前言：

AIDL：Android Interface Definition Language，翻译过来就是Android接口定义语言。是用于定义服务器和客户端通信接口的一种描述语言，可以拿来生成用于IPC的代码。所以使用AIDL需要一个服务端和客户端
作用：可以在一个进程中获取另一个进程的数据和调用其暴露出来的方法，从而满足进程间通信的需求。

1.AIDL支持的基本数据类型

1. 八种基本数据类型：byte、char、short、int、long、float、double、boolean
2. String，CharSequence
3. 实现了Parcelable接口的数据类型
4. List 类型。List承载的数据必须是AIDL支持的类型，或者是其它声明的AIDL对象
5. Map类型。Map承载的数据必须是AIDL支持的类型，或者是其它声明的AIDL对象

2.服务端的实现

   创建工程，以及所需aidl文件

• 使用Android Studio新建一个工程,命名为TestAidlDemo1
• 右键New一个AIDL文件，取名为IAidlInterface，AS会自动在工程目录生成一个路径完全一样的aidl文件夹
• 既然是要回调消息，那就还需要一个回调接口，同样的方法，创建IAidlCallBack.aidl文件，那么接下来就进行代码编写

实现代码逻辑

• 编写IAidlInterface.aldi代码，因为我们需要回调消息，那么我们需要注册回调以及注销回调接口，一个发送消息的接口，一个获取历史消息的接口，代码如下(AIDL文件不会自动导包,一些不是基本支持数据类型需要我们自己手动import，)

   import com.pgc.testaidldemo1.IAidlCallBack; interface IAidlInterface {     /**      * Demonstrates some basic types that you can use as parameters      * and return values in AIDL.      */     void registerCallBack(IAidlCallBack iAidlCallBack);     void unregisterCallBack(IAidlCallBack iAidlCallBack);     void sendMessage(String message);     List<String> getMessages(); } 

   

• 编写IAidlCallBack.aidl代码：既然是回调接口，那么我们只需要一个消息发送成功的回调接口就行，代码如下

   interface IAidlCallBack {     /**      * Demonstrates some basic types that you can use as parameters      * and return values in AIDL.      */     void onMessageSuccess(String message); }

   

• 既然是服务端，我们需要实现接收消息已经处理消息的逻辑代码，所以我们创建一个AidlService，继承Service,因为Service不能直接接收Callback,但是提供了RemoteCallbackList来注册回调

   private RemoteCallbackList<IAidlCallBack> callbackList= new RemoteCallbackList<>();

  同时RemoteCallbackList提供了beginBroadcast来获取当前注册的回调数，因此我们可以通过这个方法进行回调处理(再使用了beginBroadcast之后必须调用finishBroadcast不然会报beginBroadcast() called while already in a broadcast错误)

   final int num=callbackList.beginBroadcast(); for (int i=0;i<num;i++){      IAidlCallBack iAidlCallBack=callbackList.getBroadcastItem(i);      iAidlCallBack.onMessageSuccess(message);     } callbackList.finishBroadcast();

   接下来实例化binder对象并返回给客户端，

   @Override     public IBinder onBind(Intent intent) {         return binder;     }      private final IAidlInterface.Stub binder=new IAidlInterface.Stub() {         @Override         public void registerCallBack(IAidlCallBack iAidlCallBack) throws RemoteException {             callbackList.register(iAidlCallBack);         }          @Override         public void unregisterCallBack(IAidlCallBack iAidlCallBack) throws RemoteException {             callbackList.unregister(iAidlCallBack);         }          @Override         public void sendMessage(String message) throws RemoteException {             messages.add(message);             final int num=callbackList.beginBroadcast();             for (int i=0;i<num;i++){                 IAidlCallBack iAidlCallBack=callbackList.getBroadcastItem(i);                 iAidlCallBack.onMessageSuccess(message);             }             callbackList.finishBroadcast();         }          @Override         public List<String> getMessages() throws RemoteException {             return messages;         }     };

