我有两部安卓5.0.2的手机，它们都安装了最新的Radius Beacon应用程序：Locate Beacon。同时，我打开了两个iBeacon发送器，并使用该应用程序在两台手机上看到RSSI不断变化。
但当我尝试编写一些示例代码来模拟上述情况时，我发现BLE扫描回调总是在调用2或3次后停止调用。我最初怀疑“Locate Beacon”可能使用了不同的方法，因此我尝试了两种API，一种是旧版本4.4的API，另一种是Android 5中引入的新方法，但两者都表现相同（但都运行在安卓5上）。
4.4的API:
但当我尝试编写一些示例代码来模拟上述情况时，我发现BLE扫描回调总是在调用2或3次后停止调用。我最初怀疑“Locate Beacon”可能使用了不同的方法，因此我尝试了两种API，一种是旧版本4.4的API，另一种是Android 5中引入的新方法，但两者都表现相同（但都运行在安卓5上）。
4.4的API:
public class MainActivity extends Activity {
private BluetoothAdapter mBluetoothAdapter;
private static final String LOG_TAG = "BleCollector";
private TextView calledTimesTextView = null;
private int calledTimes = 0;
// Device scan callback.
private BluetoothAdapter.LeScanCallback mLeScanCallback = new BluetoothAdapter.LeScanCallback() {
@Override
public void onLeScan(final BluetoothDevice device, int rssi,
byte[] scanRecord) {
calledTimes++;
runOnUiThread(new Runnable() {
@Override
public void run() {
calledTimesTextView.setText(Integer.toString(calledTimes));
}
});
Log.e(LOG_TAG, "in onScanResult, " + " is coming...");
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
calledTimesTextView = (TextView) findViewById(R.id.CalledTimes);
mBluetoothAdapter = ((BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE))
.getAdapter();
mBluetoothAdapter.startLeScan(mLeScanCallback);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}}
还有5.0.2版本：
public class MainActivity extends Activity {
private BluetoothAdapter mBluetoothAdapter = null;
private BluetoothLeScanner mLescanner;
private ScanCallback mLeScanCallback;
private static final String LOG_TAG = "BleFingerprintCollector";
private TextView calledTimesTextView = null;
private int calledTimes = 0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
calledTimesTextView = (TextView) findViewById(R.id.CalledTimes);
this.mBluetoothAdapter = ((BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE))
.getAdapter();
this.mLescanner = this.mBluetoothAdapter.getBluetoothLeScanner();
ScanSettings bleScanSettings = new ScanSettings.Builder().setScanMode(
ScanSettings.SCAN_MODE_LOW_LATENCY).build();
this.mLeScanCallback = new ScanCallback() {
@Override
public void onScanResult(int callbackType, ScanResult result) {
calledTimes++;
runOnUiThread(new Runnable() {
@Override
public void run() {
calledTimesTextView.setText(Integer
.toString(calledTimes));
}
});
Log.e(LOG_TAG, "in onScanResult, " + " is coming...");
}
@Override
public void onBatchScanResults(List<ScanResult> results) {
}
@Override
public void onScanFailed(int errorCode) {
}
};
this.mLescanner.startScan(null, bleScanSettings, this.mLeScanCallback);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}}
这些功能非常简单，只在用户界面显示计数器，并最终始终停在2或3。
我之前在一台装有Android 4.4的三星Note 2上尝试过接收BLE广告，它表现得非常完美，回调函数每秒钟被调用一次。 那么有人可以帮忙吗？为什么Radius' Locate Beacon在这里能够很好地工作？
BluetoothLeScanner.stopScan();Thread.Sleep(1100);BluetoothLeScanner.startScan()，是这样吗？ - Shawn