android中如何发送一个广播

1.首先要声明广播

private BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver()
{
    @Override
    public void onReceive(Context context, Intent intent) //onReceive函数不能做耗时的事情，参考值：10s以内
    {
        Log.d("scott", "on receive action="+intent.getAction());
        String action = intent.getAction();
        if (action.equals("com.scott.sayhi"))
        {
            showDialog("on receive action="+intent.getAction());
        }
    }
};

2.其次要注册广播，有两种方式：xml注册和代码注册

 

xml注册：

<receiver Android:name="com.scott.sayhi.MyBroadcastReceiver" >
<intent-filter>
<action android:name="com.scott.sayhi" />
</intent-filter>
</receiver>

代码注册：

IntentFilter filter = new IntentFilter();
filter.addAction("com.scott.sayhi");
MyActivity.this.registerReceiver(mBroadcastReceiver, filter);

上述2个步骤就可以了。

3.发送广播

Intent intent = new Intent();
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.setAction("com.scott.sayhi");
MyActivity.this.sendBroadcast(intent);

4.收听开机广播

intent-filter设置如下即可

<intent-filter>
<action android:name="android.intent.action.BOOT_COMPLETED" />
<category android:name="android.intent.category.HOME" />
</intent-filter>