startActivityForResult is deprecated and, unable to request for bluetooth connection with new code

Question

Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);

I was requesting to start Bluetooth using above source code. But, startActivityForResult is deprecated. So, I was searching for new code how to deal with that. Here's the solution I found.

// You can do the assignment inside onAttach or onCreate, i.e, before the activity is displayed
    ActivityResultLauncher<Intent> someActivityResultLauncher = registerForActivityResult(
            new ActivityResultContracts.StartActivityForResult(),
            new ActivityResultCallback<ActivityResult>() {
                @Override
                public void onActivityResult(ActivityResult result) {
                    if (result.getResultCode() == Activity.RESULT_OK) {
                        // There are no request codes
                        Intent data = result.getData();
                        doSomeOperations();
                    }
                }
            });

    public void openSomeActivityForResult() {
        Intent intent = new Intent(this, SomeActivity.class);
        someActivityResultLauncher.launch(intent);
    }

I added it to my source code.

            Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
//            startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);

            ActivityResultLauncher<Intent> someActivityResultLauncher = registerForActivityResult(
                    new ActivityResultContracts.StartActivityForResult(),
                    new ActivityResultCallback<ActivityResult>() {
                        @Override
                        public void onActivityResult(ActivityResult result) {
                            if (result.getResultCode() == Activity.RESULT_OK) {
                                // There are no request codes
                                Intent data = result.getData();
//                                doSomeOperations();
                            }
                        }
                    });

            someActivityResultLauncher.launch(enableBtIntent);

But, Android is requesting for bluetooth permission automatically for old source code (I didn't have to add onActivityResult function. Cause, it was earlier written in background). But, when I am using ActivityResultLauncher I must add onActivityResult function(I can work without onActivityResult also But, startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT); I had sent an integer value also REQUEST_ENABLE_BT=1). How can I request for bluetooth permission with new code?

Answer 1

100% working solution

manifest code:

   <!--BLUETOOTH PERMISSION-->
    <!-- Request legacy Bluetooth permissions on older devices. -->
    <uses-permission android:name="android.permission.BLUETOOTH" />
    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
    <!-- Needed only if your app looks for Bluetooth devices.
             If your app doesn't use Bluetooth scan results to derive physical
             location information, you can strongly assert that your app
             doesn't derive physical location. -->
    <uses-permission android:name="android.permission.BLUETOOTH_SCAN" />
    <!-- Needed only if your app makes the device discoverable to Bluetooth
      devices. -->
    <uses-permission android:name="android.permission.BLUETOOTH_ADVERTISE" />
    <!-- Needed only if your app communicates with already-paired Bluetooth
           devices. -->
    <uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
    <!--bibo01 : hardware option-->
    <uses-feature android:name="android.hardware.bluetooth" android:required="false"/>
    <uses-feature android:name="android.hardware.bluetooth_le" android:required="false"/>

Kotlin code:

 //check android12+
                        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
                            requestMultiplePermissions.launch(arrayOf(
                                Manifest.permission.BLUETOOTH_SCAN,
                                Manifest.permission.BLUETOOTH_CONNECT))
                        }
                        else{
                            val enableBtIntent = Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE)
                            requestBluetooth.launch(enableBtIntent)
                        }
....................................................

private var requestBluetooth = registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
                if (result.resultCode == RESULT_OK) {
                    //granted
                }else{
                    //deny
                }
 }

private val requestMultiplePermissions =
                registerForActivityResult(ActivityResultContracts.RequestMultiplePermissions()) { permissions ->
                    permissions.entries.forEach {
                        Log.d("test006", "${it.key} = ${it.value}")
                    }
}

Read more: https://developer.android.com/guide/topics/connectivity/bluetooth/permissions