我想在我的项目中实现一个时间表功能。所以我在谷歌上搜索了一个警报管理程序，但我找不到任何例子。
谁能帮我一个基本的警报管理程序?
当前回答
我尝试了XXX的解决方案，虽然它最初确实有效，但在某种程度上它停止了工作。onReceive再也没有被调用。我花了好几个小时想知道那是什么。我开始意识到，出于某种神秘的原因，意图不再被召唤。为了解决这个问题，我发现确实需要在清单中为接收者指定一个操作。例子:
<receiver android:name=".Alarm" android:exported="true">
<intent-filter>
<action android:name="mypackage.START_ALARM" >
</action>
</intent-filter>
</receiver>
请注意，名称是“。“Alarm”和周期。在XXX的setAlarm方法中，创建Intent，如下所示:
Intent i = new Intent("mypackage.START_ALARM");
START_ALARM消息可以是您想要的任何消息。我这样命名只是为了演示。
I have not seen receivers defined in the manifest without an intent filter that specifies the action. Creating them the way XXX has specified it seems kind of bogus. By specifying the action name, Android will be forced to create an instance of the BroadcastReceiver using the class that corresponds to the action. If you rely upon context, be aware that Android has several different objects that are ALL called context and may not result in getting your BroadcastReceiver created. Forcing Android to create an instance of your class using only the action message is far better than relying upon some iffy context that may never work.
其他回答
MainActivity.java
package com.example.alarmexample;
import android.app.Activity;
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class MainActivity extends Activity {
Button b1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
startAlert();
} public void startAlert() {
int timeInSec = 2;
Intent intent = new Intent(this, MyBroadcastReceiver.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(
this.getApplicationContext(), 234, intent, 0);
AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
alarmManager.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + (timeInSec * 1000), pendingIntent);
Toast.makeText(this, "Alarm set to after " + i + " seconds",Toast.LENGTH_LONG).show();
}
}
MyBroadcastReceiver.java
package com.example.alarmexample;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.media.MediaPlayer;
import android.widget.Toast;
public class MyBroadcastReceiver extends BroadcastReceiver {
MediaPlayer mp;
@Override
public void onReceive(Context context, Intent intent) {
mp=MediaPlayer.create(context, R.raw.alarm);
mp.start();
Toast.makeText(context, "Alarm", Toast.LENGTH_LONG).show();
}
}
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.alarmexample" >
<uses-permission android:name="android.permission.VIBRATE" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.example.alarmexample.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<receiver android:name="MyBroadcastReceiver" >
</receiver>
</application>
</manifest>
报警经理:
添加到XML布局(*初始化这些视图在创建在主活动)
<TimePicker
android:id="@+id/timepicker"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="2"></TimePicker>
<Button
android:id="@+id/btn_start"
android:text="start Alarm"
android:onClick="start_alarm_event"
android:layout_width="match_parent"
android:layout_height="52dp" />
添加到清单(内部应用程序标签&&外部活动)
<receiver android:name=".AlarmBroadcastManager"
android:enabled="true"
android:exported="true"/>
创建AlarmBroadcastManager类(从BroadcastReceiver继承)
public class AlarmBroadcastManager extends BroadcastReceiver{
@Override
public void onReceive(Context context, Intent intent) {
MediaPlayer mediaPlayer=MediaPlayer.create(context,Settings.System.DEFAULT_RINGTONE_URI);
mediaPlayer.start();
}
}
在Main Activity中(添加这些功能):
@RequiresApi(api = Build.VERSION_CODES.M)
public void start_alarm_event(View view){
Calendar calendar=Calendar.getInstance();
calendar.set(
calendar.get(Calendar.YEAR),
calendar.get(Calendar.MONTH),
calendar.get(Calendar.DAY_OF_MONTH),
timePicker.getHour(),
timePicker.getMinute(),
0
);
setAlarm(calendar.getTimeInMillis());
}
public void setAlarm(long timeInMillis){
AlarmManager alarmManager=(AlarmManager) getSystemService(Context.ALARM_SERVICE);
Intent intent=new Intent(this,AlarmBroadcastManager.class);
PendingIntent pendingIntent=PendingIntent.getBroadcast(this,0,intent,0);
alarmManager.setRepeating(AlarmManager.RTC_WAKEUP,timeInMillis,AlarmManager.INTERVAL_DAY,pendingIntent);
Toast.makeText(getApplicationContext(),"Alarm is Set",Toast.LENGTH_SHORT).show();
}
我在Android上也遇到了警报问题。问题是关于打盹模式(https://developer.android.com/training/monitoring-device-state/doze-standby)。例如，当我把闹钟调到一个小时后，它就正常了，但如果我把它调到凌晨4点，它就不工作了。我刚刚发现这是非常简单的，我只是应该使用AlarmManager.setAlarmClock()而不是AlarmManager.set()。
