Android запрос разрешений kotlin

Requesting Android Runtime Permissions

Hello there, today we will discuss requesting Android runtime permissions and how to use them. Since the introduction of Android 6.0 Marshmallow (SDK 23), Android will prompt users to accept or deny the specific permissions to use some of the features within the application such as Camera, Location services, record audio, etc.

As the developers, of course, we must handle these new Android runtime permissions to use some specific features starting at SDK 23 above, otherwise, the app will crash. So how do we implement it?

What will you learn?

• Know how to check and request a runtime permissions on Android app.
• Understand how handle more than one Android runtime permissions.

Note: In this post, I used Android Studio Arctic Fox, make sure you use the latest Android Studio, or if you already install it, be sure to check the latest update. The Kotlin version that I used is Kotlin 1.6.10.

What will the app look like?

The app will look like this after you finish this tutorial:

Getting Started – Requesting Android Runtime Permissions

Open your Android Studio and choose to Start a new Android Studio Project. Then set the Application Name as you prefer, on this tutorial, I use RuntimePermissions and select Kotlin as the language. On the next screen, select Empty Activity and give the Activity Name MainActivity and wait until the Android Studio finishes preparing your project.

Preparing the XML Layout

The first is preparing the XML layout for our app here. Open the activity_main.xml inside the res/layout directory and put the code below:

The XML contains only two buttons, the first one, buttonRequestLocationPermissions is to check and request location service. While the last one buttonRequestCameraPermissions is to check and request camera and audio recording permissions.

Declaring Permissions on Manifest

The next step is to add permissions that we will use on the AndroidManifest.xml file:

After adding those permissions, proceed to the next step that is the coding step to check and request the Android runtime permissions.

Check and request location permission

For a single permission request, I will give the example of requesting the location permission, go to MainActivity.kt file and insert this code inside onCreate method:

findViewById(R.id.buttonRequestLocationPermissions).setOnClickListener

Then add insert a new function checkAndRequestLocationPermission :

private fun checkAndRequestLocationPermission() < if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) < // permission has not been granted, so request permission ActivityCompat.requestPermissions( this, arrayOf(Manifest.permission.ACCESS_FINE_LOCATION), REQUEST_LOCATION_CODE ) >else < // permission has been granted, continue as usual Toast.makeText(this, "Permission already been granted", Toast.LENGTH_SHORT).show() >>

This function or method is to check the permission first using ActivityCompat.checkSelfPermission() and if the user has not granted the permissions, we request the permission using ActivityCompat.requestPermissions() function.

Proceed to the next step to handle user callback on granting android runtime permissions. Insert callback function like this:

override fun onRequestPermissionsResult( requestCode: Int, permissions: Array, grantResults: IntArray ) < super.onRequestPermissionsResult(requestCode, permissions, grantResults) // handling callback on request location permission if (requestCode == REQUEST_LOCATION_CODE) < if (grantResults.size == 1 && grantResults.first() == PackageManager.PERMISSION_GRANTED) < // permission has been granted, continue as usual Toast.makeText(this, "Permission already been granted", Toast.LENGTH_SHORT).show() >else < // Permission was denied or request was cancelled Toast.makeText(this, "Permission denied or cancelled", Toast.LENGTH_SHORT).show() >> >

To handle the permission granting callbacks, we have to use onRequestPermissionsResult and check if specific permission has already been granted or denied.

When you run the app will be like this:

Check and request more than one permission

For checking and requesting more than one permission, I will give you another example of requesting camera and audio recording permissions. Same with location before, just add more parameters on ActivityCompat.

This is the final code of MainActivity.kt that already include request location and camera permissions:

