Android 的进程间通信 Binder——AIDL的入门使用（一）

进程间通信系列

AIDL的入门使用(一)

AIDL的入门使用(二)

AIDL的入门使用(三)

Messenger的入门使用

序言

什么概念都省了，直接看怎么使用，主要分两部分，一个是服务端，一个是客户端。更多使用请持续关注。

AIDL通信的服务端

1、创建AIDL 的服务端的Moudle ；

2、在aidl包下创建需要传递的对象Book类，并实现Parcelable 接口（使用Android Studio 的Parcelable 接口生成插件）

package com.ljp.aidl_server.aidl;import android.os.Parcel;import android.os.Parcelable;/** * Created by yuxue on 2017/11/28. */public class Book implements Parcelable {    public int id;    public String name;    public double price;    //省略set 、get、构造、toString等方法    @Override    public int describeContents() {        return 0;    }    @Override    public void writeToParcel(Parcel dest, int flags) {        dest.writeInt(this.id);        dest.writeString(this.name);        dest.writeDouble(this.price);    }    public Book() {    }    protected Book(Parcel in) {        this.id = in.readInt();        this.name = in.readString();        this.price = in.readDouble();    }    public static final Parcelable.Creator<Book> CREATOR = new Parcelable.Creator<Book>() {        @Override        public Book createFromParcel(Parcel source) {            return new Book(source);        }        @Override        public Book[] newArray(int size) {            return new Book[size];        }    };}

3、鼠标右键单击aidl包——>new ——>AIDL——>AIDL File——>输入接口名称：IMyAidlInterface——>Finish

//Book.aidl文件package com.ljp.aidl_server.aidl;//在这里一定要标注包名，与 IMyAidlInterface.aidl文件中的包名相同，否则编译报错//注意  parcelable的p字母是小写   ,声明已序列化的类parcelable Book; 

4、在新生成的aidl包上鼠标右键新建文件要传递的类名.adil文件，这里要传递的对象为Book类，因此新建Book.aidl,在Book.aidl文件中声明包名和已序列化对应的类。

5、编写IMyAidlInterface.aidl文件，声明客户端调用AIDL的接口，编写好IMyAidlInterface.aidl文件以后 Build——>Make Project（一定要先Make Project以后编译器才不会报错）

// IMyAidlInterface.aidlpackage com.ljp.aidl_server.aidl;// Declare any non-default types here with import statementsimport com.ljp.aidl_server.aidl.Book;//虽然在同一个包中，但还是要进行导包操作，否则会报错。interface IMyAidlInterface {    /**     * Demonstrates some basic types that you can use as parameters     * and return values in AIDL.     */    void basicTypes(int anInt, long aLong, boolean aBoolean, float aFloat,            double aDouble, String aString);    //编写客户端可以调用的AIDL接口，    void addBook(in Book book);//一定要加 in    List<Book> getBooks();    void setTag(in String tag);    String getTag();    void setNum(in int num);    int getNum();}

6、创建服务端的Service并编写内容，右键单击aidl包——>New ——> Service——> Service——>输入文件名AidlSerVerService,创建IMyAidlInterface.Stub的对象并在onBind方法中返回。（注：IMyAidlInterface.java文件有编译器在Make Project 过程中自动生成，即我们可以不编写前面的aidl文件，只需要编写IMyAidlInterface.java文件也是可以进行进程间通信的）

package com.ljp.aidl_server.aidl;import android.app.Service;import android.content.Intent;import android.os.IBinder;import android.os.RemoteException;import android.text.TextUtils;import java.util.ArrayList;import java.util.List;public class AidlSerVerService extends Service {    private List<Book> mBookList = new ArrayList<>();    private String tag = "empty";    private int num = -1;    IMyAidlInterface.Stub stub_binder = new IMyAidlInterface.Stub() {//IMyAidlInterface.Stub实际为android.os.Binder 的子类并实现了com.ljp.aidl_server.aidl.IMyAidlInterface接口        @Override        public void basicTypes(int anInt, long aLong, boolean aBoolean, float aFloat, double aDouble, String aString) throws RemoteException {        }        @Override        public void addBook(Book book) throws RemoteException {            synchronized (this) {//同步操作，有可能有多个客户端共同访问                if (book != null) {                    mBookList.add(book);                }            }        }        @Override        public List<Book> getBooks() throws RemoteException {            return mBookList;        }        @Override        public void setTag(String tag) throws RemoteException {            synchronized (this) {                if (!TextUtils.isEmpty(tag)) {                    AidlSerVerService.this.tag = tag;                }            }        }        @Override        public String getTag() throws RemoteException {            return tag;        }        @Override        public void setNum(int num) throws RemoteException {            synchronized (this) {                AidlSerVerService.this.num = num;            }        }        @Override        public int getNum() throws RemoteException {            return num;        }    };    @Override    public IBinder onBind(Intent intent) {        // TODO: Return the communication channel to the service.        return stub_binder;    }}

