android - 在没有服务的情况下使用 AlarmManager

Question

是否可以在应用程序不使用服务的情况下使用 AlarmManager 运行警报。 AlarmManager 必须让设备退出 sleep 模式并在 onReceive 中执行我的代码。实际上，我在这里看到的每个代码示例都显示了正在使用的服务。然而，Android 文档并未提及需要提供服务。

Answer 1

这是一个工作示例，

activity_alarm_manager.xml文件的代码

<linearlayout android:layout_height="match_parent"
   android:layout_width="match_parent" android:orientation="vertical"
   xmlns:android="http://schemas.android.com/apk/res/android"
   xmlns:tools="http://schemas.android.com/tools">

   <button android:id="@+id/btStart" android:layout_height="wrap_content"
     android:layout_width="match_parent" android:onclick="startRepeatingTimer"
     android:padding="@dimen/padding_medium" android:text="@string/btStart"  
     tools:context=".WidgetAlarmManagerActivity"/>
   <button android:id="@+id/btCancel" android:layout_height="wrap_content"
     android:layout_width="match_parent" android:onclick="cancelRepeatingTimer" 
     android:padding="@dimen/padding_medium" android:text="@string/btCancel"
     tools:context=".WidgetAlarmManagerActivity"/>
    <button android:id="@+id/btOneTime" android:layout_height="wrap_content"
    android:layout_width="match_parent" android:onclick="onetimeTimer"
    android:padding="@dimen/padding_medium" android:text="@string/btOneTime"  
    tools:context=".WidgetAlarmManagerActivity"/>
  </linearlayout>

BroadcastReceiver的代码，

public class AlarmManagerBroadcastReceiver extends BroadcastReceiver {

 final public static String ONE_TIME = "onetime";

 @Override
 public void onReceive(Context context, Intent intent) {
   PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
         PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "YOUR TAG");
         //Acquire the lock
         wl.acquire();

         //You can do the processing here.
         Bundle extras = intent.getExtras();
         StringBuilder msgStr = new StringBuilder();

         if(extras != null && extras.getBoolean(ONE_TIME, Boolean.FALSE)){
          //Make sure this intent has been sent by the one-time timer button.
          msgStr.append("One time Timer : ");
         }
         Format formatter = new SimpleDateFormat("hh:mm:ss a");
         msgStr.append(formatter.format(new Date()));

         Toast.makeText(context, msgStr, Toast.LENGTH_LONG).show();

         //Release the lock
         wl.release();
 }

 public void SetAlarm(Context context)
    {
        AlarmManager am=(AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
        Intent intent = new Intent(context, AlarmManagerBroadcastReceiver.class);
        intent.putExtra(ONE_TIME, Boolean.FALSE);
        PendingIntent pi = PendingIntent.getBroadcast(context, 0, intent, 0);
        //After after 5 seconds
        am.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis(), 1000 * 5 , pi);
    }

    public void CancelAlarm(Context context)
    {
        Intent intent = new Intent(context, AlarmManagerBroadcastReceiver.class);
        PendingIntent sender = PendingIntent.getBroadcast(context, 0, intent, 0);
        AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
        alarmManager.cancel(sender);
    }

    public void setOnetimeTimer(Context context){
     AlarmManager am=(AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
        Intent intent = new Intent(context, AlarmManagerBroadcastReceiver.class);
        intent.putExtra(ONE_TIME, Boolean.TRUE);
        PendingIntent pi = PendingIntent.getBroadcast(context, 0, intent, 0);
        am.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis(), pi);
    }
}

AndroidManifest.xml的代码

<manifest android:versioncode="1" android:versionname="1.0"
       package="com.rakesh.alarmmanagerexample"
       xmlns:android="http://schemas.android.com/apk/res/android">

   <uses-sdk android:minsdkversion="10" android:targetsdkversion="15"/>
   <uses-permission android:name="android.permission.WAKE_LOCK"/>
    <application android:icon="@drawable/ic_launcher"
       android:label="@string/app_name" android:theme="@style/AppTheme">
        <activity android:label="@string/title_activity_alarm_manager"
           android:name="com.rakesh.alarmmanagerexample.AlarmManagerActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER" />
          </intent-filter>
        </activity>
        <receiver android:name="com.rakesh.alarmmanagerexample.AlarmManagerBroadcastReceiver">
        </receiver>
    </application>
</manifest>

AlarmManagerActivity.java文件的代码

public class AlarmManagerActivity extends Activity {

 private AlarmManagerBroadcastReceiver alarm;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_alarm_manager);
        alarm = new AlarmManagerBroadcastReceiver();
    }

    @Override
 protected void onStart() {
  super.onStart();
 }

    public void startRepeatingTimer(View view) {
     Context context = this.getApplicationContext();
     if(alarm != null){
      alarm.SetAlarm(context);
     }else{
      Toast.makeText(context, "Alarm is null", Toast.LENGTH_SHORT).show();
     }
    }

    public void cancelRepeatingTimer(View view){
     Context context = this.getApplicationContext();
     if(alarm != null){
      alarm.CancelAlarm(context);
     }else{
      Toast.makeText(context, "Alarm is null", Toast.LENGTH_SHORT).show();
     }
    }

    public void onetimeTimer(View view){
     Context context = this.getApplicationContext();
     if(alarm != null){
      alarm.setOnetimeTimer(context);
     }else{
      Toast.makeText(context, "Alarm is null", Toast.LENGTH_SHORT).show();
     }
    }

 @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_widget_alarm_manager, menu);
        return true;
    }
}

来自 Github 的引用链接