    

• 在AndroidManifest.xml注册Service

   <service android:name=".AidlService"          android:enabled="true"          android:exported="true"             >     <intent-filter android:priority="1000">             <action android:name="AIDL.service"></action>    </intent-filter> </service>

   

• AidlService全部代码

   package com.pgc.testaidldemo1;  import android.annotation.SuppressLint; import android.app.Service; import android.content.Intent; import android.os.IBinder; import android.os.RemoteCallbackList; import android.os.RemoteException;  import androidx.annotation.Nullable;  import java.util.ArrayList; import java.util.List;   /**  * Created by PengGuiChu on 2020/4/11.  */ @SuppressLint("Registered") public class AidlService extends Service {     private RemoteCallbackList<IAidlCallBack> callbackList= new RemoteCallbackList<>();     private List<String> messages=new ArrayList<>();     @Nullable     @Override     public IBinder onBind(Intent intent) {         return binder;     }      private final IAidlInterface.Stub binder=new IAidlInterface.Stub() {         @Override         public void registerCallBack(IAidlCallBack iAidlCallBack) throws RemoteException {             callbackList.register(iAidlCallBack);         }          @Override         public void unregisterCallBack(IAidlCallBack iAidlCallBack) throws RemoteException {             callbackList.unregister(iAidlCallBack);         }          @Override         public void sendMessage(String message) throws RemoteException {             messages.add(message);             final int num=callbackList.beginBroadcast();             for (int i=0;i<num;i++){                 IAidlCallBack iAidlCallBack=callbackList.getBroadcastItem(i);                 iAidlCallBack.onMessageSuccess(message);             }             callbackList.finishBroadcast();         }          @Override         public List<String> getMessages() throws RemoteException {             return messages;         }     };      @Override     public void onCreate() {         super.onCreate();     } } 

   

• 因为是服务端和客户端实现相互消息回调，因此在服务端也需要通过binderService来获取binder，相对客户端，因为服务端和AidlService是在同一线程，我们可以直接binderService

   Intent intent=new Intent(getApplicationContext(),AidlService.class); bindService(intent,serviceConnection,BIND_AUTO_CREATE);

  然后实例化ServiceConnection

   private ServiceConnection serviceConnection=new ServiceConnection() {         @Override         public void onServiceConnected(ComponentName componentName, IBinder iBinder) {                      }          @Override         public void onServiceDisconnected(ComponentName componentName) {          } };

  然后在onServiceConnected中获取binder

   iAidlInterface=IAidlInterface.Stub.asInterface(iBinder); try {       iAidlInterface.asBinder().linkToDeath(mDeathRecipient, 0);//监听进程是否消失       iAidlInterface.registerCallBack(iAidlCallBack);//注册消息回调       messages.addAll(iAidlInterface.getMessages());//获取历史消息       listView.setAdapter(arrayAdapter=new ArrayAdapter<>        (getApplicationContext(),android.R.layout.simple_list_item_1,messages)); } catch (RemoteException e) {        e.printStackTrace(); }

  DeathRecipient实例

       private IBinder.DeathRecipient mDeathRecipient = new IBinder.DeathRecipient() {         //当承载IBinder的进程消失时接收回调的接口         @Override         public void binderDied() {             if (null == iAidlInterface) {                 return;             }             try {                 iAidlInterface.unregisterCallBack(iAidlCallBack);//注销             } catch (RemoteException e) {                 e.printStackTrace();             }             iAidlInterface.asBinder().unlinkToDeath(mDeathRecipient, 0);             iAidlInterface = null;         }     };

  iAidlCallBack实例

       private IAidlCallBack iAidlCallBack=new IAidlCallBack.Stub() {         @Override         public void onMessageSuccess(String message) {             if (messages!=null&&arrayAdapter!=null){                 messages.add(message);                 handler.sendEmptyMessage(1);             }         }     };