所以我决定在github上创建一个示例应用程序。 https://github.com/carlosabreu/androidalarm
•AlarmManager与IntentService结合使用
我认为使用AlarmManager的最佳模式是它与IntentService的协作。IntentService由AlarmManager触发，它通过接收意图处理所需的操作。这种结构不像使用BroadcastReceiver那样对性能有影响。我在kotlin中为这个想法开发了一个示例代码，可以在这里获得:
MyAlarmManager.kt
import android.app.AlarmManager
import android.app.PendingIntent
import android.content.Context
import android.content.Intent
object MyAlarmManager {
private var pendingIntent: PendingIntent? = null
fun setAlarm(context: Context, alarmTime: Long, message: String) {
val alarmManager: AlarmManager = context.getSystemService(Context.ALARM_SERVICE) as AlarmManager
val intent = Intent(context, MyIntentService::class.java)
intent.action = MyIntentService.ACTION_SEND_TEST_MESSAGE
intent.putExtra(MyIntentService.EXTRA_MESSAGE, message)
pendingIntent = PendingIntent.getService(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT)
alarmManager.set(AlarmManager.RTC_WAKEUP, alarmTime, pendingIntent)
}
fun cancelAlarm(context: Context) {
pendingIntent?.let {
val alarmManager: AlarmManager = context.getSystemService(Context.ALARM_SERVICE) as AlarmManager
alarmManager.cancel(it)
}
}
}
MyIntentService.kt
import android.app.IntentService
import android.content.Intent
class MyIntentService : IntentService("MyIntentService") {
override fun onHandleIntent(intent: Intent?) {
intent?.apply {
when (intent.action) {
ACTION_SEND_TEST_MESSAGE -> {
val message = getStringExtra(EXTRA_MESSAGE)
println(message)
}
}
}
}
companion object {
const val ACTION_SEND_TEST_MESSAGE = "ACTION_SEND_TEST_MESSAGE"
const val EXTRA_MESSAGE = "EXTRA_MESSAGE"
}
}
manifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.aminography.alarm">
<application
... >
<service
android:name="path.to.MyIntentService"
android:enabled="true"
android:stopWithTask="false" />
</application>
</manifest>
用法:
val calendar = Calendar.getInstance()
calendar.add(Calendar.SECOND, 10)
MyAlarmManager.setAlarm(applicationContext, calendar.timeInMillis, "Test Message!")
如果你想取消预定的闹钟，试试这个:
MyAlarmManager.cancelAlarm(applicationContext)
我已经用最简单的方式实现了这一点。
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import junit.framework.Assert;
/**
* Created by Daniel on 28/08/2016.
*/
public abstract class AbstractSystemServiceTask {
private final Context context;
private final AlarmManager alarmManager;
private final BroadcastReceiver broadcastReceiver;
private final PendingIntent pendingIntent;
public AbstractSystemServiceTask(final Context context, final String id, final long time, final AlarmType alarmType, final BackgroundTaskListener backgroundTaskListener) {
Assert.assertNotNull("ApplicationContext can't be null", context);
Assert.assertNotNull("ID can't be null", id);
this.context = context;
this.alarmManager = (AlarmManager) this.context.getSystemService(Context.ALARM_SERVICE);
this.context.registerReceiver(
this.broadcastReceiver = this.getBroadcastReceiver(backgroundTaskListener),
new IntentFilter(id));
this.configAlarmManager(
this.pendingIntent = PendingIntent.getBroadcast(this.context, 0, new Intent(id), 0),
time,
alarmType);
}
public void stop() {
this.alarmManager.cancel(this.pendingIntent);
this.context.unregisterReceiver(this.broadcastReceiver);
}
private BroadcastReceiver getBroadcastReceiver(final BackgroundTaskListener backgroundTaskListener) {
Assert.assertNotNull("BackgroundTaskListener can't be null.", backgroundTaskListener);
return new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
backgroundTaskListener.perform(context, intent);
}
};
}
private void configAlarmManager(final PendingIntent pendingIntent, final long time, final AlarmType alarmType) {
long ensurePositiveTime = Math.max(time, 0L);
switch (alarmType) {
case REPEAT:
this.alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis(), ensurePositiveTime, pendingIntent);
break;
case ONE_TIME:
default:
this.alarmManager.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + ensurePositiveTime, pendingIntent);
}
}
public interface BackgroundTaskListener {
void perform(Context context, Intent intent);
}
public enum AlarmType {
REPEAT, ONE_TIME;
}
}
唯一的下一步就是执行它。
import android.content.Context;
import android.content.Intent;
import android.util.Log;
import ...AbstractSystemServiceTask;
import java.util.concurrent.TimeUnit;
/**
* Created by Daniel on 28/08/2016.
