我正在android studio中使用蓝牙扫描仪。我还在学习，所以对于所有这些愚蠢的错误，我感到非常抱歉。我有一段时间以前工作，但无法从设备获取UUID。所以我搜索和搜索，最后我有一些工作。但现在问题是扫描后只有一个BLE设备。该列表不会扩展。如果我使用其他扫描应用程序，我会找到多个设备。
我们非常感谢您的帮助，欢迎任何有关我的新代码的反馈！
声明：请知道我使用了一些我在网上找到的代码，所以如果有什么无用或者很奇怪，请通知我..
public class Scanner_BTLE {
private MainActivity ma;
private BluetoothAdapter mBluetoothAdapter;
private boolean mScanning;
private Handler mHandler;
private long scanPeriod;
private int signalStrength;
public Scanner_BTLE(MainActivity mainActivity, long scanPeriod, int signalStrength) {
ma = mainActivity;
mHandler = new Handler();
this.scanPeriod = scanPeriod;
this.signalStrength = signalStrength;
final BluetoothManager bluetoothManager =
(BluetoothManager) ma.getSystemService(Context.BLUETOOTH_SERVICE);
mBluetoothAdapter = bluetoothManager.getAdapter();
}
// Device scan callback.
private BluetoothAdapter.LeScanCallback mLeScanCallback =
new BluetoothAdapter.LeScanCallback() {
@Override
public void onLeScan(final BluetoothDevice device, int rssi, final byte[] scanRecord) {
final int new_rssi = rssi;
int startByte = 2;
boolean patternFound = false;
while (startByte <= 5) {
if (((int) scanRecord[startByte + 2] & 0xff) == 0x02 && //Identifies an iBeacon
((int) scanRecord[startByte + 3] & 0xff) == 0x15) { //Identifies correct data length
patternFound = true;
break;
}
startByte++;
}
if (patternFound) {
//Convert to hex String
byte[] uuidBytes = new byte[16];
System.arraycopy(scanRecord, startByte + 4, uuidBytes, 0, 16);
String hexString = bytesToHex(uuidBytes);
//UUID detection
final String uuid = hexString.substring(0, 8) + "-" +
hexString.substring(8, 12) + "-" +
hexString.substring(12, 16) + "-" +
hexString.substring(16, 20) + "-" +
hexString.substring(20, 32);
// major
final int major = (scanRecord[startByte + 20] & 0xff) * 0x100 + (scanRecord[startByte + 21] & 0xff);
// minor
final int minor = (scanRecord[startByte + 22] & 0xff) * 0x100 + (scanRecord[startByte + 23] & 0xff);
if (rssi > signalStrength) {
mHandler.post(new Runnable() {
@Override
public void run() {
ma.addDevice(device, new_rssi, scanRecord, major, minor, uuid);
}
});
}
}
}
}
;
public boolean isScanning() {
return mScanning;
}
public void start() {
if (!Utils.checkBluetooth(mBluetoothAdapter)) {
Utils.requestUserBluetooth(ma);
ma.stopScan();
} else {
scanLeDevice(true);
}
}
public void stop() {
scanLeDevice(false);
}
// If you want to scan for only specific types of peripherals,
// you can instead call startLeScan(UUID[], BluetoothAdapter.LeScanCallback),
// providing an array of UUID objects that specify the GATT services your app supports.
private void scanLeDevice(final boolean enable) {
if (enable && !mScanning) {
Utils.toast(ma.getApplicationContext(), "Starting BLE scan...");
// Stops scanning after a pre-defined scan period.
