Android check permission from fragment

Request app permissions

Every Android app runs in a limited-access sandbox. If your app needs to use resources or information outside of its own sandbox, you can declare a permission and set up a permission request that provides this access. These steps are part of the workflow for using permissions.

If you declare any dangerous permissions, and if your app is installed on a device that runs Android 6.0 (API level 23) or higher, you must request the dangerous permissions at runtime by following the steps in this guide.

If you don’t declare any dangerous permissions, or if your app is installed on a device that runs Android 5.1 (API level 22) or lower, the permissions are automatically granted, and you don’t need to complete any of the remaining steps on this page.

Basic principles

The basic principles for requesting permissions at runtime 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. For example, don’t assume that permissions appear in the same permission group. A permission group merely helps the system minimize the number of system dialogs that are presented to the user when an app requests closely-related permissions.

Workflow for requesting permissions

Before you declare and request runtime permissions in your app, evaluate whether your app needs to do so. You can fulfill many use cases in your app, such as taking photos, pausing media playback, and displaying relevant ads, without needing to declare any permissions.

If you conclude that your app needs to declare and request runtime permissions, complete these steps:

1. In your app’s manifest file, declare the permissions that your app might need to request.
2. Design your app’s UX so that specific actions in your app are associated with specific runtime permissions. Users should know which actions might require them to grant permission for your app to access private user data.
3. Wait for the user to invoke the task or action in your app that requires access to specific private user data. At that time, your app can request the runtime permission that’s required for accessing that data.

Check whether the user has already granted the runtime permission that your app requires. If so, your app can access the private user data. If not, continue to the next step.

You must check whether you have that permission every time you perform an operation that requires that permission.

Check whether your app should show a rationale to the user, explaining why your app needs the user to grant a particular runtime permission. If the system determines that your app shouldn’t show a rationale, continue to the next step directly, without showing a UI element.

If the system determines that your app should show a rationale, however, present the rationale to the user in a UI element. This rationale should clearly explain what data your app is trying to access, and what benefits the app can provide to the user if they grant the runtime permission. After the user acknowledges the rationale, continue to the next step.

Request the runtime permission that your app requires in order to access the private user data. The system displays a runtime permission prompt, such as the one shown on the permissions overview page.

Check the user’s response, whether they chose to grant or deny the runtime permission.

If the user granted the permission to your app, you can access the private user data. If the user denied the permission instead, gracefully degrade your app experience so that it provides functionality to the user, even without the information that’s protected by that permission.

Figure 1 illustrates the workflow and set of decisions associated with this process:

Figure 1. Diagram that shows the workflow for declaring and requesting runtime permissions on Android.

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.

Additionally, if your app requests a permission related to location, microphone, or camera, consider explaining why your app needs access to this information.

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 dependencies on the following libraries in your module’s build.gradle file:

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 ActivityResultCallback into a call to registerForActivityResult() . The ActivityResultCallback defines how your app handles the user’s response to the permission request.

Keep a reference to the return value of registerForActivityResult() , which is of type ActivityResultLauncher .

To display the system permissions dialog when necessary, call the launch() method on the instance of ActivityResultLauncher that 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 of ActivityResultCallback , 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

And this code snippet demonstrates the recommended process of checking for a permission, and requesting a permission from the user when necessary:

Kotlin

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() .

Note: Your app cannot customize the dialog that appears when you call requestPermissions() . The text in the system permission dialog references a permission group, but this permission grouping is designed for system ease-of-use. Your app shouldn’t rely on permissions being within or outside of a specific permission group.

The following code snippet demonstrates how to request a permission using a request code:

Kotlin

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

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.

At the same time, your app should respect the user’s decision to deny a permission. Starting in Android 11 (API level 30), if the user taps Deny for a specific permission more than once during your app’s lifetime of installation on a device, the user doesn’t see the system permissions dialog if your app requests that permission again. The user’s action implies «don’t ask again.» On previous versions, users would see the system permissions dialog each time your app requested a permission, unless the user had previously selected a «don’t ask again» checkbox or option.

