我已完全按照AltBeacon' reference app及其教程中的步骤对我的应用进行前景和后台的iBeacon检测。
实际上，我的应用确实检测到了iBeacons。我会在检测到iBeacon后发送通知。
然而，无论我的应用程序处于前台还是后台（特别是当设备被锁定时），测距过程可能会在几分钟后突然停止。
有时，我会在重新开启设备中的蓝牙后重启检测（i），（ii）重新启动应用程序后。但有时它不会。
我在我的应用程序的自定义应用程序中实现了BootstrapNotifier和RangeNotifier。以下是一些代码片段
MyApplication.java
public class MyApplication extends Application implements BootstrapNotifier, RangeNotifier {
private static final String TAG = "MyApplication";
private RegionBootstrap regionBootstrap;
private BackgroundPowerSaver backgroundPowerSaver;
private int notificationID = 0;
@Override
public void onCreate() {
super.onCreate();
BeaconManager beaconManager = BeaconManager.getInstanceForApplication(this);
beaconManager.getBeaconParsers().add(new BeaconParser().setBeaconLayout("m:2-3=0215,i:4-19,i:20-21,i:22-23,p:24-24"));
beaconManager.setBackgroundScanPeriod(1100l);
beaconManager.setBackgroundBetweenScanPeriod(1100l);
Region region = new Region("MyRegion", null, null, null);
regionBootstrap = new RegionBootstrap(this, region);
backgroundPowerSaver = new BackgroundPowerSaver(this);
}
@Override
public void didEnterRegion(Region region) {
BeaconManager.getInstanceForApplication(this).setRangeNotifier(this);
try {
BeaconManager.getInstanceForApplication(this).startRangingBeaconsInRegion(region);
}
catch (RemoteException e) {
Log.e(TAG, "Can't start ranging");
}
}
@Override
public void didExitRegion(Region region) {
}
@Override
public void didDetermineStateForRegion(int i, Region region) {
}
private void sendNotification(Beacon beacon) {
String message = beacon.getId3().toString();
NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(this).setSmallIcon(R.drawable.ic_launcher).setContentTitle("Where")
.setContentText(message).setAutoCancel(true);
Intent intent = new Intent(this, RDMainActivity.class);
intent.putExtra("Beacon", beacon);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_SINGLE_TOP);
PendingIntent resultPendingIntent = PendingIntent.getActivity(getApplicationContext(), notificationID, intent, PendingIntent.FLAG_CANCEL_CURRENT);
mBuilder.setContentIntent(resultPendingIntent);
NotificationManager mNotificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
mNotificationManager.notify(notificationID++, mBuilder.build());
}
@Override
public void didRangeBeaconsInRegion(Collection<Beacon> beacons, Region region) {
for (Beacon beacon : beacons) {
sendNotification(beacon);
}
}
我的测试设备是带有Android4.4.4的Nexus 7（2013移动版）
有没有人对这个问题有任何想法？任何帮助将不胜感激。
更新：这是我在前景中最后一次检测后的logcat
02-06 20:25:28.795 19482-19482/com.myapp D/BluetoothAdapter﹕ stopLeScan()
02-06 20:25:28.815 19482-19482/com.myapp W/CycledLeScanner﹕ Internal Android exception scanning for beacons
java.lang.NullPointerException
at android.os.Parcel.readException(Parcel.java:1471)
at android.os.Parcel.readException(Parcel.java:1419)
at android.bluetooth.IBluetoothGatt$Stub$Proxy.stopScan(IBluetoothGatt.java:771)
at android.bluetooth.BluetoothAdapter$GattCallbackWrapper.stopLeScan(BluetoothAdapter.java:1819)
at android.bluetooth.BluetoothAdapter.stopLeScan(BluetoothAdapter.java:1722)
at org.altbeacon.beacon.service.scanner.CycledLeScannerForJellyBeanMr2.finishScan(CycledLeScannerForJellyBeanMr2.java:67)
at org.altbeacon.beacon.service.scanner.CycledLeScanner.finishScanCycle(CycledLeScanner.java:249)
at org.altbeacon.beacon.service.scanner.CycledLeScanner.scheduleScanCycleStop(CycledLeScanner.java:234)
