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

 

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>

 

给按钮添加绑定的事件，发送广播的过程

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

 

接收广播处理的过程

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

 

 

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

 

Notification和NotificationManager的使用

 

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(){
			@Override
			public 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(){
			@Override
			public void onClick(View v) {
				//取消广播
				nm.cancel(MYID);
			}
        });
    }
}

 

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

 

findViewById(R.id.alarmManagerOpen).setOnClickListener(new Button.OnClickListener(){
	@Override
	public 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);
	}
});