现在普遍的手机都会有一个闹钟的功能，如果使用Android来实现一个闹钟可以使用AtarmManager来实现。AtarmManager提供了一种系统级的提示服务，允许你安排在将来的某个时间执行一个服务。AlarmManager对象一般不直接实例化，而是通过Context.getsystemservice(Context.ALARM_SERVICE）方法获得。

下面是我们运用之前用到的TimePickerDialog结合AlarmManager，实现一个可以设定任意时间而且可以重复的闹钟，演示效果如下（大概每晚23:48会有闹钟通知）：

layout中activity_main.xml布局文件代码：

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <LinearLayout
 3     xmlns:android="http://schemas.android.com/apk/res/android"
 4     xmlns:tools="http://schemas.android.com/tools"
 5     android:id="@+id/activity_main"
 6     android:layout_width="match_parent"
 7     android:layout_height="match_parent"
 8     android:orientation="vertical"
 9     tools:context="com.example.administrator.alarmdemo.MainActivity">
10     <TextView
11         android:id="@+id/time_tv"
12         android:layout_width="match_parent"
13         android:layout_height="wrap_content"
14         android:hint="请设置闹铃时间"
15         android:clickable="true"
16         android:onClick="setTime"
17         android:gravity="center"/>
18     <TextView
19         android:id="@+id/time_tv2"
20         android:layout_width="match_parent"
21         android:layout_height="wrap_content"
22         android:hint="请设置响铃间隔时间"
23         android:clickable="true"
24         android:onClick="setIntervalTime"
25         android:gravity="center"/>
26     <Button
27         android:layout_width="match_parent"
28         android:layout_height="wrap_content"
29         android:onClick="open"
30         android:text="开启闹钟"/>
31     <Button
32         android:layout_width="match_parent"
33         android:layout_height="wrap_content"
34         android:onClick="stop"
35         android:text="结束闹钟"/>
36 </LinearLayout>

AndroidMainfest.xml配置文件（添加自定义重复闹铃receiver）：

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
 3     package="com.example.administrator.alarmdemo">
 4     <application
 5         android:allowBackup="true"
 6         android:icon="@mipmap/ic_launcher"
 7         android:label="@string/app_name"
 8         android:supportsRtl="true"
 9         android:theme="@style/AppTheme">
10         <activity android:name=".MainActivity">
11             <intent-filter>
12                 <action android:name="android.intent.action.MAIN" />
13 
14                 <category android:name="android.intent.category.LAUNCHER" />
15             </intent-filter>
16         </activity>
17         <receiver
18             android:name=".RepeatAlarmReceiver"
19             android:enabled="true"
20             android:exported="true">
21             <intent-filter>
22                 <action android:name="repeatAlarm" />
23             </intent-filter>
24         </receiver>
25         <activity android:name=".Main2Activity"></activity>
26     </application>
27 
28 </manifest>

RepeatAlarmReceiver.java广播接收文件：

 1 import android.content.BroadcastReceiver;
 2 import android.content.Context;
 3 import android.content.Intent;
 4 import android.widget.Toast;
 5 
 6 public class RepeatAlarmReceiver extends BroadcastReceiver {
 7     public RepeatAlarmReceiver() {
 8     }
 9     @Override
10     public void onReceive(Context context, Intent intent) {
11         Toast.makeText(context, "重复闹钟", Toast.LENGTH_SHORT).show();
12     }
13 }

MainActivity.java代码实现：

 1 import android.app.AlarmManager;
 2 import android.app.PendingIntent;
 3 import android.app.TimePickerDialog;
 4 import android.content.Intent;
 5 import android.provider.Settings;
 6 import android.support.v7.app.AppCompatActivity;
 7 import android.os.Bundle;
 8 import android.view.View;
 9 import android.widget.TextView;
10 import android.widget.TimePicker;
11 import java.util.Calendar;
12 public class MainActivity extends AppCompatActivity {
13     AlarmManager alarmManagerSet;
14     PendingIntent pendingIntentSet;
15     int myHour,myMinute;//声明响铃时间
16     int intervalHour,intervalMinute,intervalSecond;//声明间隔时间（响铃周期）
17     Calendar calendar;//声明日历
18     TextView time_tv,time_tv2;
19 
20     @Override
21     protected void onCreate(Bundle savedInstanceState) {
22         super.onCreate(savedInstanceState);
23         setContentView(R.layout.activity_main);
24         alarmManagerSet= (AlarmManager) getSystemService(ALARM_SERVICE);
25         //设置声明时间格式
26         calendar = Calendar.getInstance();
27         myHour=calendar.get(Calendar.HOUR_OF_DAY);
28         myMinute=calendar.get(Calendar.MINUTE);
29         intervalHour=calendar.get(Calendar.HOUR_OF_DAY);
30         intervalMinute=calendar.get(Calendar.MINUTE);
31         //获取时间设置的TextView
32         time_tv= (TextView) findViewById(R.id.time_tv);
33         time_tv2= (TextView) findViewById(R.id.time_tv2);
34     }
35     //使用timePickerDialog设置闹铃响铃时间
36     public void setTime(View view){
37         TimePickerDialog timePickerDialog =new TimePickerDialog(MainActivity.this, new TimePickerDialog.OnTimeSetListener() {
38             @Override
39             public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
40                 myHour=hourOfDay;
41                 myMinute=minute;
42                 time_tv.setText(myHour+":"+myMinute);
43             }
44         },myHour,myMinute,true);
45         timePickerDialog.show();
46     }
47     //使用timePickerDialog设置闹铃响铃周期（间隔）
48     public void setIntervalTime(View view){
49         TimePickerDialog timePickerDialog =new TimePickerDialog(MainActivity.this, new TimePickerDialog.OnTimeSetListener() {
50             @Override
51             public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
52                 intervalHour=hourOfDay;
53                 intervalMinute=minute;
54                 time_tv2.setText(intervalHour+":"+intervalMinute);
55             }
56         },intervalHour,intervalMinute,true);
57         timePickerDialog.show();
58     }
59     public void open(View view){
60         //分别获取闹铃响铃时间以及闹铃间隔时间（用冒号分割存储于数组中）
61         String[] triggerTime=time_tv.getText().toString().split(":"); 
62         String[] intervalTime=time_tv2.getText().toString().split(":");
63         //通过Calendar分别获取对应的小时和分钟（需要将String转换为int）
64         Calendar calendar1 = Calendar.getInstance();
65         calendar1.set(Calendar.HOUR_OF_DAY,Integer.parseInt(triggerTime[0]));
66         calendar1.set(Calendar.MINUTE,Integer.parseInt(triggerTime[1]));
67         //得到点击触发的毫秒值（即闹钟提醒时间）
68         long triggerAtMillis= calendar1.getTimeInMillis();
69         //设定pendinngIntent接受自定义闹铃广播
70         pendingIntentSet = PendingIntent.getBroadcast(this,0,new Intent("repeatAlarm"),0);
71         //判断如果当前系统时间大于设置的闹铃时间，则在第二天开始启用该闹铃
72         if(System.currentTimeMillis()>triggerAtMillis){
73             triggerAtMillis=triggerAtMillis+24*60*60*1000;
74         }
75         //使用.setRepeating设置重复闹铃
76         alarmManagerSet.setRepeating(AlarmManager.RTC_WAKEUP,triggerAtMillis,intervalMillis,pendingIntentSet);
77     }
78     public void stop(View v){
79         alarmManagerSet.cancel(pendingIntentSet);
80     }
81 }