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

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