简单实现Android闹钟程序 附源码

这个应用实现了简单的闹钟功能，关闭程序的状态中也可以进行闹钟的提醒。
这里遗留了一个问题：
如果我通过应用本身关闭程序，是可以实现我上述所说的功能，但是如果我在手机进程管理中实现应用程序的关闭操作，这个提醒就不起作用了，我很疑惑的是，我通过应用程序本身关闭了后，在进程中也是查看不到这个应用了的。所以哪位知道的帮留个言指点下，谢谢。
clockdemo.java

package com.example.clock;

import java.util.calendar;
import android.app.activity;
import android.app.alertdialog;
import android.app.timepickerdialog;
import android.content.dialoginterface;
import android.os.bundle;
import android.view.keyevent;
import android.view.view;
import android.widget.button;
import android.widget.timepicker;

public class clockdemo extends activity {

 private button mset;
 calendar mcalendar = calendar.getinstance();

 /** called when the activity is first created. */
 @override
 public void oncreate(bundle savedinstancestate) {
 super.oncreate(savedinstancestate);
 setcontentview(r.layout.main);
 objectpool.malarmhelper = new alarmhelper(this);
 mset = (button) findviewbyid(r.id.mset);
 setlistener();
 }

 public void setlistener() {
 mset.setonclicklistener(new view.onclicklistener() {
  public void onclick(view v) {
  mcalendar.settimeinmillis(system.currenttimemillis());
  int mhour = mcalendar.get(calendar.hour_of_day);
  int mminute = mcalendar.get(calendar.minute);
  new timepickerdialog(clockdemo.this,
   new timepickerdialog.ontimesetlistener() {
    public void ontimeset(timepicker view,
     int hourofday, int minute) {
    mcalendar.settimeinmillis(system
     .currenttimemillis());
    mcalendar.set(calendar.hour_of_day, hourofday);
    mcalendar.set(calendar.minute, minute);
    mcalendar.set(calendar.second, 0);
    mcalendar.set(calendar.millisecond, 0);
    objectpool.malarmhelper.openalarm(32, "ddd",
     "ffff", mcalendar.gettimeinmillis());
    }
   }, mhour, mminute, true).show();
  }
 });
 }

 @override
 public boolean onkeydown(int keycode, keyevent event) {
 if (keycode == keyevent.keycode_back) {
  showbackdialog();
  return true;
 }
 return super.onkeydown(keycode, event);
 }

 /** give the tip when exit the application. */
 public void showbackdialog() {
 final alertdialog.builder builder = new alertdialog.builder(this);
 builder.settitle("提示")
  .seticon(r.drawable.icon)
  .setmessage("是否退出?")
  .setpositivebutton("sure",
   new dialoginterface.onclicklistener() {
    public void onclick(dialoginterface dialog,
     int which) {
    system.exit(0);
    android.os.process
     .killprocess(android.os.process.mypid());

    dialog.dismiss();
    }
   })
  .setnegativebutton("cancel",
   new dialoginterface.onclicklistener() {
    public void onclick(dialoginterface dialog,
     int which) {
    dialog.dismiss();
    }
   });
 alertdialog ad = builder.create();
 ad.show();
 }

}

alarmhelper.java

package com.example.clock;

import android.app.alarmmanager;
import android.app.pendingintent;
import android.content.context;
import android.content.intent;

public class alarmhelper {

 private context c;
 private alarmmanager malarmmanager;

 public alarmhelper(context c) {
 this.c = c;
 malarmmanager = (alarmmanager) c
  .getsystemservice(context.alarm_service);
 }

 public void openalarm(int id, string title, string content, long time) {
 intent intent = new intent();
 intent.putextra("_id", id);
 intent.putextra("title", title);
 intent.putextra("content", content);
 intent.setclass(c, callalarm.class);
 pendingintent pi = pendingintent.getbroadcast(c, id, intent,
  pendingintent.flag_update_current);
 malarmmanager.set(alarmmanager.rtc_wakeup, time, pi);
 }

 public void closealarm(int id, string title, string content) {
 intent intent = new intent();
 intent.putextra("_id", id);
 intent.putextra("title", title);
 intent.putextra("content", content);
 intent.setclass(c, callalarm.class);
 pendingintent pi = pendingintent.getbroadcast(c, id, intent, 0);
 malarmmanager.cancel(pi);
 }
}

callalarm.java

package com.example.clock;

import android.content.broadcastreceiver;
import android.content.context;
import android.content.intent;

public class callalarm extends broadcastreceiver {
 @override
 public void onreceive(context context, intent intent) {
 intent.setclass(context, alarmalert.class);
 intent.addflags(intent.flag_activity_new_task);
 context.startactivity(intent);
 }
}

alarmalert.java

package com.example.clock;

import android.app.activity;
import android.app.alertdialog;
import android.content.dialoginterface;
import android.os.bundle;

public class alarmalert extends activity {
 @override
 protected void oncreate(bundle savedinstancestate) {
 super.oncreate(savedinstancestate);
 new alertdialog.builder(alarmalert.this)
  .seticon(r.drawable.clock)
  .settitle("ddd")
  .setmessage("fff")
  .setpositivebutton("ddd",
   new dialoginterface.onclicklistener() {
    public void onclick(dialoginterface dialog,
     int whichbutton) {
    system.exit(0);
    android.os.process
     .killprocess(android.os.process.mypid());
    }
   }).show();
 }
}
objectpool.java
public class objectpool {

 /** the alarm object. */
 public static alarmhelper malarmhelper;

}

看了那么多，估计某些人又嫌烦了，我只贴上代码的目的是希望大家能看代码，而不是电脑上下了一个又一个的源文件，只知道用而不关心其中的技术点，这样就不能举一番三了。

源码下载：http://xiazai.jb51.net/201607/yuanma/clockdemo(jb51.net).rar

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。