学习android的Broadcast,笔记记录于此。
BroadCastRecevier用于接受其他应用发送的广播.
BroadCastReceiver工作,需要2步。
创建Broadcast Recevier.
注册Braodcast Recevier.
参考链接
https://www.tutorialspoint.com/android/android_broadcast_receivers.htm
http://blog.csdn.net/mr_dsw/article/details/51394350
创建BroadcastReceiver
Android stuido创建project, 名称broadcastTest。
继承BroadcastReceiver,用于接收广播。
MyReceiver.java
package com.example.tony.broadcasttest;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.util.Log;
import android.widget.Toast;
public class MyReceiver extends BroadcastReceiver {
// 接受到广播调用
@Override
public void onReceive(Context context, Intent intent) {
// TODO: This method is called when the BroadcastReceiver is receiving
// an Intent broadcast.
// throw new UnsupportedOperationException("Not yet implemented");
Log.i("receive", "onReceive");
Toast.makeText(context, "intent Detected", Toast.LENGTH_LONG).show();
}
}
注册receiver
使用标签注册broadcastReceiver。
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.tony.broadcasttest">
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<!-- 注册Receiver,并定义action
action name自己定义,但是发送广播的时候也要发送相同的广播,Receiver才能接收到 -->
<receiver
android:name=".MyReceiver"
android:enabled="true"
android:exported="true">
<intent-filter>
<action android:name="com.example.CUSTOM_INTENT" />
</intent-filter>
</receiver>
</application>
</manifest>
布局文件
布局文件中定义一个按键用于发送广播
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.tony.broadcasttest.MainActivity">
<Button
android:id="@+id/send_broadcast"
android:text="send broadcast"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</RelativeLayout>
MainActivity
按键按下,通过sendBroadcast()发送自己定义的广播。
MainActivity.java
package com.example.tony.broadcasttest;
import android.content.Intent;
import android.content.IntentFilter;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
public class MainActivity extends AppCompatActivity {
Button sendBroadcast;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
sendBroadcast = (Button) findViewById(R.id.send_broadcast);
// 按键按下,发送广播
sendBroadcast.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
broadcastIntent(v);
}
});
// 手动注册广播,在AndroidManifest.xml中注册了就不需要手动注册
/*
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction("com.example.CUSTOM_INTENT");
registerReceiver(new MyReceiver(), intentFilter);
*/
}
public void broadcastIntent(View view) {
Intent intent = new Intent();
// 发送自己广播,名称自己定义,只要在AndroidManifest.xmL中注册,让Receive接受即可。
intent.setAction("com.example.CUSTOM_INTENT");
sendBroadcast(intent);
Log.i("sendBraodcast", "braodcastintent");
}
}
这个demo只是无序广播的demo。对于有序广播,后面再分析。
Tony Liu
2017-3-3, Shenzhen