什麼是定義一個接收器的類別參數

Question

我知道，當我定義一個廣播接收器從清單意圖過濾器時我可以定義類別它是可選的。

<receiver android:name=".PushMessageReceiver" > 
    <intent-filter> 
      <!-- Receives the actual messages. --> 
      <category android:name="com.test.myAppname" /> 
      <action android:name="com.test.client.MSGRECEIVE" /> 
    </intent-filter> 
</receiver> 

我GOOGLE了，但不能得到它的是加入類別或如何我可以用它的確切點。我很欣賞給我一些例子。

Answer 1

MainActivity.java

import android.app.Activity; 
import android.content.Intent; 
import android.os.Bundle; 
import android.view.View; 
import android.view.View.OnClickListener; 
import android.widget.Button; 
/** 
* send 
* 
*/ 
public class MainActivity extends Activity { 
    private static final String MY_ACTION = "com.chaowen.action.MY_ACTION"; 
    private Button btn; 

    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.main); 

     btn = (Button)findViewById(R.id.Button01); 
     btn.setOnClickListener(new OnClickListener() { 

      @Override 
      public void onClick(View v) { 
       Intent intent= new Intent(); 
       intent.setAction(MY_ACTION); 
       //Intent message 
       intent.putExtra("msg", "ha ha"); 
       //send 
       sendBroadcast(intent); 

      } 
     }); 
    } 
} 

MyReceiver.java

import android.content.BroadcastReceiver; 
import android.content.Context; 
import android.content.Intent; 
import android.widget.Toast; 
/** 
* receive  
* 
*/ 
public class MyReceive extends BroadcastReceiver { 

    @Override 
    public void onReceive(Context context, Intent intent) { 
     //get Intent message 
     String msg = intent.getStringExtra("msg"); 
     Toast.makeText(context, msg, Toast.LENGTH_LONG).show(); 
    } 

} 

main.xml中

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    android:orientation="vertical" 
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent" 
    > 
<Button 
    android:text="send..." 
    android:id="@+id/Button01" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    /> 
</LinearLayout> 

的AndroidManifest.xml

<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
    package="com.chaowen" 
    android:versionCode="1" 
    android:versionName="1.0"> 
<uses-sdk android:minSdkVersion="4" /> 

<application android:icon="@drawable/icon" android:label="@string/app_name"> 
    <activity android:name=".MainActivity" 
       android:label="@string/app_name"> 
     <intent-filter> 
      <action android:name="android.intent.action.MAIN" /> 
      <category android:name="android.intent.category.LAUNCHER" /> 
     </intent-filter> 
    </activity> 
     <receiver 
      android:name="MyReceive" 
      > 
      <intent-filter> 
      <action 
       android:name="com.chaowen.action.MY_ACTION" /> 
      </intent-filter> 
      </receiver> 
</application>