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.

One-time permissions

Starting in Android 11 (API level 30), whenever your app requests a permission related to location, microphone, or camera, the user-facing permissions dialog contains an option called Only this time, as shown in Figure 2. If the user selects this option in the dialog, your app is granted a temporary one-time permission.

Your app can then access the related data for a period of time that depends on your app’s behavior and the user’s actions:

• While your app’s activity is visible, your app can access the data.
• If the user sends your app to the background, your app can continue to access the data for a short period of time.
• If you launch a foreground service while the activity is visible, and the user then moves your app to the background, your app can continue to access the data until that foreground service stops.
• If the user revokes the one-time permission, such as in system settings, your app cannot access the data, regardless of whether you launched a foreground service. As with any permission, if the user revokes your app’s one-time permission, your app’s process terminates.

When the user next opens your app and a feature in your app requests access to location, microphone, or camera, the user is prompted for the permission again.

Android auto-resets permissions of unused apps

If your app targets Android 11 (API level 30) or higher and isn’t used for a few months, the system protects user data by automatically resetting the sensitive runtime permissions that the user had granted your app. Learn more in the guide about app hibernation.

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.

Grant all runtime permissions for testing purposes

To grant all runtime permissions automatically when you install an app on an emulator or test device, use the -g option for the adb shell install command, as demonstrated in the following code snippet:

Additional resources

For additional information about permissions, read these articles:

To learn more about requesting permissions, download the following sample apps:

• Android RuntimePermissionsBasic Sample Java | Kotlin

Content and code samples on this page are subject to the licenses described in the Content License. Java is a registered trademark of Oracle and/or its affiliates.

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Handle Runtime Permissions in Android

• From beginning with Android 6.0 Marshmallow (API LEVEL 23)(
  Marshmallow was released on October 5, 2015 ), Google has introduced a new runtime permission model.
• According to this model users are not prompted for permission at the time of installing the app, rather developers need to check for and request permission at runtime (i.e. The particular permission must required before performing any action)
• Users can then allow or deny the permission, users can also grant or revoke permission anytime from settings even if the app is already installed.
• Developers have to handle all the use cases. If not handled properly, it can cause application crashes.

Now here we’ll look into the android runtime permissions and handle them.

Types of Runtime Permissions

Android defines basically three types of permissions:

1. Normal Permissions
2. Signature Permissions
3. Dangerous Permissions

Both Normal and Dangerous permissions must be defined in the Manifest file. But only Dangerous permissions are checked at runtime, Normal permissions are not.

Normal Permissions

Some permissions are automatically granted to the application. Just we need to declare those permissions in AndroidManifest.xml and it will work fine. Those permissions are called Normal Permissions. An example of a normal permission is INTERNET .

Normal Permissions are automatically granted to the application.

Signature Permissions

A permission that the system grants only if the requesting application is signed with the same certificate as the application that declared the permission. If the certificates match, the system automatically grants the permission without notifying the user or asking for the user’s explicit approval.

Dangerous Permissions

Some permissions may affect the users private information, or could potentially affect his data or the operation of other application are called Dangerous Permissions. For example, the ability to read the user’s contacts is a dangerous permission. Some other examples are CONTACTS , CAMERA , CALENDAR, LOCATION , PHONE , STORAGE , SENSORS , MICROPHONE, etc.

Dangerous permissions must be granted by the user at runtime to the app.

Dangerous permissions are grouped into categories that make it easier for the user to understand what they are allowing the application to do. If any permission in a Permission Group is granted. Another permission in the same group will be automatically granted as well. For example , once WRITE_CONTACTS is granted, application will also grant READ_CONTACTS and GET_ACCOUNTS as all three permissions in the same group.

Before Marshmallow (API 23)

Before Marshmallow (API 23) all the requested permissions are presented to the user before installing the application. If the user denies a required permission, the related application cannot be installed. And there was no way to grant or deny any permission after installation.

Workflow of Runtime Permission

Here is the workflow of runtime permission to open camera in android.

