Creator

Creator

By debbuging after @RequiresBluetoothLocationPermission annotation program will exit function startScan in BluetoothLeScanner object

Could you please help me to find the problem why startScan function is not executed. By debugging after @RequiresBluetoothLocationPermission program will not go the next line.

My phone is Samsung Galaxy S22 Ultra Anfroid14, Compile Target SDK 34
Location, Connect, Scan - Permissions will be grandet at Run time This is a function that should be executed with provided ScanCallback

@RequiresLegacyBluetoothAdminPermission
@RequiresBluetoothScanPermission
**@RequiresBluetoothLocationPermission**
@RequiresPermission(android.Manifest.permission.BLUETOOTH_SCAN)
public void startScan(final ScanCallback callback) {
    startScan(null, new ScanSettings.Builder().build(), callback);
}

My program Code:

package com.example.navigationleftexample.ui.gallery;

import android.Manifest;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothManager;
import android.bluetooth.le.BluetoothLeScanner;
import android.bluetooth.le.ScanCallback;
import android.bluetooth.le.ScanResult;
import android.content.Context;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.CompoundButton;
import android.widget.ListView;
import android.widget.Switch;
import android.widget.TextView;
import android.widget.Toast;


import androidx.activity.result.ActivityResultLauncher;
import androidx.activity.result.contract.ActivityResultContracts;
import androidx.annotation.NonNull;
import androidx.core.app.ActivityCompat;
import androidx.core.content.ContextCompat;
import androidx.fragment.app.Fragment;
import androidx.fragment.app.ListFragment;
import androidx.lifecycle.ViewModelProvider;

import android.os.*;

import com.example.navigationleftexample.MainActivity;
import com.example.navigationleftexample.R;
import com.example.navigationleftexample.databinding.FragmentBluetoothBinding;
import com.example.navigationleftexample.ui.Bluetooth.LeDeviceListAdapter;

import pub.devrel.easypermissions.EasyPermissions;


public class BluetoothFragment extends Fragment {
Switch bluetoothSwitch;
private FragmentBluetoothBinding binding;
private BluetoothAdapter mBluetoothAdapter;

private LayoutInflater layoutInflater;
private BluetoothLeScanner bluetoothLeScanner;


private boolean scanning;
private Handler handler = new Handler();

public static final String[] BLUETOOTH_PERMISSIONS_S = 
{ Manifest.permission.BLUETOOTH_SCAN,     Manifest.permission.BLUETOOTH_CONNECT} ;


private static final int PERMISSION_REQUEST_COARSE_LOCATION = 456;

private static final int REQUEST_CODE_BLUETOOTH_SCAN = 1;

// Stops scanning after 10 seconds.
private static final long SCAN_PERIOD = 10000;



//LeDeviceListAdapter leDeviceListAdapter = new LeDeviceListAdapter(layoutInflater);
LeDeviceListAdapter leDeviceListAdapter;



private boolean checkPermission() {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
        int permission = ContextCompat.checkSelfPermission
 (getContext(),   Manifest.permission.ACCESS_FINE_LOCATION);
        return permission == PackageManager.PERMISSION_GRANTED;
    }else{
        return true;
    }
}
            // Device scan callback.
private ScanCallback leScanCallback =
        new ScanCallback() {
            @Override
            public void onScanResult(int callbackType, ScanResult result) {
                super.onScanResult(callbackType, result);
                leDeviceListAdapter.addDevice(result.getDevice());
                leDeviceListAdapter.notifyDataSetChanged();
            }
        };


private void scanLeDevice() {
    if (!scanning) {
        // Stops scanning after a predefined scan period.
        handler.postDelayed(new Runnable() {
            @Override
            public void run() {
                scanning = false;
                if (ActivityCompat.checkSelfPermission(getContext(),
         Manifest.permission.BLUETOOTH_SCAN) 
!= PackageManager.PERMISSION_GRANTED) {
                    // TODO: Consider calling
                    //    ActivityCompat#requestPermissions
                    // here to request the missing permissions, and then overriding
                    //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
                    //                                          int[] grantResults)
                    // to handle the case where the user grants the permission. See the documentation
                    // for ActivityCompat#requestPermissions for more details.
                    return;
                }
                bluetoothLeScanner.stopScan(leScanCallback);
            }
        }, SCAN_PERIOD);

        scanning = true;
        bluetoothLeScanner.startScan(leScanCallback);
    } else {
        scanning = false;
        //bluetoothLeScanner.stopScan(leScanCallback);
        scanLeDevice();
    }
}




public View onCreateView(@NonNull LayoutInflater inflater,
                         ViewGroup container, Bundle savedInstanceState) {
    BluetoothViewModel bluetoothViewModel =
            new ViewModelProvider(this).get(BluetoothViewModel.class);


