AIDL sample

AIDL

1.编写一个AIDL

如：

package com.elfylin; interface IMyService {     String getValue();}

AIDL和java一样，要保证路径和包名一样。

不过不是每一个java对象，AIDL都支持，不需要声明的有int、boolean、String、CharSequence，在List、Map、Parcelabels也只能包含基本类型。

2.，通过ADT生成一个java文件。

如下：

package com.elfylin;public interface IMyService extends android.os.IInterface{/** Local-side IPC implementation stub class. */    public static abstract class Stub extends android.os.Binder implements com.elfylin.IMyService    {        private static final java.lang.String DESCRIPTOR = "com.elfylin.IMyService";        /** Construct the stub at attach it to the interface. */        public Stub()        {            this.attachInterface(this, DESCRIPTOR);        }        /**         * Cast an IBinder object into an com.elfylin.IMyService interface,         * generating a proxy if needed.         */        public static com.elfylin.IMyService asInterface(android.os.IBinder obj)        {            if ((obj==null)) {                return null;            }            android.os.IInterface iin = (android.os.IInterface)obj.queryLocalInterface(DESCRIPTOR);            if (((iin!=null)&&(iin instanceof com.elfylin.IMyService))) {                return ((com.elfylin.IMyService)iin);            }            return new com.elfylin.IMyService.Stub.Proxy(obj);        }        public android.os.IBinder asBinder()        {            return this;        }        @Override public boolean onTransact(int code, android.os.Parcel data, android.os.Parcel reply, int flags) throws android.os.RemoteException        {            switch (code)            {                case INTERFACE_TRANSACTION:                {                    reply.writeString(DESCRIPTOR);                    return true;                }                case TRANSACTION_getValue:                {                    data.enforceInterface(DESCRIPTOR);                    java.lang.String _result = this.getValue();                    reply.writeNoException();                    reply.writeString(_result);                    return true;                }            }            return super.onTransact(code, data, reply, flags);        }        private static class Proxy implements com.elfylin.IMyService        {            private android.os.IBinder mRemote;            Proxy(android.os.IBinder remote)            {                mRemote = remote;            }            public android.os.IBinder asBinder()            {                return mRemote;            }            public java.lang.String getInterfaceDescriptor()            {                return DESCRIPTOR;            }            public java.lang.String getValue() throws android.os.RemoteException            {                android.os.Parcel _data = android.os.Parcel.obtain();                android.os.Parcel _reply = android.os.Parcel.obtain();                java.lang.String _result;                try {                    _data.writeInterfaceToken(DESCRIPTOR);                    mRemote.transact(Stub.TRANSACTION_getValue, _data, _reply, 0);                    _reply.readException();                    _result = _reply.readString();                }                finally {                    _reply.recycle();                    _data.recycle();                }                return _result;            }        }        static final int TRANSACTION_getValue = (android.os.IBinder.FIRST_CALL_TRANSACTION + 0);    }    public java.lang.String getValue() throws android.os.RemoteException;}

里面有如下信息

a. IMyService继承IInterface，因此有asBinder这个函数

b 里面的内部类Stub

Stub继承了Binder，实现了IMyService。

实现了IInterface的asBinder()，实现了IMyService的getValue（）函数。

增加了com.elfylin.IMyService asInterface(android.os.IBinder obj)

重载了Binder的 onTransact(int code, android.os.Parcel data, android.os.Parcel reply, int flags)

c 内部类 Proxy

Proxy实现了com.elfylin.IMyService

里面有一个内部变量private android.os.IBinder mRemote;

增加了android.os.IBinder asBinder()

java.lang.String getInterfaceDescriptor()

实现了getValue()

3.Service实现

a 编写一个Service的Android工程作为外壳。类名MyService继承Service。

b 在里面些一个自己的类MyServiceImpl继承IMyService.Stub

重写里面的getValue，变成自己的实现。

c 重写这个Service外壳的onBinder函数，返回继承于IMyService.Stub MyServiceImpl的实例。

package com.elfylin;import android.app.Service; import android.content.Intent; import android.os.IBinder; import android.os.RemoteException;public class MyService extends Service {     public class MyServiceImpl extends IMyService.Stub {         @Override         public String getValue() throws RemoteException {         return "'test";         }     }     @Override     public IBinder onBind(Intent intent) {     return new MyServiceImpl();     }}

4、客户端实现

a 要把服务器端的AIDL和生成的java文件一起拷贝到客户端的src目录

b 写一个ServiceConnection的回调实例，重载其

public void onServiceConnected(ComponentName name, IBinder service)

public void onServiceDisconnected(ComponentName name)

这两个回调函数

并且在public void onServiceConnected(ComponentName name, IBinder service)中

IMyService myService = IMyService.Stub.asInterface(service)

以此来获取AIDL中的proxy对象

private ServiceConnection serviceConnection = new ServiceConnection() {     @Override     public void onServiceConnected(ComponentName name, IBinder service) {         myService = IMyService.Stub.asInterface(service);         btnInvokeAIDLService.setEnabled(true);     }     @Override         public void onServiceDisconnected(ComponentName name) {     } }; 

c 在onCreate或者其他事件触发中，连接远程服务，并且传入刚才的回调

bindService(new Intent("com.elfy.aidl.IMyService"), serviceConnection

d 在所有需要服务的地方通过myService来调用即可

bindService(new Intent("net.blogjava.mobile.aidl.IMyService"), serviceConnection, Context.BIND_AUTO_CREATE); 

call process：

client:bindService(new Intent,serviceConnection).

service:IBinder onBinder(Intent intent)

    return MyServiceImpl

    call ServiceConnection onServiceConnected(MyServiceImpl);

client: 

    onServiceConnected(service)

    myService = IMyservice.Stub.asInterface(service)

    IMyservice.Stub.asInterface

        return new com.elfylin.IMyService.Stub.Proxy(obj)

    myService = com.elfylin.IMyService.Stub.Proxy

    myService.getValue

    com.elfylin.IMyService.Stub.Proxy.getValue

    mRemote.transact(Stub.TRANSACTION_getValue, _data, _reply, 0);

    service.transact(Stub.TRANSACTION_getValue, _data, _reply, 0)

server

    MyServiceImpl.onTransact

    IMyService.Stub.onTransact

    IMyService.Stub.getValue

    MyServiceImpl.getValue

    reply.writeString(_result);

client

    _result = _reply.readString();