mHandler.postDelayed(new Runnable() {
@Override
public void run() {
Utils.toast(ma.getApplicationContext(), "Stopping BLE scan...");
mScanning = false;
mBluetoothAdapter.stopLeScan(mLeScanCallback);
ma.stopScan();
}
}, scanPeriod);
mScanning = true;
mBluetoothAdapter.startLeScan(mLeScanCallback);
} else {
mScanning = false;
mBluetoothAdapter.stopLeScan(mLeScanCallback);
}
}
}
BTLE_DEVICE
public class BTLE_Device {
private BluetoothDevice bluetoothDevice;
private int rssi;
private String uuid;
private int major;
private int minor;
public BTLE_Device(BluetoothDevice bluetoothDevice) {
this.bluetoothDevice = bluetoothDevice;
}
public void setRSSI(int rssi) {
this.rssi = rssi;
}
public int getRSSI() {
return rssi;
}
public String getUuid() {
return uuid;
}
public void setUuid(String uuid) {
this.uuid = uuid;
}
public int getMajor() {
return major;
}
public void setMajor(int major) {
this.major = major;
}
public int getMinor() {
return minor;
}
public void setMinor(int minor) {
this.minor = minor;
}
}
列表适配器（不知道我是否这样做:)）
public class ListAdapter_BTLE_Devices extends ArrayAdapter<BTLE_Device> {
Activity activity;
int layoutResourceID;
ArrayList<BTLE_Device> devices;
public ListAdapter_BTLE_Devices(Activity activity, int resource, ArrayList<BTLE_Device> objects) {
super(activity.getApplicationContext(), resource, objects);
this.activity = activity;
layoutResourceID = resource;
devices = objects;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
if (convertView == null) {
LayoutInflater inflater =
(LayoutInflater) activity.getApplicationContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(layoutResourceID, parent, false);
}
BTLE_Device device = devices.get(position);
String rssi = String.valueOf (device.getRSSI());
String major = String.valueOf (device.getMajor());
String minor = String.valueOf (device.getMinor ());
String uuid = device.getUuid ();
TextView tv_major = (TextView)convertView.findViewById (R.id.tv_major);
TextView tv_minor = (TextView)convertView.findViewById (R.id.tv_minor);
TextView tv_uuid = (TextView)convertView.findViewById (R.id.tv_uuid);
TextView tv_rssi = (TextView)convertView.findViewById (R.id.tv_rssi);
tv_major.setText (major);
tv_minor.setText (minor);
tv_uuid.setText (uuid);
tv_rssi.setText (rssi);
return convertView;
}
}
最后是我的主要活动
public class MainActivity extends AppCompatActivity implements View.OnClickListener, AdapterView.OnItemClickListener {
//INITIALIZE VARIABLES
private final static String TAG = MainActivity.class.getSimpleName ( );
public static final int REQUEST_ENABLE_BT = 1;
private HashMap <String, BTLE_Device> mBTDevicesHashMap;
private ArrayList <BTLE_Device> mBTDevicesArrayList;
private ListAdapter_BTLE_Devices adapter;
private Button btn_addIncident;
private Button btn_Scan;
private Button btn_incidentlist;
private Button btn_scanMyBeacon;
private BroadcastReceiver_BTState mBTStateUpdateReceiver;
private Scanner_BTLE mBTLeScanner;
private static final int PERMISSION_REQUEST_COARSE_LOCATION = 456;
private Realm realm;
@Override
//ONCREATE
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//CHECK IF BL IS SUPPORTED ON DEVICE
if (!getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE)) {
Utils.toast(getApplicationContext(), "BLE not supported");
finish();
}
//REQUEST PERIMISSIONS ( BLUETOOTH & GPS )
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
requestPermissions(new String[]{Manifest.permission.ACCESS_COARSE_LOCATION}, PERMISSION_REQUEST_COARSE_LOCATION);
}
//INITIALIZE
mBTStateUpdateReceiver = new BroadcastReceiver_BTState(getApplicationContext());
mBTLeScanner = new Scanner_BTLE(this, 7500, -105);
mBTDevicesHashMap = new HashMap<>();
mBTDevicesArrayList = new ArrayList<>();
adapter = new ListAdapter_BTLE_Devices(this, R.layout.btle_device_list_item, mBTDevicesArrayList);
ListView listView = new ListView(this);
listView.setAdapter(adapter);
listView.setOnItemClickListener(this);
((ScrollView) findViewById(R.id.scrollView)).addView(listView);
//BUTTONS TO VARIABLE
btn_scanMyBeacon = (Button) findViewById(R.id.btn_scanMyBeacon);
