在Android中，Broadcast是一种广泛运用的在应用程序之间传输信息的机制。而BroadcastReceiver是对发送出来的 Broadcast进行过滤接受并响应的一类组件。
目录导航：
- 广播Broadcast的简要说明
- 广播Broadcast的准备工作
- Broadcast广播的测试
- 友情链接
广播Broadcast的简要说明
一、 广播的种类：标准广播和有序广播
- 标准广播：是一种完全异步执行的广播，在广播发出之后，所有的广播接收器几乎都会在同一时刻接收到这条广播消息，因此它们之间没有任何先后顺序可言。这种广播的效率会比较高，但同时也意味着它是无法被截断的
- 有序广播：则是一种同步执行的广播，在广播发出之后，同一时刻只会有一个广播接收器能够收到这条广播消息，当这个广播接收器中的逻辑执行完毕后，广播才会继续传递
二、 注册BroadcastReceiver的两种方式:
- 静态注册：在AndroidManifest.xml中用标签生命注册，并在标签内用标签设置过滤器
<receiver android:name=".NetworkChangeReceiver">
<intent-filter>
<action android:name="com.example.linux.broadcasttest.MyBroadcast" />
</intent-filter>
</receiver>
- 动态注册：在java代码中调用registerReceiver(BroadcastReceiver receiver, IntentFilter filter)方法
Intent intent = new Intent();
intent.putExtra("username", "linux");
intent.setAction("com.example.linux.broadcasttest.MyBroadcast");
sendBroadcast(intent);
广播Broadcast的准备工作
我们建立一个android项目，结构如下：
一、 在MainActivity中初始化一些信息：
private final static String TAG = "OtherReceiver";
private IntentFilter intentFilter;
private NetworkChangeReceiver networkChangeReceiver;
private LocalBroadcastManager localBroadcastManager;
private LocalReceiver localReceiver;
@Override
protected void onCreate(Bundle savedInstanceState) {
Log.i(TAG, "main on create");
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
二、 创建三个广播接收器，用于广播的测试：它们分别如下
- LocalReceiver本地广播：
package com.example.linux.broadcasttest;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.util.Log;
/**
* Created by Linux on 2016/3/7.
*/
public class LocalReceiver extends BroadcastReceiver {
private final static String TAG = "OtherReceiver";
public LocalReceiver() {
Log.i(TAG, "local receiver constructor.");
}
@Override
public void onReceive(Context context, Intent intent) {
String username = intent.getStringExtra("username");
Log.i(TAG, "local username: " + username);
}
}
- OtherReceiver用于测试有序广播：
package com.example.linux.broadcasttest;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.util.Log;
public class OtherReceiver extends BroadcastReceiver {
private final static String TAG = "OtherReceiver";
public OtherReceiver() {
Log.i(TAG, "other receiver constructor.");
}
@Override
public void onReceive(Context context, Intent intent) {
String username = intent.getStringExtra("username");
Log.i(TAG, "other username: " + username);
abortBroadcast();
}
}
- NetworkChangeReceiver用于测试系统广播的使用：
package com.example.linux.broadcasttest;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.util.Log;
/**
* Created by Linux on 2016/3/7.
*/
public class NetworkChangeReceiver extends BroadcastReceiver {
private final static String TAG = "OtherReceiver";
public NetworkChangeReceiver() {
Log.i(TAG, "network receiver constructor.");
}
@Override
//Intent是sendBroadcast中的参数
public void onReceive(Context context, Intent intent) {
String username = intent.getStringExtra("username");
Log.i(TAG, "network username: " + username);
}
}
三、 由于广播会涉及到注册，这里我把广播的注册代码贴出来：在AndroidManifest.xml文件中
<receiver android:name=".NetworkChangeReceiver">
<intent-filter>
<action android:name="com.example.linux.broadcasttest.MyBroadcast" />
</intent-filter>
</receiver>
<receiver android:name=".OtherReceiver">
<intent-filter android:priority="100">
<action android:name="com.example.linux.broadcasttest.MyBroadcast" />
</intent-filter>
</receiver>
<receiver android:name=".LocalReceiver">
<intent-filter>
<action android:name="com.example.linux.broadcasttest.MyBroadcast" />
</intent-filter>
</receiver>
Broadcast广播的测试
一、 定义方法sendSystemBroad，用于发送系统广播
// 发送系统广播
public void sendSystemBroad(View view) {
intentFilter = new IntentFilter();
intentFilter.addAction("android.net.conn.CONNECTIVITY_CHANGE");
networkChangeReceiver = new NetworkChangeReceiver();
registerReceiver(networkChangeReceiver, intentFilter);
}
- 打印的结果：
03-23 23:03:20.087 31259-31259/com.example.linux.broadcasttest I/OtherReceiver: other receiver constructor. 03-23 23:03:20.087 31259-31259/com.example.linux.broadcasttest I/OtherReceiver: other username: linux 03-23 23:03:20.097 31259-31259/com.example.linux.broadcasttest I/OtherReceiver: network receiver constructor. 03-23 23:03:20.107 31259-31259/com.example.linux.broadcasttest I/OtherReceiver: network username: linux 03-23 23:03:20.107 31259-31259/com.example.linux.broadcasttest I/OtherReceiver: local receiver constructor. 03-23 23:03:20.107 31259-31259/com.example.linux.broadcasttest I/OtherReceiver: local username: linux
二、 定义方法sendBroadCast，用于测试发送标准广播
// 发送标准广播
public void sendBroadCast(View view) {
Intent intent = new Intent();
intent.putExtra("username", "linux");
intent.setAction("com.example.linux.broadcasttest.MyBroadcast");
sendBroadcast(intent);
}
- 打印的结果：
03-23 23:05:47.957 31259-31259/com.example.linux.broadcasttest I/OtherReceiver: network receiver constructor. 03-23 23:05:47.967 31259-31259/com.example.linux.broadcasttest I/OtherReceiver: network username: null
三、 定义方法sendOrderBroad，用于测试有序广播
// 发送有序广播
public void sendOrderBroad(View view) {
Intent intent = new Intent();
intent.putExtra("username", "linux");
intent.setAction("com.example.linux.broadcasttest.MyBroadcast");
sendOrderedBroadcast(intent, null);
}
- 打印的结果：
03-23 23:07:28.877 31259-31259/com.example.linux.broadcasttest I/OtherReceiver: other receiver constructor. 03-23 23:07:28.877 31259-31259/com.example.linux.broadcasttest I/OtherReceiver: other username: linux
四、 定义方法sendLocalBroad，用于测试本地广播
// 使用本地广播
public void sendLocalBroad(View view) {
localBroadcastManager = LocalBroadcastManager.getInstance(this);
Intent intent = new Intent();
intent.putExtra("username", "linux");
intent.setAction("com.example.linux.broadcasttest.MyBroadcast");
localBroadcastManager.sendBroadcast(intent);
}
- 打印的结果：
03-23 23:28:09.327 31259-31259/com.example.linux.broadcasttest I/OtherReceiver: local username: linux 03-23 23:28:09.327 31259-31259/com.example.linux.broadcasttest I/OtherReceiver: local username: linux 03-23 23:28:09.327 31259-31259/com.example.linux.broadcasttest I/OtherReceiver: local username: linux
友情链接
- 广播的测试源代码 访问密码 1e16
时间： 2024-10-07 02:10:38