Android 广播接收器答案

【问题标题】：Android Broadcast ReceiverAndroid 广播接收器
【发布时间】：2013-07-30 08:39:21
【问题描述】：

我在我的应用程序中使用基于警报的应用程序我使用以下代码设置了警报。如果我创建警报意味着它的创建，但警报不会移动到广播接收器。我已经尝试了几次，但它对我不起作用。即使我已经在 android manifest 文件中正确添加了广播接收器。

1.设置闹钟类：

    public class Alertedit extends Activity {

   boolean AlarmEnabled;
   final static int RQS_1 = 1;
   TimePicker myTimePicker;

 private SQLiteConnectornew loginDataBaseAdapter;


        protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

      setContentView(R.layout.activity_alertaddlist);

     Button bt1 = (Button) findViewById(R.id.alerttime);

       bt1.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                openTimePickerDialog(false);
            }});}

            private void openTimePickerDialog(boolean is24r){
        Calendar calendar = Calendar.getInstance();

        timePickerDialog = new TimePickerDialog(
            Alertedit.this, 
            onTimeSetListener, 
            calendar.get(Calendar.HOUR_OF_DAY), 
            calendar.get(Calendar.MINUTE), 
            is24r);
        timePickerDialog.setTitle("Set Alarm Time");  

        timePickerDialog.show();}

        OnTimeSetListener onTimeSetListener
        = new OnTimeSetListener(){

        @Override
        public void onTimeSet(TimePicker view, int hourOfDay, int minute) {

            Calendar calNow = Calendar.getInstance();
            Calendar calSet = (Calendar) calNow.clone();

            calSet.set(Calendar.HOUR_OF_DAY, hourOfDay);
            calSet.set(Calendar.MINUTE, minute);
            calSet.set(Calendar.SECOND, 0);
            calSet.set(Calendar.MILLISECOND, 0);

            if(calSet.compareTo(calNow) <= 0){
                //Today Set time passed, count to tomorrow
                calSet.add(Calendar.DATE, 1);
            }

            setAlarm(calSet);
        }

        private void setAlarm(Calendar targetCal) {
            // TODO Auto-generated method stub
            bt1.setText("" + targetCal.getTime());
            Log.d("set", "Alarm set");
            Intent intent = new Intent(Alertedit.this,  AlarmReciever.class);
            PendingIntent pendingIntent = PendingIntent.getBroadcast(Alertedit.this, RQS_1, intent, 0);
            AlarmManager alarmManager = (AlarmManager)getSystemService(Context.ALARM_SERVICE);
            alarmManager.set(AlarmManager.RTC_WAKEUP, targetCal.getTimeInMillis(), pendingIntent);

        }};

2.接收器类：

public class AlarmReciever extends BroadcastReceiver {


@Override
public void onReceive(Context context, Intent intent) {
    try {
        /* Display an alert */
        Log.e("value", "how are you??");
        Toast.makeText(context, "How are you?", Toast.LENGTH_LONG).show();
     } 
     catch (Exception r) {
        Toast.makeText(context, "You were supposed to do something"
              +" now but I can't retrieve what it was.",
              Toast.LENGTH_SHORT).show();
        Log.e("ALARM_RECEIVER", r.toString());
     }
  }

}

3.清单文件：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.contactlist"
android:versionCode="1"
android:versionName="1.0" >

<uses-sdk
    android:minSdkVersion="7"
    android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.INTERNET"/>

<application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:screenOrientation="portrait"
    android:theme="@style/AppTheme" >
    <activity
        android:name="com.example.contactlist.Primemfrontpage"

        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
            <activity
        android:name="com.example.contactlist.Login"
        android:label="@string/app_name" >
    </activity>
            <activity
        android:name="com.example.contactlist.Registration"
        android:label="@string/app_name" >
    </activity>
     <activity
        android:name="com.example.contactlistnew.Alertedit"
        android:label="@string/app_name"
        android:theme="@android:style/Theme.Translucent.NoTitleBar" >
    </activity>

    <receiver android:name="com.example.contactlistnew.AlarmReceiver">
    </receiver></application></manifest>