   MainActivity全部代码

   package com.pgc.testaidldemo1;    import android.annotation.SuppressLint; import android.content.ComponentName; import android.content.Intent; import android.content.ServiceConnection; import android.os.Bundle; import android.os.Handler; import android.os.IBinder; import android.os.Message; import android.os.RemoteException; import android.view.View; import android.widget.ArrayAdapter; import android.widget.ListView;  import androidx.annotation.NonNull; import androidx.appcompat.app.AppCompatActivity; import java.util.ArrayList; import java.util.List;  import butterknife.BindView; import butterknife.ButterKnife; import butterknife.OnClick;  public class MainActivity extends AppCompatActivity {     @BindView(R.id.list_view)     ListView listView;     private IAidlInterface iAidlInterface;     private int num;     private List<String> messages=new ArrayList<>();     private ArrayAdapter arrayAdapter;     @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);         ButterKnife.bind(this);         Intent intent=new Intent(getApplicationContext(),AidlService.class);         bindService(intent,serviceConnection,BIND_AUTO_CREATE);     }       @OnClick(R.id.send_message)     public void onViewClicked(View view) {         if (iAidlInterface!=null){             try {                 iAidlInterface.sendMessage("消息"+num);                 num++;             } catch (RemoteException e) {                 e.printStackTrace();             }         }     }      private ServiceConnection serviceConnection=new ServiceConnection() {         @Override         public void onServiceConnected(ComponentName componentName, IBinder iBinder) {             iAidlInterface=IAidlInterface.Stub.asInterface(iBinder);             try {                 iAidlInterface.asBinder().linkToDeath(mDeathRecipient, 0);//监听进程是否消失                 iAidlInterface.registerCallBack(iAidlCallBack);//注册消息回调                 messages.addAll(iAidlInterface.getMessages());//获取历史消息                 listView.setAdapter(arrayAdapter=new ArrayAdapter<>(getApplicationContext(),android.R.layout.simple_list_item_1,messages));             } catch (RemoteException e) {                 e.printStackTrace();             }         }          @Override         public void onServiceDisconnected(ComponentName componentName) {          }     };      private IBinder.DeathRecipient mDeathRecipient = new IBinder.DeathRecipient() {         //当承载IBinder的进程消失时接收回调的接口         @Override         public void binderDied() {             if (null == iAidlInterface) {                 return;             }             try {                 iAidlInterface.unregisterCallBack(iAidlCallBack);//注销             } catch (RemoteException e) {                 e.printStackTrace();             }             iAidlInterface.asBinder().unlinkToDeath(mDeathRecipient, 0);             iAidlInterface = null;         }     };      private IAidlCallBack iAidlCallBack=new IAidlCallBack.Stub() {         @Override         public void onMessageSuccess(String message) {             if (messages!=null&&arrayAdapter!=null){                 messages.add(message);                 handler.sendEmptyMessage(1);             }         }     };      @SuppressLint("HandlerLeak")     private Handler handler=new Handler(){         @Override         public void handleMessage(@NonNull Message msg) {             arrayAdapter.notifyDataSetChanged();         }     };      @Override     protected void onDestroy() {         //解除注册         if (null != iAidlInterface && iAidlInterface.asBinder().isBinderAlive()) {             try {                 iAidlInterface.unregisterCallBack(iAidlCallBack);             } catch (RemoteException e) {                 e.printStackTrace();             }         }         //解除绑定服务         unbindService(serviceConnection);         super.onDestroy();     } } 

  到此我们的服务端就编码完成，实现效果

3.客户端实现

   创建client工程

•      选中TestAidlDemo1工程右键NEW一个model，命名为client
• 要想client项目能够连接上Service，我们直接复制上面工程的aidl文件到client工程的main文件里，这样是为了保证两个项目的aidl文件路径一致

• 而调用逻辑基本和上面MainActivity一样，需要注意一点的是，因为是两个不同进程，在这里我们不能直接bindService来调起服务端，而是通过以下代码实现

