Every Android app runs in a limited-access sandbox. If an app needs to use resources or information outside of its own sandbox, the app has to request the appropriate permission. You declare that your app needs a permission by listing the permission in the app manifest and then requesting that the user approve each permission at runtime (on Android 6.0 and higher).
The basic principles are as follows:
- Ask for permissions in context, when the user starts to interact with the feature that requires it.
- Don't block the user. Always provide the option to cancel an educational UI flow related to permissions.
- If the user denies or revokes a permission that a feature needs, gracefully degrade your app so that the user can continue using your app, possibly by disabling the feature that requires the permission.
- Don't assume any system behavior.
This page walks through the step-by-step process of adding permissions to your app and requesting these permissions at runtime as needed.
Add permissions to the manifest
On all versions of Android, to declare that your app needs a permission,
put a
<uses-permission>
element in your app manifest, as a child of the top-level
<manifest> element.
For example, an app that needs to access the internet would have this line in the manifest:
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.snazzyapp">
<uses-permission android:name="android.permission.INTERNET"/>
<!-- other permissions go here -->
<application ...>
...
</application>
</manifest>
The system's behavior after you declare a permission depends on how sensitive the permission is. Some permissions are considered "normal" so the system immediately grants them upon installation. Other permissions are considered "dangerous" so the user must explicitly grant your app access. For more information about the different kinds of permissions, see Protection levels.
Check for permissions
If your app needs a dangerous permission, you must check whether you have that permission every time you perform an operation that requires that permission. On Android 6.0 (API level 23) and higher, users can revoke dangerous permissions from any app at any time.
Determine whether your app was already granted the permission
To check if the user has already granted your app a particular permission, pass
that permission into the
ContextCompat.checkSelfPermission()
method. This method returns either
PERMISSION_GRANTED
or PERMISSION_DENIED, depending on whether your app has the permission.
Explain why your app needs the permission
If the ContextCompat.checkSelfPermission() method returns PERMISSION_DENIED,
call shouldShowRequestPermissionRationale().
If this method returns true, show an educational UI to the user. In this UI,
describe why the feature, which the user wants to enable, needs a particular
permission.
Request permissions
After the user views an educational UI, or the return value of
shouldShowRequestPermissionRationale() indicates that you don't need to show
an educational UI this time, request the permission. Users see a system
permission dialog, where they can choose whether to grant a particular
permission to your app.
Traditionally, you manage a request code
yourself as part of the permission request and
include this request code in your permission callback logic. Another option is
to use the RequestPermission
contract, included in an AndroidX library, where you allow the system to manage
the permission request code for you. Because
using the RequestPermission contract simplifies your logic, it's recommended
that you use it when possible.
Allow the system to manage the permission request code
To allow the system to manage the request code that's associated with a
permissions request, add a dependency on the androidx.activity
library in your
module's build.gradle file. Use version 1.2.0 or later of the library.
You can then use one of the following classes:
- To request a single permission, use
RequestPermission. - To request multiple permissions at the same time, use
RequestMultiplePermissions.
The following steps show how to use the RequestPermission contract. The
process is nearly the same for the RequestMultiplePermissions contract.
In your activity or fragment's initialization logic, pass in an implementation of
ActivityResultCallbackinto a call toregisterForActivityResult(). TheActivityResultCallbackdefines how your app handles the user's response to the permission request.Keep a reference to the return value of
registerForActivityResult(), which is of typeActivityResultLauncher.To display the system permissions dialog when necessary, call the
launch()method on the instance ofActivityResultLauncherthat you saved in the previous step.After
launch()is called, the system permissions dialog appears. When the user makes a choice, the system asynchronously invokes your implementation ofActivityResultCallback, which you defined in the previous step.Note: Your app cannot customize the dialog that appears when you call
launch(). To provide more information or context to the user, change your app's UI so that it's easier for users to understand why a feature in your app needs a particular permission. For example, you might change the text in the button that enables the feature.Also, the text in the system permission dialog references the permission group associated with the permission that you requested. This permission grouping is designed for system ease-of-use, and your app shouldn't rely on permissions being within or outside of a specific permission group.
