the user why we need to read the contacts
// before actually requesting the permission and showing the default UI
}
// Fire off an async request to actually get the permission
// This will show the standard permission request dialog UI
requestPermissions(new String[]{Manifest.permission.READ_CONTACTS},
READ_CONTACTS_PERMISSIONS_REQUEST);
}
}
// Callback with the request from calling requestPermissions(...)
@Override
public void onRequestPermissionsResult(int requestCode,
@NonNull String permissions[],
@NonNull int[] grantResults) {
// Make sure it's our original READ_CONTACTS request
if (requestCode == READ_CONTACTS_PERMISSIONS_REQUEST) {
if (grantResults.length == 1 &&
grantResults[0] == PackageManager.PERMISSION_GRANTED) {
Toast.makeText(this, "Read Contacts permission granted", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(this, "Read Contacts permission denied", Toast.LENGTH_SHORT).show();
}
} else {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
}
}
}
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