   Intent intent=new Intent(); String ACTION = "AIDL.service";//对应服务端AndroidManifest.xml配置service action:name intent.setAction(ACTION); intent.setPackage("com.pgc.testaidldemo1");//对应服务端AndroidManifest.xml package bindService(intent,serviceConnection,BIND_AUTO_CREATE);

   

• client的MainActivity全部代码

   package com.pgc.client;  import android.annotation.SuppressLint; import android.content.ComponentName; import android.content.Intent; import android.content.ServiceConnection; import android.os.Bundle; import android.os.Handler; import android.os.IBinder; import android.os.Message; import android.os.RemoteException; import android.view.View; import android.widget.ArrayAdapter; import android.widget.ListView;  import androidx.annotation.NonNull; import androidx.appcompat.app.AppCompatActivity;  import com.pgc.testaidldemo1.IAidlCallBack; import com.pgc.testaidldemo1.IAidlInterface;  import java.util.ArrayList; import java.util.List;  import butterknife.BindView; import butterknife.ButterKnife; import butterknife.OnClick;  public class MainActivity extends AppCompatActivity {     @BindView(R.id.list_view)     ListView listView;     private IAidlInterface iAidlInterface;     private int num;     private List<String> messages=new ArrayList<>();     private ArrayAdapter arrayAdapter;     @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);         ButterKnife.bind(this);         Intent intent=new Intent();         String ACTION = "AIDL.service";         intent.setAction(ACTION);         intent.setPackage("com.pgc.testaidldemo1");         bindService(intent,serviceConnection,BIND_AUTO_CREATE);     }       @OnClick(R.id.send_message)     public void onViewClicked(View view) {         if (iAidlInterface!=null){             try {                 iAidlInterface.sendMessage("消息"+num);                 num++;             } catch (RemoteException e) {                 e.printStackTrace();             }         }     }      private ServiceConnection serviceConnection=new ServiceConnection() {         @Override         public void onServiceConnected(ComponentName componentName, IBinder iBinder) {             iAidlInterface=IAidlInterface.Stub.asInterface(iBinder);             try {                 iAidlInterface.asBinder().linkToDeath(mDeathRecipient, 0);                 iAidlInterface.registerCallBack(iAidlCallBack);                 messages.addAll(iAidlInterface.getMessages());                 listView.setAdapter(arrayAdapter=new ArrayAdapter<>(getApplicationContext(),android.R.layout.simple_list_item_1,messages));             } catch (RemoteException e) {                 e.printStackTrace();             }         }          @Override         public void onServiceDisconnected(ComponentName componentName) {          }     };      private IBinder.DeathRecipient mDeathRecipient = new IBinder.DeathRecipient() {         //当承载IBinder的进程消失时接收回调的接口         @Override         public void binderDied() {             if (null == iAidlInterface) {                 return;             }             iAidlInterface.asBinder().unlinkToDeath(mDeathRecipient, 0);             iAidlInterface = null;             //断线重来逻辑         }     };      private IAidlCallBack iAidlCallBack=new IAidlCallBack.Stub() {         @Override         public void onMessageSuccess(String message) {             if (messages!=null&&arrayAdapter!=null){                 messages.add(message);                 handler.sendEmptyMessage(1);             }         }     };      @SuppressLint("HandlerLeak")     private Handler handler=new Handler(){         @Override         public void handleMessage(@NonNull Message msg) {             arrayAdapter.notifyDataSetChanged();         }     };      @Override     protected void onDestroy() {         //解除注册         if (null != iAidlInterface && iAidlInterface.asBinder().isBinderAlive()) {             try {                 iAidlInterface.unregisterCallBack(iAidlCallBack);             } catch (RemoteException e) {                 e.printStackTrace();             }         }         //解除绑定服务         unbindService(serviceConnection);         super.onDestroy();     } } 

   

• 运行效果

• 

源码下载地址

https://github.com/pengkongkong/TestAidlDemo1