7、在AndroidMainfest文件中注册服务端的Service并对外暴露，至此服务端的代码就编写完成了。

        <!--process：单独为一个进程；enabled：启用；exported：对外暴露 ；        注：服务端的包名为：com.ljp.aidl_server，客户端绑定Service的时候是使用程序的包名，不是使用AidlSerVerService类的包名  -->        <service            android:name=".aidl.AidlSerVerService"            android:process=":remote"            android:enabled="true"            android:exported="true">            <intent-filter >                <action android:name="server.aidl.service.action"/>            </intent-filter>        </service>

AIDL通信的客户端

1、将服务端 main文件夹下的aidl文件夹复制到客户端的main文件夹下，将服务端的Book类复制到客户端的对应包名下，然后Build——>Make Project ；

2、测试调用服务端的AIDL接口进行通信；

package com.ljp.aidl_client;import android.content.ComponentName;import android.content.Intent;import android.content.ServiceConnection;import android.os.Bundle;import android.os.IBinder;import android.os.RemoteException;import android.support.v7.app.AppCompatActivity;import android.util.Log;import android.view.View;import com.ljp.aidl_server.aidl.Book;import com.ljp.aidl_server.aidl.IMyAidlInterface;import java.util.List;public class MainActivity extends AppCompatActivity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);    }    private IMyAidlInterface mService_face;    private static final String TAG = "Main_Client";    ServiceConnection mConnection = new ServiceConnection() {        @Override        public void onServiceConnected(ComponentName name, IBinder service) {            Log.e(TAG, "onServiceConnected: ");            mService_face = IMyAidlInterface.Stub.asInterface(service);        }        @Override        public void onServiceDisconnected(ComponentName name) {            Log.e(TAG, "onServiceDisconnected: ");        }    };    public void bindAidlService(View view) {        Intent intent_service = new Intent();        intent_service.setPackage("com.ljp.aidl_server"); //设置需要绑定的服务端的包名，不是服务端Service的包名        intent_service.setAction("server.aidl.service.action");//设置你所需调用服务的意图        boolean successful = bindService(intent_service, mConnection, BIND_AUTO_CREATE);        Log.e(TAG, "bindAidlService: successful=" + successful);    }    public void UnbindAidlService(View view) {        if(mConnection!=null){            unbindService(mConnection);            Log.e(TAG, "UnbindAidlService: ");        }    }    public void addBook_AidlService(View view) {        try {            if (mService_face != null) {                mService_face.addBook(new Book(0, "book0", 30.5));                Log.e(TAG, "addBook_AidlService: ");            }        } catch (RemoteException e) {            e.printStackTrace();        }    }    public void getBooks_AidlService(View view) {        try {            if (mService_face != null) {                List<Book> books = mService_face.getBooks();                Log.e(TAG, "addBook_AidlService: books[0]=" + books.get(0));            }        } catch (RemoteException e) {            e.printStackTrace();        }    }    public void setTag_AidlService(View view) {        try {            if (mService_face != null) {                mService_face.setTag("setTag_AidlService");                Log.e(TAG, "setTag_AidlService: ");            }        } catch (RemoteException e) {            e.printStackTrace();        }    }    public void getTag_AidlService(View view) {        try {            if (mService_face != null) {                String tag = mService_face.getTag();                Log.e(TAG, "getTag_AidlService: tag=" + tag);            }        } catch (RemoteException e) {            e.printStackTrace();        }    }    public void setNum_AidlService(View view) {        try {            if (mService_face != null) {                mService_face.setNum(27);                Log.e(TAG, "setNum_AidlService: ");            }        } catch (RemoteException e) {            e.printStackTrace();        }    }    public void getNum_AidlService(View view) {        try {            if (mService_face != null) {                int num = mService_face.getNum();                Log.e(TAG, "getNum_AidlService: num=" + num);            }        } catch (RemoteException e) {            e.printStackTrace();        }    }}

