Android广播学习笔记

1、首先我们要在Manifest.xml文件中配置一个<receiver/>标签，这个标签必须有一个android:name属性，值为继承自BroadcastReceiver类的接收器类，并复写onReceiver方法，在该方法中处理接收到广播后需要处理的事情！
2、<receiver/>标签还有一个子标签为<intent-filter/>,这个标签很重要，是指定接收器需要接收哪种广播

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添加的监听器配置文件内容
MyBroadCast是继承了BroadcastReceiver的类

<receiver android:name="MyBroadCast"><intent-filter><action android:name="hb.com.BroadCastDemo.MYBROADCAST"/></intent-filter></receiver>

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给按钮添加绑定的事件，发送广播的过程

btn.setOnClickListener(new Button.OnClickListener(){@Overridepublic void onClick(View v) {System.out.println("onClick");Intent intent = new Intent();intent.setAction(MYBROADCAST);sendBroadcast(intent);}});

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接收广播处理的过程

public class MyBroadCast extends BroadcastReceiver {@Overridepublic void onReceive(Context context, Intent intent) {System.out.println("onReceive");}}

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备注：在AndroidManifest.xml文件中注册，无论应用程序是否处于开启或关闭状态，它任然会是监听状态，这种方式不是很合理
在应用程序的代码中进行注册，registerReceiver()和unregisterReceiver()两个方法

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Notification和NotificationManager的使用

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通过他们可以显示广播信息的内容、图标以及振动等信息

显示效果：类似于收到短信的提示信息

public class BroadCastDemo extends Activity {Notification nf;NotificationManager nm;private static final String MYBROADCAST = "hb.com.BroadCastDemo.MYBROADCAST";private static final int MYID = 1;    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);//得到NotificationManager对象        String service = this.NOTIFICATION_SERVICE;        nm = (NotificationManager)this.getSystemService(service);               //实例化Notification        nf = new Notification();        nf.icon = R.drawable.icon;        nf.tickerText = "notification test";        nf.when = System.currentTimeMillis();                findViewById(R.id.broadCastBtn).setOnClickListener(new Button.OnClickListener(){@Overridepublic void onClick(View v) {Intent intent = new Intent();//发送自定义的广播类型intent.setAction(MYBROADCAST);PendingIntent pi = PendingIntent.getBroadcast(BroadCastDemo.this, 0, intent, 0);nf.setLatestEventInfo(BroadCastDemo.this, "my title", "my content", pi);nm.notify(MYID, nf);}        });                findViewById(R.id.cancelCastBtn).setOnClickListener(new Button.OnClickListener(){@Overridepublic void onClick(View v) {//取消广播nm.cancel(MYID);}        });    }}

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AlarmManager的使用
AlarmManager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

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findViewById(R.id.alarmManagerOpen).setOnClickListener(new Button.OnClickListener(){@Overridepublic void onClick(View v) {Intent intent = new Intent();intent.setAction(MYBROADCAST);PendingIntent pi = PendingIntent.getBroadcast(BroadCastDemo.this, 0, intent, 0);long time = System.currentTimeMillis();AlarmManager am = (AlarmManager)getSystemService(ALARM_SERVICE);am.setRepeating(AlarmManager.RTC_WAKEUP, time, 8 * 1000, pi);}});

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