AIDL的使用

https://developer.android.google.cn/guide/components/aidl.html

后者是AIDL的说明和使用。

什么情况使用AIDL类型的service？

https://developer.android.google.cn/guide/components/aidl.html中有使用建议，只有允许不同应用的client需要IPC访问service，并且想要在service中处理多线程时，才有必要使用AIDL。

 

如何定义及使用AIDL？

1.     创建 .aidl文件

比如，定义IRemoteService.aidl，在文件中定义接口。

//IRemoteService.aidl
package com.ali.yunos.androiddemo_n.services;

// Declare any non-default types here withimport statements

interface IRemoteService {
    /** Request the process ID of this service */
    int getPid();
    /**
     * Demonstrates some basic types thatyou can use as parameters
     * and return values in AIDL.
     */
    void basicTypes(intanInt,longaLong,booleanaBoolean,floataFloat,
            double aDouble,StringaString);
}

 

2.     实现接口

Android studio会自动生成AIDL对应的java文件，

/*
 * This file is auto-generated.  DO NOT MODIFY.
 * Original file:D:\\workspace\\AndroidStudioWorkspace\\AndroidDemo_N\\app\\src\\main\\aidl\\com\\ali\\yunos\\androiddemo_n\\services\\IRemoteService.aidl
 */
package com.ali.yunos.androiddemo_n.services;
// Declare any non-default types here withimport statements

public interface IRemoteServiceextendsandroid.os.IInterface
{
/** Local-sideIPC implementation stub class. */
public staticabstract class Stubextendsandroid.os.Binderimplementscom.ali.yunos.androiddemo_n.services.IRemoteService
{
private static final java.lang.StringDESCRIPTOR="com.ali.yunos.androiddemo_n.services.IRemoteService";
/** Constructthe stub at attach it to the interface. */
public Stub()
{
this.attachInterface(this,DESCRIPTOR);
}
/**
 * Cast an IBinder object into ancom.ali.yunos.androiddemo_n.services.IRemoteService interface,
 * generating a proxy if needed.
 */
public static com.ali.yunos.androiddemo_n.services.IRemoteServiceasInterface(android.os.IBinder obj)
{
if ((obj==null)) {
return null;
}
android.os.IInterface iin = obj.queryLocalInterface(DESCRIPTOR);
if (((iin!=null)&&(iininstanceofcom.ali.yunos.androiddemo_n.services.IRemoteService))){
return ((com.ali.yunos.androiddemo_n.services.IRemoteService)iin);
}
return new com.ali.yunos.androiddemo_n.services.IRemoteService.Stub.Proxy(obj);
}
@Override publicandroid.os.IBinderasBinder()
{
return this;
}
@Override public booleanonTransact(intcode,android.os.Parcel data,android.os.Parcel reply, intflags)throwsandroid.os.RemoteException
{
switch (code)
{
case INTERFACE_TRANSACTION:
{
reply.writeString(DESCRIPTOR);
return true;
}
case TRANSACTION_getPid:
{
data.enforceInterface(DESCRIPTOR);
int _result = this.getPid();
reply.writeNoException();
reply.writeInt(_result);
return true;
}
case TRANSACTION_basicTypes:
{
data.enforceInterface(DESCRIPTOR);
int _arg0;
_arg0 = data.readInt();
long _arg1;
_arg1 = data.readLong();
boolean _arg2;
_arg2 = (0!=data.readInt());
float _arg3;
_arg3 = data.readFloat();
double _arg4;
_arg4 = data.readDouble();
java.lang.String _arg5;
_arg5 = data.readString();
this.basicTypes(_arg0,_arg1,_arg2, _arg3,_arg4,_arg5);
reply.writeNoException();
return true;
}
}
return super.onTransact(code,data,reply, flags);
}
private static class Proxyimplementscom.ali.yunos.androiddemo_n.services.IRemoteService
{
private android.os.IBindermRemote;
Proxy(android.os.IBinder remote)
{
mRemote = remote;
}
@Override publicandroid.os.IBinderasBinder()
{
return mRemote;
}
public java.lang.StringgetInterfaceDescriptor()
{
return DESCRIPTOR;
}
@Override public intgetPid()throws android.os.RemoteException
{
android.os.Parcel _data = android.os.Parcel.obtain();
android.os.Parcel _reply =android.os.Parcel.obtain();
int _result;
try {
_data.writeInterfaceToken(DESCRIPTOR);
mRemote.transact(Stub.TRANSACTION_getPid,_data,_reply, 0);
_reply.readException();
_result = _reply.readInt();
}
finally {
_reply.recycle();
_data.recycle();
}
return _result;
}
/**
     * Demonstrates some basic types thatyou can use as parameters
     * and return values in AIDL.
     */
@Override public voidbasicTypes(intanInt, longaLong, booleanaBoolean, floataFloat, doubleaDouble,java.lang.String aString) throwsandroid.os.RemoteException
{
android.os.Parcel _data = android.os.Parcel.obtain();
android.os.Parcel _reply =android.os.Parcel.obtain();
try {
_data.writeInterfaceToken(DESCRIPTOR);
_data.writeInt(anInt);
_data.writeLong(aLong);
_data.writeInt(((aBoolean)?(1):(0)));
_data.writeFloat(aFloat);
_data.writeDouble(aDouble);
_data.writeString(aString);
mRemote.transact(Stub.TRANSACTION_basicTypes,_data,_reply, 0);
_reply.readException();
}
finally {
_reply.recycle();
_data.recycle();
}
}
}
static final int TRANSACTION_getPid= (android.os.IBinder.FIRST_CALL_TRANSACTION+0);
static final int TRANSACTION_basicTypes=(android.os.IBinder.FIRST_CALL_TRANSACTION+1);
}
public int getPid()throwsandroid.os.RemoteException;
/**
     * Demonstrates some basic types thatyou can use as parameters
     * and return values in AIDL.
     */
public void basicTypes(intanInt, longaLong, booleanaBoolean, floataFloat, doubleaDouble,java.lang.String aString) throwsandroid.os.RemoteException;
}