    // Initializes a Bluetooth adapter.  For API level 18 and above, get a reference to
    // BluetoothAdapter through BluetoothManager.
    final BluetoothManager bluetoothManager =
            (BluetoothManager) getContext().getSystemService(Context.BLUETOOTH_SERVICE);
    mBluetoothAdapter = bluetoothManager.getAdapter();




    // Checks if Bluetooth is supported on the device.
    if (mBluetoothAdapter == null) {
        Toast.makeText(getContext(), R.string.ble_not_supported, Toast.LENGTH_SHORT).show();
        getActivity().finish();

    }
    bluetoothLeScanner = mBluetoothAdapter.getBluetoothLeScanner();

    layoutInflater = inflater;

    binding = FragmentBluetoothBinding.inflate(inflater, container, false);
    View root = binding.getRoot();


    // Check Bluetooth Switch
    bluetoothSwitch = (Switch) binding.switchBluetoothOn;
    bluetoothSwitch.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
            Toast.makeText(root.getContext(), "Bluetooth was changed", Toast.LENGTH_SHORT).show();
            if (isChecked==true)
            {

                // Use this check to determine whether BLE is supported on the device.  Then you can
                // selectively disable BLE-related features.
                if   (!getActivity().getPackageManager().
hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE)) {
                    Toast.makeText(getContext(), 
R.string.ble_not_supported,   Toast.LENGTH_SHORT).show();
                    getActivity().finish();
                }


                //  Check permissions for Bluetooth Connect
                if (ContextCompat.checkSelfPermission(getContext(), 
 Manifest.permission.BLUETOOTH_CONNECT) 
 == PackageManager.PERMISSION_DENIED)
                {
                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S)
                    {
                        ActivityCompat.requestPermissions(getActivity(), 
new String[] {Manifest.permission.BLUETOOTH_CONNECT}, 2);
                        return;
                    }
                }
                // Request Scan permission
                ActivityCompat.requestPermissions(getActivity(), 
new String[] 
{Manifest.permission.BLUETOOTH_SCAN}, REQUEST_CODE_BLUETOOTH_SCAN);



                boolean fineLocation = checkPermission();


                leDeviceListAdapter = new LeDeviceListAdapter(layoutInflater);
                scanLeDevice();
            }
            else
            {
                leDeviceListAdapter.clear();
                //scanLeDevice(false);
            }
        }
    });

    //  Show Connected Bluetooth Device
    final TextView textView = binding.textViewBluetoothDeviceChosen;
    bluetoothViewModel.getText().observe(getViewLifecycleOwner(), textView::setText);

    // Show List of Bluetooth scanned devices
    final ListView listView = (ListView) binding.listBluetoothDeviceView;
    //String [] deviceArray = bluetoothViewModel.getDeviceArray();





    listView.setAdapter(leDeviceListAdapter);

    // Create Listener for the List
    listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            final String item = (String) parent.getItemAtPosition(position);
            Toast.makeText(root.getContext(), "You have selected item: " + item,  
  Toast.LENGTH_SHORT).show();


