如何在广播接收机中获取短信数据

Question

    btnSend.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            try {
                String SENT = "sent";
                String DELIVERED = "delivered";
                Intent sentIntent = new Intent(SENT);

                /*Create Pending Intents*/
                PendingIntent sentPI = PendingIntent.getBroadcast(
                        getApplicationContext(), 0, sentIntent,
                        PendingIntent.FLAG_UPDATE_CURRENT);

                /* Register for SMS send action */
                registerReceiver(new BroadcastReceiver() {
                    @Override
                    public void onReceive(Context context, Intent intent) {
                        try {
      --->                  **SmsMessage[] smsMessage = Telephony.Sms.Intents.getMessagesFromIntent(intent);**
                            String messageBody = smsMessage[0].getMessageBody();
                        } catch (Exception e) {
                            e.printStackTrace();
                        }
                        int resultcode = getResultCode();
                        Log.d("  RESULT=", Integer.toString(resultcode));
                    }

                }, new IntentFilter(SENT));

                SmsManager smsManager = SmsManager.getDefault();

                if ((ContextCompat.checkSelfPermission(getApplicationContext(),
                        Manifest.permission.SEND_SMS) !=
                        PackageManager.PERMISSION_GRANTED) ||
                        (ContextCompat.checkSelfPermission(getApplicationContext(),
                                Manifest.permission.RECEIVE_SMS) !=
                                PackageManager.PERMISSION_GRANTED)){
                    ActivityCompat.requestPermissions(SMSActivity.this,
                            new String[] {
                                    Manifest.permission.SEND_SMS, Manifest.permission.RECEIVE_SMS
                            }, 1);
                }
                smsManager.sendTextMessage(phoneNo.getText().toString(), null,
                                                msg.getText().toString(), sentPI, null);
            } catch (Exception ex) {
                Toast.makeText(getApplicationContext(),
                        ex.getMessage(), Toast.LENGTH_LONG)
                        .show();
                ex.printStackTrace();
            }
        }
    });

W/System.err: java.lang.NullPointerException: Attempt to get length of null array
W/System.err:     at android.provider.Telephony$Sms$Intents.getMessagesFromIntent(Telephony.java:1345)
W/System.err:     at com.jdot.jsontest.SMSActivity$1$1.onReceive(SMSActivity.java:60)
W/System.err:     at android.app.LoadedApk$ReceiverDispatcher$Args.run(LoadedApk.java:993)
W/System.err:     at android.os.Handler.handleCallback(Handler.java:739)
W/System.err:     at android.os.Handler.dispatchMessage(Handler.java:95)
W/System.err:     at android.os.Looper.loop(Looper.java:158)
W/System.err:     at android.app.ActivityThread.main(ActivityThread.java:7224)
W/System.err:     at java.lang.reflect.Method.invoke(Native Method)
W/System.err:     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230)
W/System.err:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)

<uses-permission android:name="android.permission.SEND_SMS" />
<uses-permission android:name="android.permission.RECEIVE_SMS" />

<receiver android:name="MyBroadcastListener">
<intent-filter>
<action android:name="android.provider.Telephony.SMS_RECEIVED" />
</intent-filter>
</receiver>

Bundle bundle = intent.getExtras();
SmsMessage[] msgs = null;
String str = "";
if (bundle != null) {
 //---retrieve the SMS message received---
 Object[] pdus = (Object[]) bundle.get("pdus");
 msgs = new SmsMessage[pdus.length];
 for (int i=0; i<msgs.length; i++){
      msgs[i] = SmsMessage.createFromPdu((byte[])pdus[i]);
      str += "SMS from " + msgs[i].getOriginatingAddress();
              str += " :";
              str += msgs[i].getMessageBody().toString();
              str += "\n";
    }
//---display the new SMS message---
     Toast.makeText(context, str, Toast.LENGTH_SHORT).show();
}

1. 清单中是否需要receiver/intent-filter块，如果需要，如何在第一行中命名侦听器？
2. 在onReceive（）中无法收到传入消息副本的可能原因是什么？我应该做些什么来更正它？
3. 我是否需要发送消息并在onReceive（）中“捕获它”以便可靠地获得设备的电话号码，或者我是否可以从用户那里请求读取SMS的权限，然后只需读取第一条消息即可获得传入的电话号码？

请注意，我已经通读了所有类似的问题，还没有找到答案。

Answer 1

registerReceiver(..., new IntentFilter(SENT));

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