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);  
    }  
});  

 

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