How to handle permission denial in Kotlin Android

How to handle permission denial in Kotlin Android.

When developing Android applications, it is crucial to handle permission denial scenarios gracefully. Permission denial occurs when a user denies a requested permission, and it is essential to handle this situation appropriately to provide a good user experience.

In this tutorial, we will learn how to handle permission denial in Kotlin Android. We will explore the step-by-step process and provide code examples where applicable.

Step 1: Declare Permissions in Manifest File

To request permissions in an Android application, you need to declare them in the AndroidManifest.xml file. Open the manifest file and add the necessary permissions using the <uses-permission> tag. For example, to request the CAMERA permission, add the following line inside the <manifest> tag:

<uses-permission android:name="android.permission.CAMERA" />

Step 2: Check Permissions at Runtime

Before performing any operation that requires a specific permission, you need to check if the permission is granted or not. To check permissions at runtime, you can use the checkSelfPermission method. Here's an example of how to check if the CAMERA permission is granted:

if (ContextCompat.checkSelfPermission(
        this,
        Manifest.permission.CAMERA
    ) == PackageManager.PERMISSION_GRANTED
) {
    // Permission is granted, perform the operation
} else {
    // Permission is not granted, request the permission
}

Step 3: Request Permissions

If the required permission is not granted, you need to request it from the user. To request permissions at runtime, you can use the requestPermissions method. Here's an example of how to request the CAMERA permission:

val permission = Manifest.permission.CAMERA
val requestCode = 1

if (shouldShowRequestPermissionRationale(permission)) {
    // Show an explanation to the user
    // This can be done using a dialog or a custom view
} else {
    // Request the permission
    requestPermissions(arrayOf(permission), requestCode)
}

Step 4: Handle Permission Results

After the user responds to the permission request, the system calls the onRequestPermissionsResult method to handle the result. Inside this method, you can check if the permission was granted or denied. Here's an example of how to handle the permission result:

override fun onRequestPermissionsResult(
    requestCode: Int,
    permissions: Array<String>,
    grantResults: IntArray
) {
    when (requestCode) {
        1 -> {
            if (grantResults.isNotEmpty() && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                // Permission is granted, perform the operation
            } else {
                // Permission is denied, handle the denial
            }
            return
        }
    }
}

Step 5: Handle Permission Denial

When the user denies a permission, it is crucial to handle the denial gracefully. You can display a message or provide an alternative way for the user to perform the operation. Here's an example of how to handle permission denial:

// Inside the else block of onRequestPermissionsResult
Toast.makeText(this, "Permission denied. Cannot perform the operation.", Toast.LENGTH_SHORT).show()

You can customize the handling of permission denial based on your application's requirements. For example, you can prompt the user to grant the permission again or redirect them to a settings screen to manually enable the permission.

Conclusion

In this tutorial, we learned how to handle permission denial in Kotlin Android. We explored the step-by-step process, including declaring permissions in the manifest file, checking permissions at runtime, requesting permissions, and handling permission results. By following these steps, you can ensure that your application handles permission denial scenarios gracefully and provides a good user experience.