 

然后实现接口，

    private final IRemoteService.StubmBinder=new IRemoteService.Stub(){
        @Override
        public int getPid()throwsRemoteException {
//            return 0;
            return Process.myPid();
        }

        @Override
        public void basicTypes(intanInt, longaLong, booleanaBoolean, floataFloat, doubleaDouble,String aString) throwsRemoteException {
            Log.d(TAG,"basicTypes");
        }
    };

 

3.     public出去，这个重新定义一个文件，比如RemoteService.

public classRemoteServiceextendsService {
    private final static StringTAG="RemoteService";

    public RemoteService() {
    }

    @Override
    public IBinderonBind(Intent intent) {
        // TODO: Return the communication channel tothe service.
//        throw newUnsupportedOperationException("Not yet implemented");
        return mBinder;
    }

    @Override
    public void onCreate() {
        super.onCreate();
    }

    private final IRemoteService.StubmBinder= new IRemoteService.Stub(){
        @Override
        public int getPid()throwsRemoteException {
//            return 0;
            return Process.myPid();
        }

        @Override
        public void basicTypes(intanInt, longaLong, booleanaBoolean, floataFloat, doubleaDouble,String aString) throwsRemoteException {
            Log.d(TAG,"basicTypes");
        }
    };


}

 

 

client端：

public classMainActivityextendsAppCompatActivity {

    private static final StringTAG="MainActivity";

    ImageView mImg=null;
    Button mButton=null;
    boolean mBound =false;

    IRemoteService mService=null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        Log.d(TAG,"onCreate Thread Id = "+ Process.myTid());
        super.onCreate(savedInstanceState);

        LinearLayout mLayout = newLinearLayout(this);
        mLayout.setOrientation(LinearLayout.VERTICAL);
        mLayout.setLayoutParams(newLinearLayout.LayoutParams(
                ViewGroup.LayoutParams.MATCH_PARENT,ViewGroup.LayoutParams.MATCH_PARENT));
        mLayout.setBackgroundColor(Color.CYAN);
        setContentView(mLayout);

        mImg =newImageView(this);
        mImg.setLayoutParams(newLinearLayout.LayoutParams(400,400));
        mImg.setBackgroundColor(Color.RED);
        mLayout.addView(mImg);

        Button button = mButton=new Button(this);
        button.setText("click me");
        button.setLayoutParams(newLinearLayout.LayoutParams(
                ViewGroup.LayoutParams.WRAP_CONTENT,ViewGroup.LayoutParams.WRAP_CONTENT
        ));
        mLayout.addView(button);

        button.setOnClickListener(newView.OnClickListener() {
            @Override
            public void onClick(View v) {
                Log.d(TAG,"click button");
                if (mBound) {
                    try {
                        int pid =mService.getPid();
                        Log.d(TAG,"service pid = "+ pid);
                    } catch(RemoteException e) {
                       e.printStackTrace();
                    }
                }
            }
        });
    }

    @Override
    protected void onStart() {
        super.onStart();

        Intent intent = newIntent(this,RemoteService.class);
        bindService(intent,mServiceConn,Context.BIND_AUTO_CREATE);
    }

    @Override
    protected void onStop() {
        super.onStop();
        if (mBound) {
            unbindService(mServiceConn);
            mBound =false;
        }
    }

    ServiceConnection mServiceConn =newServiceConnection(){
        @Override
        public void onServiceConnected(ComponentName name,IBinder service) {
            Log.d(TAG,"onServiceConnected");
            mService = IRemoteService.Stub.asInterface(service);
            mBound =true;
        }

        @Override
        public void onServiceDisconnected(ComponentName name) {
            Log.d(TAG,"onServiceDisconnected");
            mBound =false;
        }
    };
}

 

 点击button的日志打印：

07-06 06:27:49.836: D/MainActivity(3944): onCreate Thread Id = 3944
07-06 06:27:51.060: D/MainActivity(3944): onServiceConnected
07-06 06:28:28.141: D/MainActivity(3944): click button
07-06 06:28:28.142: D/MainActivity(3944): service pid = 3967

可以看出，已经调用了service的接口，Done！