The following code snippet shows how to handle the permissions response:
Kotlin
// Register the permissions callback, which handles the user's response to the
// system permissions dialog. Save the return value, an instance of
// ActivityResultLauncher. You can use either a val, as shown in this snippet,
// or a lateinit var in your onAttach() or onCreate() method.
val requestPermissionLauncher =
registerForActivityResult(RequestPermission()
) { isGranted: Boolean ->
if (isGranted) {
// Permission is granted. Continue the action or workflow in your
// app.
} else {
// Explain to the user that the feature is unavailable because the
// features requires a permission that the user has denied. At the
// same time, respect the user's decision. Don't link to system
// settings in an effort to convince the user to change their
// decision.
}
}
Java
// Register the permissions callback, which handles the user's response to the
// system permissions dialog. Save the return value, an instance of
// ActivityResultLauncher, as an instance variable.
private ActivityResultLauncher<String> requestPermissionLauncher =
registerForActivityResult(new RequestPermission(), isGranted -> {
if (isGranted) {
// Permission is granted. Continue the action or workflow in your
// app.
} else {
// Explain to the user that the feature is unavailable because the
// features requires a permission that the user has denied. At the
// same time, respect the user's decision. Don't link to system
// settings in an effort to convince the user to change their
// decision.
}
});
And this code snippet demonstrates the recommended process of checking for a permission, and requesting a permission from the user when necessary:
Kotlin
when {
ContextCompat.checkSelfPermission(
CONTEXT,
Manifest.permission.REQUESTED_PERMISSION
) == PackageManager.PERMISSION_GRANTED -> {
// You can use the API that requires the permission.
}
shouldShowRequestPermissionRationale(...) -> {
// In an educational UI, explain to the user why your app requires this
// permission for a specific feature to behave as expected. In this UI,
// include a "cancel" or "no thanks" button that allows the user to
// continue using your app without granting the permission.
showInContextUI(...)
}
else -> {
// You can directly ask for the permission.
// The registered ActivityResultCallback gets the result of this request.
requestPermissionLauncher.launch(
Manifest.permission.REQUESTED_PERMISSION)
}
}
Java
if (ContextCompat.checkSelfPermission(
CONTEXT, Manifest.permission.REQUESTED_PERMISSION) ==
PackageManager.PERMISSION_GRANTED) {
// You can use the API that requires the permission.
performAction(...);
} else if (shouldShowRequestPermissionRationale(...)) {
// In an educational UI, explain to the user why your app requires this
// permission for a specific feature to behave as expected. In this UI,
// include a "cancel" or "no thanks" button that allows the user to
// continue using your app without granting the permission.
showInContextUI(...);
} else {
// You can directly ask for the permission.
// The registered ActivityResultCallback gets the result of this request.
requestPermissionLauncher.launch(
Manifest.permission.REQUESTED_PERMISSION);
}
Manage the permission request code yourself
As an alternative to allowing the system to manage the permission request
code, you can manage the permission request
code yourself. To do so, include the request code in a call to
requestPermissions().
The following code snippet demonstrates how to request a permission using a request code:
Kotlin
when {
ContextCompat.checkSelfPermission(
CONTEXT,
Manifest.permission.REQUESTED_PERMISSION
) == PackageManager.PERMISSION_GRANTED -> {
// You can use the API that requires the permission.
performAction(...)
}
shouldShowRequestPermissionRationale(...) -> {
// In an educational UI, explain to the user why your app requires this
// permission for a specific feature to behave as expected. In this UI,
// include a "cancel" or "no thanks" button that allows the user to
// continue using your app without granting the permission.
showInContextUI(...)
