标签：this 传递 androi blog 发送广播 rmi else null orm
广播分类:
标准广播（Normal broadcasts）：完全异步执行的广播，接收没有先后顺序，效率高，无法被接收器被拦截。
有序广播(Ordered broadcasts) ：同步执行的广播，有先后顺序，广播可以被接收器拦截或修改。
接收系统广播：
动态注册监听网络变化：（只能在程序启动后才能接收到广播，程序结束，广播取消）
1.再activity中注册广播并处理接收后的逻辑
public class MainActivity extends AppCompatActivity { private IntentFilter intentFilter; private NetworkChangeReceiver networkChangeReceiver; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); intentFilter = new IntentFilter(); //添加要接收的广播类型 intentFilter.addAction("android.net.com.CONNECTIVITY_CHANGE"); //创建广播接收者 networkChangeReceiver = new NetworkChangeReceiver(); //注册广播接收者 registerReceiver(networkChangeReceiver,intentFilter); } @Override protected void onDestroy() { super.onDestroy(); //取消注册 unregisterReceiver(networkChangeReceiver); } //自定义广播接收者 class NetworkChangeReceiver extends BroadcastReceiver{ @Override public void onReceive(Context context, Intent intent) { //收到广播后处理相关逻辑 ConnectivityManager connectivityManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE); NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo(); if(networkInfo != null && networkInfo.isAvailable()){ Toast.makeText(context,"network is available",Toast.LENGTH_SHORT).show(); }else { Toast.makeText(context,"network is unavailable",Toast.LENGTH_SHORT).show(); } } } }
2.还要添加访问网络状态的权限：
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
静态注册实现开机启动：（程序结束后还能正常接收广播）
1.创建广播接收类：
public class BootCompleteReceiver extends BroadcastReceiver { public BootCompleteReceiver() { } @Override public void onReceive(Context context, Intent intent) { } }
2.在Manifest中静态注册：
<receiver android:name=".BootCompleteReceiver" android:enabled="true" android:exported="true"> <intent-filter> <action android:name="android.intent.action.BOOT_COMPLETED"/> </intent-filter> </receiver> enable:是否启用广播接收器 exported:是否允许接收器接收本程序以外的广播 添加监听启动完成广播权限： <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>
发送自定义广播:
发送标准广播：
1.首先定义广播接收器
public class MyBroadcastReceiver extends BroadcastReceiver { @Override public void onReceive(Context context, Intent intent) { } }
2.在Manifest中注册：
<receiver android:name=".MyBroadcastReceiver" android:enabled="true" android:exported="true"> <intent-filter> <action android:name="com.example.broadcast.MY_BROADCAST"/> </intent-filter> </receiver>
3.发送广播：
public void onClick(View v) { if(v.getId() == R.id.send){ Intent intent = new Intent("com.example.broadcast.MY_BROADCAST"); sendBroadcast(intent); } }
发送有序广播：
1.在注册广播接收器时给intent-filter设置优先级属性，数值越大，优先级越高
<receiver android:name=".BootCompleteReceiver" android:enabled="true" android:exported="true"> <intent-filter android:priority="100"> <action android:name="android.intent.action.BOOT_COMPLETED"/> </intent-filter> </receiver>
2.发送有序广播：
Intent intent = new Intent("com.example.broadcast.MY_BROADCAST"); sendOrderedBroadcast(intent,null);//只需要修改发送方法
3.接收到广播时进行拦截或者修改处理：
public class BootCompleteReceiver extends BroadcastReceiver { public BootCompleteReceiver() { } @Override public void onReceive(Context context, Intent intent) { abortBroadcast();//拦截广播 setResult(int code,Stirng data, Bundle extras);//修改结果传递给下一个广播 //获取上一个广播传来的数据 getResultCode(); getResultData(); getResultExtras(boolean makeMap); } }
4.终结广播（不管是否拦截，都会最终执行）
Intent intent = new Intent("com.example.broadcast.MY_BROADCAST");
sendOrderedBroadcast(intent,null,new BootCompleteReceiver(),new Handler(),0,null,null);
使用本地广播：
本地广播只能在应用内部传递
1.创建广播接收器
class NetworkChangeReceiver extends BroadcastReceiver{ @Override public void onReceive(Context context, Intent intent) { } } }
2.获取本地广播管理类：
LocalBroadcastManager localBroadcastManager = LocalBroadcastManager.getInstance(this);
3.注册广播接收器
localBroadcastManager.registerReceiver(networkChangeReceiver,intentFilter);
4.发送广播：
localBroadcastManager.sendBroadcast(intent);
5.注销广播
localBroadcastManager.unregisterReceiver(networkChangeReceiver);
标签：this 传递 androi blog 发送广播 rmi else null orm
原文地址：http://www.cnblogs.com/chao-lc/p/6441345.html