import android.Manifest import android.content.pm.PackageManager import androidx.appcompat.app.AppCompatActivity import android.os.Bundle import android.widget.Toast import androidx.appcompat.widget.AppCompatButton import androidx.core.app.ActivityCompat class MainActivity : AppCompatActivity() < private val REQUEST_LOCATION_CODE = 100 private val REQUEST_CAMERA_CODE = 200 override fun onCreate(savedInstanceState: Bundle?) < super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) findViewById(R.id.buttonRequestLocationPermissions).setOnClickListener < checkAndRequestLocationPermission() >findViewById(R.id.buttonRequestCameraPermissions).setOnClickListener < checkAndRequestCameraPermissions() >> private fun checkAndRequestLocationPermission() < if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) < // permission has not been granted, so request permission ActivityCompat.requestPermissions( this, arrayOf(Manifest.permission.ACCESS_FINE_LOCATION), REQUEST_LOCATION_CODE ) >else < // permission has been granted, continue as usual Toast.makeText(this, "Permission already been granted", Toast.LENGTH_SHORT).show() >> private fun checkAndRequestCameraPermissions() < if ( ActivityCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.RECORD_AUDIO) != PackageManager.PERMISSION_GRANTED ) < // permission has not been granted, so request permission ActivityCompat.requestPermissions( this, arrayOf(Manifest.permission.CAMERA, Manifest.permission.RECORD_AUDIO), REQUEST_CAMERA_CODE ) >else < // permission has been granted, continue as usual Toast.makeText(this, "Permission already been granted", Toast.LENGTH_SHORT).show() >> override fun onRequestPermissionsResult( requestCode: Int, permissions: Array, grantResults: IntArray ) < super.onRequestPermissionsResult(requestCode, permissions, grantResults) // handling callback on request location permission if (requestCode == REQUEST_LOCATION_CODE) < if (grantResults.size == 1 && grantResults.first() == PackageManager.PERMISSION_GRANTED) < // permission has been granted, continue as usual Toast.makeText(this, "Permission already been granted", Toast.LENGTH_SHORT).show() >else < // Permission was denied or request was cancelled Toast.makeText(this, "Permission denied or cancelled", Toast.LENGTH_SHORT).show() >> // handling callback on request camera and record audio permission if (requestCode == REQUEST_CAMERA_CODE) < if ( grantResults.size == 2 && grantResults[0] == PackageManager.PERMISSION_GRANTED && grantResults[1] == PackageManager.PERMISSION_GRANTED ) < // permission has been granted, continue as usual Toast.makeText(this, "Permission already been granted", Toast.LENGTH_SHORT).show() >else < // Permission was denied or request was cancelled Toast.makeText(this, "Permission denied or cancelled", Toast.LENGTH_SHORT).show() >> > >

Where to go next?

You can download this full code from the link below:

Be sure to check my other cool posts here about:

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Request Permission Launcher with Kotlin in Android

In this article, we are learning about the run time permissions for request permission launchers. As we know that onRequestPermissionsResult is deprecated in the latest android API version. So we need to use r egisterForActivityResult() method instead onRequestPermissionsResult() as alternative of onRequestPermissionsResult() .

Let’s take an example where we need to access the camera to take pictures. First of all, you need to give use permission in your android manifest file.

Single Permission Request

let’s make a permission request.

private fun checkPermission() < val permission = ContextCompat.checkSelfPermission( requireContext(), Manifest.permission.CAMERA) if (permission != PackageManager.PERMISSION_GRANTED) < permissionsResultCallback.launch(Manifest.permission.CAMERA) >else < println("Permission isGranted") >>

Once you make a request for launch permission, the android os will show the popup for permission to allow and deny option and once the user click any option then we will get the callback with the result which needs to handle.

private val permissionsResultCallback = registerForActivityResult( ActivityResultContracts.RequestPermission()) < when (it) < true -> < println("Permission has been granted by user") >false -> < Toast.makeText(requireContext(), "Permission denied", Toast.LENGTH_SHORT).show() //show your custom dialog and naviage to Permission seetings >> >

Multiple Permission Request

Let’s take an example where we need to make multiple requests together to access the feature for example camera and microphone to record audio. First thing, these two permission should be added to android manifest file.

private fun checkPermissionRequired() < if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) < // direct navigate to respective screen >activity?.let < if (hasPermissions(activity as Context, PERMISSIONS)) < // direct navigate to respective screen >else < // request to launch permReqLauncher.launch( PERMISSIONS ) >> >

Check the permission is granted.

private fun hasPermissions(context: Context, permissions: Array): Boolean = permissions.all

Now if the permission is not given then request to launch permission.

private val permReqLauncher = registerForActivityResult(ActivityResultContracts.RequestMultiplePermissions()) < permissions ->val granted = permissions.entries.all < it.value == true >if (granted) < // navigate to respective screen >else < // show custom alert //Previously Permission Request was cancelled with 'Dont Ask Again', // Redirect to Settings after showing Information about why you need the permission showPermissionDialog() >>

If the permission is deny by user then better to show a dialog to convince user to access the feature of the app, you need to grant these permission. And navigate to Permission settings screen to allow the user to grant this permission.

private fun showPermissionDialog() < val builder = AlertDialog.Builder(requireContext()) builder.setTitle("Permission required") builder.setMessage("Some permissions are needed to be allowed to use this app without any problems.") builder.setPositiveButton("Grant") < dialog, which ->dialog.cancel() val intent = Intent(Settings.ACTION_APPLICATION_DETAILS_SETTINGS) intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK) val uri = Uri.fromParts("package", requireActivity().packageName, null) intent.data = uri startActivity(intent) > builder.setNegativeButton("Cancel") < dialog, which ->dialog.dismiss() > builder.show() >

That is all for this. Thanks for reading this article.

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