}
else -> {
// You can directly ask for the permission.
requestPermissions(CONTEXT,
arrayOf(Manifest.permission.REQUESTED_PERMISSION),
REQUEST_CODE)
}
}
Java
if (ContextCompat.checkSelfPermission(
CONTEXT, Manifest.permission.REQUESTED_PERMISSION) ==
PackageManager.PERMISSION_GRANTED) {
// You can use the API that requires the permission.
performAction(...);
} else if (shouldShowRequestPermissionRationale(...)) {
// In an educational UI, explain to the user why your app requires this
// permission for a specific feature to behave as expected. In this UI,
// include a "cancel" or "no thanks" button that allows the user to
// continue using your app without granting the permission.
showInContextUI(...);
} else {
// You can directly ask for the permission.
requestPermissions(CONTEXT,
new String[] { Manifest.permission.REQUESTED_PERMISSION },
REQUEST_CODE);
}
After the user responds to the system permissions dialog, the system then
invokes your app's implementation of onRequestPermissionsResult(). The system passes in the user
response to the permission dialog, as well as the request code that you defined,
as shown in the following code snippet:
Kotlin
override fun onRequestPermissionsResult(requestCode: Int,
permissions: Array<String>, grantResults: IntArray) {
when (requestCode) {
PERMISSION_REQUEST_CODE -> {
// If request is cancelled, the result arrays are empty.
if ((grantResults.isNotEmpty() &&
grantResults[0] == PackageManager.PERMISSION_GRANTED)) {
// Permission is granted. Continue the action or workflow
// in your app.
} else {
// Explain to the user that the feature is unavailable because
// the features requires a permission that the user has denied.
// At the same time, respect the user's decision. Don't link to
// system settings in an effort to convince the user to change
// their decision.
}
return
}
// Add other 'when' lines to check for other
// permissions this app might request.
else -> {
// Ignore all other requests.
}
}
}
Java
@Override
public void onRequestPermissionsResults(int requestCode, String[] permissions,
int[] grantResults) {
switch (requestCode) {
case PERMISSION_REQUEST_CODE:
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0 &&
grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// Permission is granted. Continue the action or workflow
// in your app.
} else {
// Explain to the user that the feature is unavailable because
// the features requires a permission that the user has denied.
// At the same time, respect the user's decision. Don't link to
// system settings in an effort to convince the user to change
// their decision.
}
return;
}
// Other 'case' lines to check for other
// permissions this app might request.
}
}
Handle permission denial
If the user denies a permission request, your app should help users understand the implications of denying the permission. In particular, your app should make users aware of the features that don't work because of the missing permission. When you do so, keep the following best practices in mind:
Guide the user's attention. Highlight a specific part of your app's UI where there's limited functionality because your app doesn't have the necessary permission. Several examples of what you could do include the following:
- Show a message where the feature's results or data would have appeared.
- Display a different button that contains an error icon and color.
Be specific. Don't display a generic message; instead, mention which features are unavailable because your app doesn't have the necessary permission.
Don't block the user interface. In other words, don't display a full-screen warning message that prevents users from continuing to use your app at all.
In certain situations, the permission might be denied automatically, without the user taking any action. (Similarly, a permission might be granted automatically as well.) It's important to not assume anything about automatic behavior. Each time your app needs to access functionality that requires a permission, you should check that your app is still granted that permission.
To provide the best user experience when asking for app permissions, also see App Permissions Best Practices.
Request to become the default handler if necessary
Some apps depend on access to sensitive user information related to call logs and SMS messages. If you want to request the permissions specific to call logs and SMS messages and publish your app to the Play Store, you must prompt the user to set your app as the default handler for a core system function before requesting these runtime permissions.
For more information on default handlers, including guidance on showing a default handler prompt to users, see the guide on permissions used only in default handlers.
Declare permissions by API level
To declare a permission only on devices that support runtime permissions—that
is, devices running Android 6.0 (API level 23) or higher—include the
uses-permission-sdk-23
tag instead of the
uses-permission tag.
When using either of these tags, you can set the maxSdkVersion attribute to
specify that, on devices running a higher version, a particular permission isn't
needed.
Additional resources
For additional information about permissions, read these articles:
To learn more about requesting permissions, download the following sample apps: