BroadcastReceiver的BOOT_COMPLETED后不工作 [英] BroadcastReceiver not working after BOOT_COMPLETED
问题描述
我试图拦截来袭短信右boot_completed之后，但我在使用这一行NullPointerException异常的问题：
I'm trying to intercept incoming SMS right after boot_completed but i'm having a problem with a NullPointerException in this line:
Object[] rawMsgs=(Object[])intent.getExtras().get("pdus");
下面是我的清单：
Here's my manifest:
<uses-permission android:name="android.permission.SEND_SMS"></uses-permission>
<uses-permission android:name="android.permission.RECEIVE_SMS"></uses-permission>
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"></uses- permission>
<uses-permission android:name="android.permission.INTERNET"></uses-permission>
<uses-permission android:name="android.permission.READ_PHONE_STATE"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<application android:icon="@drawable/icon" android:label="@string/app_name" android:theme="@android:style/Theme.NoTitleBar">
<receiver android:name=".SMSReceiver"
android:permission="android.permission.BROADCAST_SMS"
>
<intent-filter android:priority="1000">
<action android:name="android.provider.Telephony.SMS_RECEIVED"></action>
<action android:name="android.intent.action.BOOT_COMPLETED"></action>
</intent-filter>
</receiver>
</application>
接收器：
public class SMSReceiver extends BroadcastReceiver
{
private final LocationListener locationListener = new LocationListener() {
public void onLocationChanged(Location location) {
}
public void onProviderDisabled(String provider){}
public void onProviderEnabled(String provider) {}
public void onStatusChanged(String provider, int status, Bundle extras) {}
};
@Override
public void onReceive(Context context, Intent intent) {
LocationManager lm = (LocationManager)context.getSystemService(Context.LOCATION_SERVICE);
//Get as fine grained location as possible, while saving battery life.
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
criteria.setAltitudeRequired(false);
criteria.setBearingRequired(false);
criteria.setCostAllowed(true);
criteria.setPowerRequirement(Criteria.POWER_LOW);
String provider = lm.getBestProvider(criteria, true);
Toast toast3 = Toast.makeText(context, "Provider: "+provider, Toast.LENGTH_LONG);
toast3.show();
Object[] rawMsgs=(Object[])intent.getExtras().get("pdus");
for (Object raw : rawMsgs) {
SmsMessage msg=SmsMessage.createFromPdu((byte[])raw);
SmsManager sms = SmsManager.getDefault();
if (msg.getMessageBody().toUpperCase().contains("LOC")) {
Log.w("SMS:"+msg.getOriginatingAddress(),
msg.getMessageBody());
Toast toast1 = Toast.makeText(context, "Phone Number: "+msg.getOriginatingAddress()+" Message: "+msg.getMessageBody(), Toast.LENGTH_LONG);
toast1.show();
abortBroadcast();
if(provider!=null){
lm.requestLocationUpdates(provider, 0, 0, locationListener);
if(lm != null)
{
Location last_good = lm.getLastKnownLocation(provider);
if(last_good != null)
{
Toast.makeText(context, "Got Message from " + msg.getOriginatingAddress() + " , Sending" + last_good.toString(), Toast.LENGTH_SHORT).show();
//sendSMS(msg.getOriginatingAddress(), "http://maps.google.com?q=" + last_good.convert(last_good.getLatitude(), Location.FORMAT_DEGREES) + "," + last_good.convert(last_good.getLongitude(), Location.FORMAT_DEGREES), context);
//sendSMS(msg.getOriginatingAddress(), last_good.getLatitude() + "," + last_good.getLongitude(), context);
sms.sendTextMessage(msg.getOriginatingAddress(), null, last_good.getLatitude() + "," + last_good.getLongitude(), null, null);
lm.removeUpdates(locationListener);
}
else
{
lm.removeUpdates(locationListener);
sendSMS(msg.getOriginatingAddress(),"Location Not Available. Possible Reasons: Phone is Off, GPS is Off, No Satellites in sight", context);
}
}
}
else{
sendSMS(msg.getOriginatingAddress(),"Location Not Available. Possible Reasons: Phone is Off, GPS is Off, No Satellites in sight", context);
}
}
}
}
感谢。
推荐答案
这里的问题是，你的BroadcastReceiver实现已经映射到两个目的 - android.provider.Telephony.SMS_RECEIVED 和 android.intent.action.BOOT_COMPLETED - 但在执行的onReceive你不检查其意图正在处理
The problem here is that your BroadcastReceiver implementation has been mapped to two intents - android.provider.Telephony.SMS_RECEIVED and android.intent.action.BOOT_COMPLETED - but in the onReceive implementation you're not checking which intent you are processing.
我的的猜测的是 android.intent.action.BOOT_COMPLETED 已收到， intent.getExtras（）则返回null。你可以通过添加一些日志记录的方法，看的logcat窗口（如果你使用Eclipse）证实了这一点。
My guess is that android.intent.action.BOOT_COMPLETED has been received and intent.getExtras() is returning null. You could confirm this by adding some logging to the method and watching the logcat window (if you're using Eclipse).
如果你写了一个服务或广播接收器，并将其映射到多个意图是很好的做法 - 不必需的 - 要检查其意图已收到，并适当地处理它。个人而言，我会去是这样的：
If you write a service or broadcast receiver and map it to multiple intents it is good practice - nay essential - to check which intent has been received and process it appropriately. Personally I'd go for something like this:
if (intent.getAction().equals("android.intent.action.BOOT_COMPLETED")) {
// boot-related processing here
}
else if (intent.getAction().equals("android.provider.Telephony.SMS_RECEIVED")) {
// SMS-related processing here
}
else {
// intent not handled - log as a warning as you've registered to receive it
}
您可以不承担故障安全的行为。为了清楚起见，将意图处理逻辑到一个单独的方法：
You can't assume fail-safe behaviour. For clarity, move the intent processing logic into a separate method:
if (intent.getAction().equals("android.intent.action.BOOT_COMPLETED")) {
processBootCompletedIntent(intent);
}
else if (intent.getAction().equals("android.provider.Telephony.SMS_RECEIVED")) {
processSmsReceivedIntent(intent);
}
else {
// intent not handled - log as a warning as you've registered to receive it
}
PS - 大部分（如果不是全部）'本土'的意图操作字符串保持在一个相关类的常量。例如android.intent.action.BOOT_COMPLETED被定义为Intent.ACTION_BOOT_COMPLETED。使用如存在常数，它可以节省你做任何输入错误。
PS - most (if not all) 'native' intent action strings are held as constants in a relevant class. For example android.intent.action.BOOT_COMPLETED is defined as Intent.ACTION_BOOT_COMPLETED. Use the constants where they exist, it'll save you making any typing errors.
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