传入的短信无法显示Toast消息

Question

我正在创建一个应用程序，只要设备收到传入的短信，就会发出一个toast消息，即使应用程序在后台运行它也应该显示一个Toast消息。

我在Marshmallow 6.0设备（Moto M）上测试我的应用程序。 使用Android Studio进行开发api 23 marshmallow。

MainActivity.java：

package android.broadcastreceiversms;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
}

使用广播接收器在同一目录中的IncomingSMS.java类文件：

package android.broadcastreceiversms;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.Build;
import android.os.Bundle;
import android.telephony.SmsMessage;
import android.util.Log;
import android.widget.Toast;

/**
 * Created by Mahesh on 09-01-2017.
 */

public class IncomingSms extends BroadcastReceiver {
    public void onReceive(Context context, Intent intent) {
        Bundle myBundle = intent.getExtras();
        SmsMessage[] messages = null;
        String strMessage = "";

        if (myBundle != null) {
            Object[] pdus = (Object[]) myBundle.get("pdus");

            messages = new SmsMessage[pdus.length];

            for (int i = 0; i < messages.length; i++) {
                    String format = myBundle.getString("format");
                    messages[i] = SmsMessage.createFromPdu((byte[]) pdus[i], format);

                strMessage += "SMS From: " + messages[i].getOriginatingAddress();
                strMessage += " : ";
                strMessage += messages[i].getMessageBody();
                strMessage += "\n";
            }

            Log.v("SMS", strMessage);
            Toast.makeText(context, strMessage, Toast.LENGTH_SHORT).show();
        }
    }
}

的AndroidManifest.xml：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="android.broadcastreceiversms">
    <uses-permission android:name="android.permission.RECEIVE_SMS"></uses-permission>
<uses-permission android:name="android.permission.READ_SMS" />
<uses-permission android:name="android.permission.SEND_SMS"></uses-permission>



    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>

            <receiver android:name=".IncomingSms">
                <intent-filter android:priority="500">
                    <action android:name="android.provider.Telephony.SMS_RECEIVED" />
                </intent-filter>
            </receiver>


        </activity>
    </application>

</manifest>