btn_Scan = (Button) findViewById(R.id.btn_scan);
btn_incidentlist = (Button) findViewById(R.id.btn_incident_list_sort);
btn_addIncident = (Button) findViewById(R.id.btn_addIncident);
//ONCLICKLISTENERS
btn_Scan.setOnClickListener(this);
btn_scanMyBeacon.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
startScan();
}
});
btn_incidentlist.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent listIntent = new Intent(MainActivity.this,IncidentListActivity.class);
MainActivity.this.startActivity(listIntent);
}
});
btn_addIncident.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent myIntent = new Intent(MainActivity.this, Add_Incident.class);
MainActivity.this.startActivity(myIntent);
}
});
//REALM
try {
realm = Realm.getDefaultInstance ( ); // opens "myrealm.realm"
}
catch (Exception e) {
RealmConfiguration config = new RealmConfiguration.Builder ()
.deleteRealmIfMigrationNeeded ()
.build ();
realm.getInstance (config);
}
}
@Override
//ONSTART
protected void onStart() {
super.onStart();
registerReceiver(mBTStateUpdateReceiver, new IntentFilter(BluetoothAdapter.ACTION_STATE_CHANGED));
}
@Override
//ONRESUME
protected void onResume() {
super.onResume();
}
@Override
//ONPAUSE
protected void onPause() {
super.onPause();
stopScan();
}
@Override
//ONSTOP
protected void onStop() {
super.onStop();
unregisterReceiver(mBTStateUpdateReceiver);
stopScan();
}
@Override
//ONDESTROY
public void onDestroy() {
super.onDestroy();
realm.close();
}
@Override
//BLUETOOTH CHECK
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// Check which request we're responding to
if (requestCode == REQUEST_ENABLE_BT) {
// Make sure the request was successful
if (resultCode == RESULT_OK) {
Utils.toast(getApplicationContext(), "Thank you for turning on Bluetooth");
} else if (resultCode == RESULT_CANCELED) {
Utils.toast(getApplicationContext(), "Please turn on Bluetooth");
}
}
}
@Override
//ONCLICK SCAN BUTTON
public void onClick(View v) {
//Called when the scan button is clicked. v= clicked view
switch (v.getId()) {
case R.id.btn_scan:
Utils.toast(getApplicationContext(), "Scan Button Pressed");
if (!mBTLeScanner.isScanning()) {
startScan();
} else {
stopScan();
}
break;
default:
break;
}
}
//ADD DEVICE
/**
* Adds a device to the ArrayList and Hashmap that the ListAdapter is keeping track of.
*
* @param device the BluetoothDevice to be added
* @param rssi the rssi of the BluetoothDevice
*/
public void addDevice(BluetoothDevice device, int rssi, byte[] scanRecord, int major, int minor, String uuid) {
Log.d ("first add","Device"+ device.getAddress ()+"rssi" +rssi+"uuid"+uuid );
Log.d("HashMap",""+mBTDevicesHashMap.size());
Log.d("ArrayList",""+mBTDevicesArrayList.size());
if (!mBTDevicesHashMap.containsKey(uuid)) {
BTLE_Device btleDevice = new BTLE_Device(device);
btleDevice.setRSSI(rssi);
mBTDevicesHashMap.put(uuid, btleDevice);
mBTDevicesArrayList.add(btleDevice);
} else {
BTLE_Device current = mBTDevicesHashMap.get(uuid);
current.setRSSI(rssi);
current.setMajor(major);
current.setMinor(minor);
current.setUuid(uuid);
}
Log.d("HashMapAfter",""+mBTDevicesHashMap.size());
Log.d("ArrayListAfter",""+mBTDevicesArrayList.size());
adapter.notifyDataSetChanged();
}
//START SCAN
/**
* Clears the ArrayList and Hashmap the ListAdapter is keeping track of.
* Starts Scanner_BTLE.
* Changes the scan button text.
*/
public void startScan() {
btn_Scan.setText("Scanning...");
mBTDevicesArrayList.clear();
mBTDevicesHashMap.clear();
adapter.notifyDataSetChanged();
mBTLeScanner.start();
}
//STOP SCAN
/**
* Stops Scanner_BTLE
* Changes the scan button text.
*/
public void stopScan() {
btn_Scan.setText("Scan Again");
mBTLeScanner.stop();
for(int i=0; i<mBTDevicesArrayList.size();i++){
System.out.println (mBTDevicesArrayList.get(i).getUuid() );
}
}
/**
* Called when an item in the ListView is clicked.
*/
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
System.out.println ( );
}
}
答案 0 :(得分：0)
Jesper，您确信旁边有几个设备符合最低条件
if (((int) scanRecord[startByte + 2] & 0xff) == 0x02 &&
((int) scanRecord[startByte + 3] & 0xff) == 0x15)