【问题讨论】：

标签： android broadcast alarm

【解决方案1】：

看来你应该为你的接收器添加意图过滤器，如下所示

<receiver android:name="com.example.contactlistnew.AlarmReceiver">
  <intent-filter>
        <action android:name="android.alarm.demo.action" />
  </intent-filter>
</receiver>

【讨论】：

在我看来，警报只有在时间到时才会发送广播。
另外，您可以设置过去的闹钟时间。如果时间发生在过去，将立即触发警报。

【解决方案2】：

来自 BroadcastReceiver 的消息必须从你的 Intent 中读取，类似这样的

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.widget.Toast;

public class MyBroadcastReceiver extends BroadcastReceiver{

    @Override
    public void onReceive(Context context, Intent intent) {
        // TODO Auto-generated method stub

        // Extract data included in the Intent
        CharSequence intentData = intent.getCharSequenceExtra("message");   
        Toast.makeText(context, "Received the Intent's message: "+intentData, Toast.LENGTH_LONG).show();
    }

}

【讨论】：

【解决方案3】：

这对我有用。请在时间比当前时间提前 2 分钟时检查。

 public static final int REQUEST_CODE_RESTART_TIMER_TASK = 874378;

private void registerAlarm(Context applicationContext, int minute) {
        Calendar calendar = Calendar.getInstance();
        calendar.setTimeInMillis(System.currentTimeMillis());
        calendar.add(Calendar.MINUTE, minute);

        PendingIntent pendingIntent = getAlarmPendingIntent(applicationContext);
        AlarmManager alarmMgr1 = (AlarmManager) applicationContext.getSystemService(Context.ALARM_SERVICE);
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            alarmMgr1.setExactAndAllowWhileIdle(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(),
                    pendingIntent);

        } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
            alarmMgr1.setExact(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), pendingIntent);

        } else {
            alarmMgr1.set(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), pendingIntent);

        }
    }

这就是创建待处理意图的方法

private PendingIntent getAlarmPendingIntent(Context context) {
        Intent intents = new Intent(context, ServiceRestartReceiver.class);
        intents.setAction(ServiceRestartReceiver.ACTION_TIMER_TASK);
        return PendingIntent.getBroadcast(context, REQUEST_CODE_RESTART_TIMER_TASK,
                intents, PendingIntent.FLAG_UPDATE_CURRENT);
    }

这就是您取消此警报的方式

private void cancelAlarm(Context context) {
        PendingIntent pendingIntent = getAlarmPendingIntent(context);
        AlarmManager alarmMgr1 = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
        alarmMgr1.cancel(pendingIntent);
    }

广播接收器像

public class ServiceRestartReceiver extends BroadcastReceiver {

    public static final String ACTION_TIMER_TASK = "com.tracki.action.COUNTDOWN_TIMER";
    private static final String TAG = "ServiceRestartReceiver";

    @Override
    public void onReceive(Context context, Intent intent) {
        try {

            if (intent != null && intent.getAction() != null) {
                switch (intent.getAction()) {

                    case ACTION_TIMER_TASK:
                        // DO your stuff here
                        break;
                }
            }
        } catch (Exception e) {
            Log.e(TAG, "Exception occur inside ServiceRestartReceiver:onReceive(): " + e.getMessage());
        }
    }
}

清单文件

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.contactlist"
android:versionCode="1"
android:versionName="1.0" >

<uses-sdk
    android:minSdkVersion="7"
    android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.INTERNET"/>

<application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:screenOrientation="portrait"
    android:theme="@style/AppTheme" >
    <activity
        android:name="com.example.contactlist.Primemfrontpage"

        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
            <activity
        android:name="com.example.contactlist.Login"
        android:label="@string/app_name" >
    </activity>
            <activity
        android:name="com.example.contactlist.Registration"
        android:label="@string/app_name" >
    </activity>
     <activity
        android:name="com.example.contactlistnew.Alertedit"
        android:label="@string/app_name"
        android:theme="@android:style/Theme.Translucent.NoTitleBar" >
    </activity>

    <receiver
            android:name=".ServiceRestartReceiver"
            android:exported="false" />
</application>
</manifest>

【讨论】：