First of all we check the SDK Version. If SDK version is less than 23(Marshmallow) then we don’t need to ask for permission as Runtime Permission started from Marshmallow. And we can open camera.

If SDK version is equal to or greater than 23, then we check the permission is already granted or not by calling contextCompat.checkSelfPermission(). If permission is granted then we can open camera. If the permission is not granted we must request for the permission to the user. But in this case, we have to handle three cases.

Case 1:

The permission never asked before.

Case 2:

The permission asked before but user denied without checking ‘Never ask again’.

Case 3:

The permission asked before but user denied with checking ‘Never ask again’.

Only a method can handle our three cases . The method is shouldShowRequestPermissionRationale. the method returns a boolean value.

This method returns true if the the permission asked before but the user denied without checking ‘Never ask again’. which matches our Case 2.

But it will return false in two cases.

• If the permission is requested first time. Which matches our Case 1.
• If the permission asked before but the user denied with checking ‘Never ask again’. Which matches our Case 3.

So here only shouldShowRequestPermissionRationale method can match our three cases. Now just need to solve them with help of this method.

Solution of Case 2:

Solution of case 2 is very easy. Because the method shouldShowRequestPermissionRationale returns true only when the permission asked before but the user denied without checking ‘Never ask again’. So we can just give an explanation about why the app needs this permission. And if the user agree to our explanation we can request for permission again. That’s it.

Solution of Case 1 and Case 3:

But solution of case 1 and case 2 is little tricky. Because we know the method shouldShowRequestPermissionRationale returns false if the permission never asked before (Case 1) or the permission asked but the user denied with checking ‘Never ask again’ (Case 3). But we have to catch this two cases. How can we do that ?

Yes we can do this with the help of Shared Preferences , We can just put a flag on Shared Preferences for checking weather the permission is being asked first time or not. And the problem is solved. By this following code we can put our flag on Shared Preferences.

In firstTimeAsking, we just put a boolean flag with the permission string as key.

In isFirstTimeAsking, we get the value associated with the permission string and return it.

Notice that we set the default value as true. That’s why if the key is not in the preference file or even if the file itself is not created, the android framework will automatically create a file with the name we gave and will return the default value we set.

We will call this method every time when a permission request is required but after first call, we set the flag as false using firstTimeAsking(permission, false).

Here is the code.

We can put all these logic in a method and use a callback to get which case we should handle now. The code would be like this.

Now all the three cases are solved.

If you still getting confused on how to use it and you want to be more clear then see this full project Runtime Permission in Android in Github.

Handle the permissions request response

When the user responds to your app’s permission request, the system invokes your app’s onRequestPermissionsResult() method. So you have to override that method to find out whether the permission was granted or denied. And the same request code that you passed to requestPermissions() method is also passed to the callback. For deeper understanding, you see the following callback method:

Asking for Multiple Permissions at a time

Permissions from Fragment

In Fragment, you can ask for permission in two ways

Way 1:

In this way you will get permission result on onRequestPermissionsResult method of the activity not the fragment. That’s why you have to override the onRequestPermissionsResult method of the activity instead of Fragment.

Way 2:

In this way you will get permission result on onRequestPermissionsResult() method of fragment. But you must call

in activity’s onRequestPermissionsResult() method.

So the best way is

1) In fragment, ask permission just using

2) In activity’s onRequestPermissionsResult, call

so it will pass the result to fragment. Mind it this is the most important call and you must do it.

3) Now in fragment’s onRequestPermissionsResult, write the code that you want to handle the result.

ContextCompat vs AcitvityCompat

ActivityCompat is a subclass (child) of ContextCompat so you can pass either one whenever object of ContextCompat class is required.

This method is used simply for checking whether you are having requested permission available for your app or not.

This method is used for requesting permissions.

Shorten source code with 3rd Party Library

There are many popular permissions libraries that you can use for shorten your code. Some of them are given below:

I hope this article will helpful for you. Feel free to give your feedback in comment below: I would be very happy to get new suggestions.

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