测试结果如下：

IMyAidlInterface.java 文件详解，实际有用的是这个文件，有编写的aidl文件经过编译器自动生成（注：可以单独编写该文件那就不需要aidl文件了）

package com.ljp.aidl_server.aidl;public interface IMyAidlInterface extends android.os.IInterface {    /**     * Stub是存根，Proxy是代理,Stub是服务端实现的存根，而Proxy则是Stub的代理。     * Local-side IPC implementation stub class.     */    public static abstract class Stub extends android.os.Binder implements com.ljp.aidl_server.aidl.IMyAidlInterface {        //Binder的唯一标识，一般使用类名标识        private static final java.lang.String DESCRIPTOR = "com.ljp.aidl_server.aidl.IMyAidlInterface";        /**         * Construct the stub at attach it to the interface.         */        public Stub() {            this.attachInterface(this, DESCRIPTOR);        }        /**         * 将服务端的Binder对象转换为客户端需要的AIDL接口类型的对象，         * 如果在同一个进程下的话，那么asInterface()将返回服务端的Stub对象本身，因为此时根本不需要跨进称通信，那么直接调用Stub对象的接口就可以了，返回的实现就是服务端的Stub实现，也就是根本没有跨进程通信；         * 如果不是同一个进程，那么asInterface()返回是Stub.Proxy对象，该对象持有着远程的Binder引用（服务端），因为现在需要跨进程通信，所以如果调用Stub.Proxy的接口的话，那么它们都将是IPC调用，它会通过调用Stub.Proxy的transact方法去与服务端通信         * Cast an IBinder object into an com.ljp.aidl_server.aidl.IMyAidlInterface interface,generating a proxy if needed.         *         * @param obj         * @return 若位于同一进程中则返回的是服务端的Stub对象本身，否则返回的是系统封装后的Stub.Proxy对象         */        public static com.ljp.aidl_server.aidl.IMyAidlInterface asInterface(android.os.IBinder obj) {            if ((obj == null)) {                return null;            }            android.os.IInterface iin = obj.queryLocalInterface(DESCRIPTOR);            if (((iin != null) && (iin instanceof com.ljp.aidl_server.aidl.IMyAidlInterface))) {                return ((com.ljp.aidl_server.aidl.IMyAidlInterface) iin);            }            return new com.ljp.aidl_server.aidl.IMyAidlInterface.Stub.Proxy(obj);        }        /**         * 返回当前的Binder对象，在客户端连接成功时使用:IMyAidlInterface iMyAidlInterface = IMyAidlInterface.Stub.asInterface(service);         * 检索与此接口相关联的绑定器对象。您必须使用这个而不是普通的cast，这样代理对象才能返回正确的结果。         *         * @return         */        @Override        public android.os.IBinder asBinder() {            return this;        }        /**         * 运行在服务端的Binder线程池中，当客户端发起跨进程请求时，远程请求会通过底层封装后交由此方法处理         * 默认实现是返回false的存根。您将希望覆盖此操作，以完成事务的适当解组。 如果你想调用这个，调用交易()。         *         * @param code         * @param data         * @param reply         * @param flags         * @return 如果返回false客户端就会请求失败可用作权限验证         * @throws android.os.RemoteException         */        @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_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;                }                case TRANSACTION_addBook: {                    data.enforceInterface(DESCRIPTOR);                    com.ljp.aidl_server.aidl.Book _arg0;                    if ((0 != data.readInt())) {                        _arg0 = com.ljp.aidl_server.aidl.Book.CREATOR.createFromParcel(data);//调用Book类中的Parcelable的工厂方法生成一个Book对象，下同                    } else {                        _arg0 = null;                    }                    this.addBook(_arg0);                    reply.writeNoException();                    return true;                }                case TRANSACTION_getBooks: {                    data.enforceInterface(DESCRIPTOR);                    java.util.List<com.ljp.aidl_server.aidl.Book> _result = this.getBooks();                    reply.writeNoException();                    reply.writeTypedList(_result);                    return true;                }                case TRANSACTION_setTag: {                    data.enforceInterface(DESCRIPTOR);                    java.lang.String _arg0;                    _arg0 = data.readString();                    this.setTag(_arg0);                    reply.writeNoException();                    return true;                }                case TRANSACTION_getTag: {                    data.enforceInterface(DESCRIPTOR);                    java.lang.String _result = this.getTag();                    reply.writeNoException();                    reply.writeString(_result);                    return true;                }                case TRANSACTION_setNum: {                    data.enforceInterface(DESCRIPTOR);                    int _arg0;                    _arg0 = data.readInt();                    this.setNum(_arg0);                    reply.writeNoException();                    return true;                }                case TRANSACTION_getNum: {                    data.enforceInterface(DESCRIPTOR);                    int _result = this.getNum();                    reply.writeNoException();                    reply.writeInt(_result);                    return true;                }            }            return super.onTransact(code, data, reply, flags);        }        /**         * 一个运行在客户端的代理，持有服务端的Binder应用         * Stub是存根，Proxy是代理,Stub是服务端实现的存根，而Proxy则是Stub的代理。         */        private static class Proxy implements com.ljp.aidl_server.aidl.IMyAidlInterface {            private android.os.IBinder mRemote;            Proxy(android.os.IBinder remote) {                mRemote = remote;            }            @Override            public android.os.IBinder asBinder() {                return mRemote;            }            public java.lang.String getInterfaceDescriptor() {                return DESCRIPTOR;            }            /**             * Demonstrates some basic types that you can use as parameters             * and return values in AIDL.             */            @Override            public void basicTypes(int anInt, long aLong, boolean aBoolean, float aFloat, double aDouble, java.lang.String aString) throws android.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();                }            }            @Override            public void addBook(com.ljp.aidl_server.aidl.Book book) throws android.os.RemoteException {                android.os.Parcel _data = android.os.Parcel.obtain();                android.os.Parcel _reply = android.os.Parcel.obtain();                try {                    _data.writeInterfaceToken(DESCRIPTOR);                    if ((book != null)) {                        _data.writeInt(1);                        book.writeToParcel(_data, 0);                    } else {                        _data.writeInt(0);                    }                    mRemote.transact(Stub.TRANSACTION_addBook, _data, _reply, 0);                    _reply.readException();                } finally {                    _reply.recycle();                    _data.recycle();                }            }            @Override            public java.util.List<com.ljp.aidl_server.aidl.Book> getBooks() throws android.os.RemoteException {                android.os.Parcel _data = android.os.Parcel.obtain();                android.os.Parcel _reply = android.os.Parcel.obtain();                java.util.List<com.ljp.aidl_server.aidl.Book> _result;                try {                    _data.writeInterfaceToken(DESCRIPTOR);                    mRemote.transact(Stub.TRANSACTION_getBooks, _data, _reply, 0);                    _reply.readException();                    _result = _reply.createTypedArrayList(com.ljp.aidl_server.aidl.Book.CREATOR);                } finally {                    _reply.recycle();                    _data.recycle();                }                return _result;            }            @Override            public void setTag(java.lang.String tag) throws android.os.RemoteException {                android.os.Parcel _data = android.os.Parcel.obtain();                android.os.Parcel _reply = android.os.Parcel.obtain();                try {                    _data.writeInterfaceToken(DESCRIPTOR);                    _data.writeString(tag);                    mRemote.transact(Stub.TRANSACTION_setTag, _data, _reply, 0);                    _reply.readException();                } finally {                    _reply.recycle();                    _data.recycle();                }            }            @Override            public java.lang.String getTag() 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_getTag, _data, _reply, 0);                    _reply.readException();                    _result = _reply.readString();                } finally {                    _reply.recycle();                    _data.recycle();                }                return _result;            }            @Override            public void setNum(int num) throws android.os.RemoteException {                android.os.Parcel _data = android.os.Parcel.obtain();                android.os.Parcel _reply = android.os.Parcel.obtain();                try {                    _data.writeInterfaceToken(DESCRIPTOR);                    _data.writeInt(num);                    mRemote.transact(Stub.TRANSACTION_setNum, _data, _reply, 0);                    _reply.readException();                } finally {                    _reply.recycle();                    _data.recycle();                }            }            @Override            public int getNum() 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_getNum, _data, _reply, 0);                    _reply.readException();                    _result = _reply.readInt();                } finally {                    _reply.recycle();                    _data.recycle();                }                return _result;            }        }        //声明binder接口的方法的ID，用于标志方法        static final int TRANSACTION_basicTypes = (android.os.IBinder.FIRST_CALL_TRANSACTION + 0);        static final int TRANSACTION_addBook = (android.os.IBinder.FIRST_CALL_TRANSACTION + 1);        static final int TRANSACTION_getBooks = (android.os.IBinder.FIRST_CALL_TRANSACTION + 2);        static final int TRANSACTION_setTag = (android.os.IBinder.FIRST_CALL_TRANSACTION + 3);        static final int TRANSACTION_getTag = (android.os.IBinder.FIRST_CALL_TRANSACTION + 4);        static final int TRANSACTION_setNum = (android.os.IBinder.FIRST_CALL_TRANSACTION + 5);        static final int TRANSACTION_getNum = (android.os.IBinder.FIRST_CALL_TRANSACTION + 6);    }    /**     * Demonstrates some basic types that you can use as parameters     * and return values in AIDL.     */    public void basicTypes(int anInt, long aLong, boolean aBoolean, float aFloat, double aDouble, java.lang.String aString) throws android.os.RemoteException;    //下面是Binder 通信的接口    public void addBook(com.ljp.aidl_server.aidl.Book book) throws android.os.RemoteException;    public java.util.List<com.ljp.aidl_server.aidl.Book> getBooks() throws android.os.RemoteException;    public void setTag(java.lang.String tag) throws android.os.RemoteException;    public java.lang.String getTag() throws android.os.RemoteException;    public void setNum(int num) throws android.os.RemoteException;    public int getNum() throws android.os.RemoteException;}