        }
    });



    return root;
}

@Override
public void onAttach(@NonNull Context context) {
    super.onAttach(context);
    ActivityResultLauncher<String[]> locationPermissionRequest =
            registerForActivityResult(new ActivityResultContracts
                            .RequestMultiplePermissions(), result -> {
                        Boolean fineLocationGranted = result.getOrDefault(
                                Manifest.permission.ACCESS_FINE_LOCATION, false);
                        Boolean coarseLocationGranted = result.getOrDefault(
                                Manifest.permission.ACCESS_COARSE_LOCATION,false);
                        if (fineLocationGranted != null && fineLocationGranted) {
                            // Precise location access granted.
                            Toast.makeText(getContext(), "Precise location granted" ,  
 Toast.LENGTH_SHORT).show();
                        } else if (coarseLocationGranted != null && coarseLocationGranted) {
                            // Only approximate location access granted.
                            Toast.makeText(getContext(), "Aproximate location granted" , 
 Toast.LENGTH_SHORT).show();
                        } else {
                            // No location access granted.
                            Toast.makeText(getContext(), "No location granted" , 
 Toast.LENGTH_SHORT).show();
                        }
                    }
            );

    locationPermissionRequest.launch(new String[] {
            Manifest.permission.ACCESS_FINE_LOCATION,
            Manifest.permission.ACCESS_COARSE_LOCATION
    });
}

@Override
public void onDestroyView() {
    super.onDestroyView();
    binding = null;
}


}

Permissions from Android manifest:

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


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



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

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


<uses-feature android:name="android.hardware.bluetooth_le" />



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

<uses-permission android:name="android.permission.BLUETOOTH" android:maxSdkVersion="30" />


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

<uses-permission android:name="android.permission.VIBRATE" />
<uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
<uses-permission android:name="android.permission.USE_FULL_SCREEN_INTENT" />
<uses-permission android:name="android.permission.WAKE_LOCK" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.BILLING" />

Most Liked

Creator

Creator

Code is working fine. I have not initialized leDeviceListAdapter befor i set it to ListView

Where Next?

Popular Android topics Top

Joakins
Android studio displayed access is denied during gradle build C:\Program Files\Java\jdk1.8.0_251\native\68d5fa5c4cc2d200863cafc0d521ce42...
New
mpdizcashtag
Hi, this is my parrition informarion. A week ago I erased ‘system’ and now my hotpepper puya tablet bootloops. I have a gsi im trying to...
New
DAZ
Is it possible to develop an application that will generate NFC pulses even when the screen is off?
New
Shadow
Good afternoon. Brief story: My institution has several nfc tags in building which have to be scanned with specific app built and used in...
New
AndroidDog123
I’m a developer working as a contractor for a company. I’m finding it confusing on how I should answer these questions? Has Google just b...
New
faust
Honest question, do companies still use Java for their new android apps? I thought everybody was using Kotlin these days.
New
JesperBlom
Hi Hope it is a simple question :slight_smile: I am planning to use a new PC for making my enterprise app. Everything works perfect, b...
New
codergrid
I’m new to Android Studio, and curious about how long you’ve been using your Android Studio IDE. I read on Wikipedia that this year, Andr...
New
AnfaengerAlex
Hello, I’m a beginner in Android development and I’m facing an issue with my project setup. In my build.gradle.kts file, I have the foll...
New
Ujjwala
I’m developing an Android application in which I need to add functionality to automatically read a CSV file from a file manager, parse it...
New

Other popular topics Top

Devtalk
Reading something? Working on something? Planning something? Changing jobs even!? If you’re up for sharing, please let us know what you’...
1052 22283 402
New
AstonJ
Or looking forward to? :nerd_face:
498 14002 274
New
Exadra37
Please tell us what is your preferred monitor setup for programming(not gaming) and why you have chosen it. Does your monitor have eye p...
New
PragmaticBookshelf
Rust is an exciting new programming language combining the power of C with memory safety, fearless concurrency, and productivity boosters...
New
PragmaticBookshelf
Learn different ways of writing concurrent code in Elixir and increase your application's performance, without sacrificing scalability or...
New
PragmaticBookshelf
Build highly interactive applications without ever leaving Elixir, the way the experts do. Let LiveView take care of performance, scalabi...
New
New
AstonJ
If you’re getting errors like this: psql: error: connection to server on socket “/tmp/.s.PGSQL.5432” failed: No such file or directory ...
New
AstonJ
Curious what kind of results others are getting, I think actually prefer the 7B model to the 32B model, not only is it faster but the qua...
New
PragmaticBookshelf
A concise guide to MySQL 9 database administration, covering fundamental concepts, techniques, and best practices. Neil Smyth MySQL...
New