at org.altbeacon.beacon.service.scanner.CycledLeScanner$1.run(CycledLeScanner.java:230)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5001)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
at dalvik.system.NativeStart.main(Native Method)
02-06 20:25:29.936 19482-19482/com.myapp D/BluetoothAdapter﹕ stopLeScan()
02-06 20:25:29.936 19482-19482/com.myapp D/BluetoothAdapter﹕ startLeScan(): null
02-06 20:25:29.956 19482-19493/com.myapp D/BluetoothAdapter﹕ onClientRegistered() - status=0 clientIf=8
02-06 20:25:31.087 19482-19482/com.myapp D/BluetoothAdapter﹕ stopLeScan()
02-06 20:25:31.097 19482-19482/com.myapp W/CycledLeScanner﹕ Internal Android exception scanning for beacons
java.lang.NullPointerException
at android.os.Parcel.readException(Parcel.java:1471)
at android.os.Parcel.readException(Parcel.java:1419)
at android.bluetooth.IBluetoothGatt$Stub$Proxy.stopScan(IBluetoothGatt.java:771)
at android.bluetooth.BluetoothAdapter$GattCallbackWrapper.stopLeScan(BluetoothAdapter.java:1819)
at android.bluetooth.BluetoothAdapter.stopLeScan(BluetoothAdapter.java:1722)
at org.altbeacon.beacon.service.scanner.CycledLeScannerForJellyBeanMr2.finishScan(CycledLeScannerForJellyBeanMr2.java:67)
at org.altbeacon.beacon.service.scanner.CycledLeScanner.finishScanCycle(CycledLeScanner.java:249)
at org.altbeacon.beacon.service.scanner.CycledLeScanner.scheduleScanCycleStop(CycledLeScanner.java:234)
at org.altbeacon.beacon.service.scanner.CycledLeScanner$1.run(CycledLeScanner.java:230)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5001)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
at dalvik.system.NativeStart.main(Native Method)
02-06 20:25:32.218 19482-19482/com.myapp D/BluetoothAdapter﹕ stopLeScan()
02-06 20:25:32.218 19482-19482/com.myapp D/BluetoothAdapter﹕ startLeScan(): null
02-06 20:25:32.228 19482-19493/com.myapp D/BluetoothAdapter﹕ onClientRegistered() - status=0 clientIf=9
02-06 20:25:33.360 19482-19482/com.myapp D/BluetoothAdapter﹕ stopLeScan()
02-06 20:25:33.370 19482-19482/com.myapp W/CycledLeScanner﹕ Internal Android exception scanning for beacons
java.lang.NullPointerException
at android.os.Parcel.readException(Parcel.java:1471)
at android.os.Parcel.readException(Parcel.java:1419)
at android.bluetooth.IBluetoothGatt$Stub$Proxy.stopScan(IBluetoothGatt.java:771)
at android.bluetooth.BluetoothAdapter$GattCallbackWrapper.stopLeScan(BluetoothAdapter.java:1819)
at android.bluetooth.BluetoothAdapter.stopLeScan(BluetoothAdapter.java:1722)
at org.altbeacon.beacon.service.scanner.CycledLeScannerForJellyBeanMr2.finishScan(CycledLeScannerForJellyBeanMr2.java:67)
at org.altbeacon.beacon.service.scanner.CycledLeScanner.finishScanCycle(CycledLeScanner.java:249)
at org.altbeacon.beacon.service.scanner.CycledLeScanner.scheduleScanCycleStop(CycledLeScanner.java:234)
at org.altbeacon.beacon.service.scanner.CycledLeScanner$1.run(CycledLeScanner.java:230)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5001)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
at dalvik.system.NativeStart.main(Native Method)
02-06 20:25:34.521 19482-19482/com.myapp D/BluetoothAdapter﹕ stopLeScan()
02-06 20:25:34.521 19482-19482/com.myapp D/BluetoothAdapter﹕ startLeScan(): null
02-06 20:25:34.551 19482-19493/com.myapp D/BluetoothAdapter﹕ onClientRegistered() - status=133 clientIf=0
02-06 20:25:35.652 19482-19482/com.myapp D/BluetoothAdapter﹕ stopLeScan()