*/
public class UpdateInfoSystemServiceTask extends AbstractSystemServiceTask {
private final static String ID = "UPDATE_INFO_SYSTEM_SERVICE";
private final static long REPEAT_TIME = TimeUnit.SECONDS.toMillis(10);
private final static AlarmType ALARM_TYPE = AlarmType.REPEAT;
public UpdateInfoSystemServiceTask(Context context) {
super(context, ID, REPEAT_TIME, ALARM_TYPE, new BackgroundTaskListener() {
@Override
public void perform(Context context, Intent intent) {
Log.i("MyAppLog", "-----> UpdateInfoSystemServiceTask");
//DO HERE WHATEVER YOU WANT...
}
});
Log.i("MyAppLog", "UpdateInfoSystemServiceTask started.");
}
}
我喜欢使用这个实现，但另一种可能的好方法是，不要使AbstractSystemServiceTask类抽象，而是通过Builder来构建它。
我希望它能帮助你。
更新 改进了允许同一个BroadCastReceiver上有多个BackgroundTaskListener。
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import junit.framework.Assert;
import java.util.HashSet;
import java.util.Set;
/**
* Created by Daniel on 28/08/2016.
*/
public abstract class AbstractSystemServiceTask {
private final Context context;
private final AlarmManager alarmManager;
private final BroadcastReceiver broadcastReceiver;
private final PendingIntent pendingIntent;
private final Set<BackgroundTaskListener> backgroundTaskListenerSet;
public AbstractSystemServiceTask(final Context context, final String id, final long time, final AlarmType alarmType) {
Assert.assertNotNull("ApplicationContext can't be null", context);
Assert.assertNotNull("ID can't be null", id);
this.backgroundTaskListenerSet = new HashSet<>();
this.context = context;
this.alarmManager = (AlarmManager) this.context.getSystemService(Context.ALARM_SERVICE);
this.context.registerReceiver(
this.broadcastReceiver = this.getBroadcastReceiver(),
new IntentFilter(id));
this.configAlarmManager(
this.pendingIntent = PendingIntent.getBroadcast(this.context, 0, new Intent(id), 0),
time,
alarmType);
}
public synchronized void registerTask(final BackgroundTaskListener backgroundTaskListener) {
Assert.assertNotNull("BackgroundTaskListener can't be null", backgroundTaskListener);
this.backgroundTaskListenerSet.add(backgroundTaskListener);
}
public synchronized void removeTask(final BackgroundTaskListener backgroundTaskListener) {
Assert.assertNotNull("BackgroundTaskListener can't be null", backgroundTaskListener);
this.backgroundTaskListenerSet.remove(backgroundTaskListener);
}
public void stop() {
this.backgroundTaskListenerSet.clear();
this.alarmManager.cancel(this.pendingIntent);
this.context.unregisterReceiver(this.broadcastReceiver);
}
private BroadcastReceiver getBroadcastReceiver() {
return new BroadcastReceiver() {
@Override
public void onReceive(final Context context, final Intent intent) {
for (BackgroundTaskListener backgroundTaskListener : AbstractSystemServiceTask.this.backgroundTaskListenerSet) {
backgroundTaskListener.perform(context, intent);
}
}
};
}
private void configAlarmManager(final PendingIntent pendingIntent, final long time, final AlarmType alarmType) {
long ensurePositiveTime = Math.max(time, 0L);
switch (alarmType) {
case REPEAT:
this.alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis(), ensurePositiveTime, pendingIntent);
break;
case ONE_TIME:
default:
this.alarmManager.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + ensurePositiveTime, pendingIntent);
}
}
public interface BackgroundTaskListener {
void perform(Context context, Intent intent);
}
public enum AlarmType {
REPEAT, ONE_TIME;
}
}
推荐文章
- 如何在Spring中定义List bean ?
- 将Set<T>转换为List<T>的最简洁的方法
- 在JavaScript中，什么相当于Java的Thread.sleep() ?
- Android选择器和文本颜色
- 使用Java重命名文件
- URL从Java中的类路径加载资源
- .toArray（new MyClass[0]） or .toArray（new MyClass[myList.size（）]）？
- Hibernate中不同的保存方法之间有什么区别?
- 视图绑定-我如何获得包含布局的绑定?
- 在Android Studio中改变矢量资产的填充颜色
- 在构建中编写注释的语法是什么?gradle文件?
- 如何以编程方式添加按钮色调
- 用Android Studio进行调试永远停留在“等待调试器”状态
- Java 8流和数组操作
- Java Regex捕获组
