Android framwork service添加(manager 遠程調service，service jni調native code)

在平常android應用開發中，多數只是調framwork中的API進行application layer的coding，而在系統開發中可能會自己添加系統服務；
系統服務如任何添加，服務如何調native code，以及service如何被manager調用...這裡我給出一個結果驗證的demo。

1、實現編寫native code，framwork/base/services/jni/com_android_server_VirtualInputService.cpp;

以下是會使用到的native 函數，以及register_android_server_VirtualInputService；具體實現就不在詳講了。

static JNINativeMethod method_table[] = {
    {"native_open",             "()I",(void *)android_server_VirtualInputService_open},
    {"native_close",            "()Z",  (void *)android_server_VirtualInputService_close},
    {"native_sendir",       "(II)Z",  (void *)android_server_VirtualInputService_sendir},
};
   
+int register_android_server_VirtualInputService(JNIEnv *env)
+{
+    jclass clazz = env->FindClass("com/android/server/VirtualInputService");
+    if (clazz == NULL) {
+        ALOGE("Can't find com/android/server/VirtualInputService");
+        return -1;
+    }
+	
+    return jniRegisterNativeMethods(env, "com/android/server/VirtualInputService",
+            method_table, NELEM(method_table));
+}
+};

2、base/services/jni/onload.cpp中添加register_android_server_VirtualInputService

 int register_android_server_SerialService(JNIEnv* env);
+int register_android_server_VirtualInputService(JNIEnv* env);
 int register_android_server_UsbDeviceManager(JNIEnv* env);
 
      register_android_server_SerialService(env);
+	register_android_server_VirtualInputService(env);
     register_android_server_InputApplicationHandle(env);

3、mk中添加com_android_server_VirtualInputService，使其被編譯到

+++ base/services/jni/Android.mk	(working copy)
@@ -16,6 +16,7 @@
     com_android_server_VibratorService.cpp \
     com_android_server_location_GpsLocationProvider.cpp \
     com_android_server_connectivity_Vpn.cpp \
+    com_android_server_VirtualInputService.cpp \
     onload.cpp

4、service添加： base/services/java/com/android/server/VirtualInputService.java
其必須繼承IVirtualInputManager.Stub使其能被遠程調用；
聲明native方法：private native static int native_open();
private native static boolean native_close();
private native static boolean native_sendir(int keycode, int type);

+package com.android.server;
+
+import android.content.Context;
+import android.hardware.input.IVirtualInputManager;
+import android.util.Log;
+
+import java.io.File;
+import java.util.ArrayList;
+
+public class VirtualInputService extends IVirtualInputManager.Stub {
+    private static final String TAG = "VirtualInputManager";
+
+    private final Context mContext;
+    private int mVirtualInputFd = -1;
+
+    public VirtualInputService(Context context) {
+        mContext = context;
+		if(mVirtualInputFd == -1){
+        	mVirtualInputFd = native_open();
+			Log.d(TAG, "mVirtualInputFd:"+mVirtualInputFd);
+		}else
+			Log.d(TAG, "mVirtualInputFd1:"+mVirtualInputFd);
+
+    }
+
+	public boolean SendIR(int keycode){
+		if(mVirtualInputFd > 0)
+		{	
+			Log.d(TAG, "Service SendIR:"+keycode);
+			return native_sendir(keycode,0);
+		}
+		else 
+			return false;
+	}
+	
+    private native static int native_open();
+	private native static boolean native_close();
+	private native static boolean native_sendir(int keycode, int type);
+
+}  

5、base/services/java/com/android/server/SystemServer.java中添加新service

   SerialService serial = null;
+  VirtualInputService VirtualInput = null;
    TwilightService twilight = null;

             try {
+                Slog.i(TAG, "VirtualInput Service");
+                VirtualInput = new VirtualInputService(context);
+                ServiceManager.addService(Context.VIRTUALINPUT_SERVICE, VirtualInput);
+            } catch (Throwable e) {
+                Slog.e(TAG, "Failure starting VirtualInputService", e);
+            }
+			
+            try {
                 Slog.i(TAG, "Twilight Service");
                 twilight = new TwilightService(context);
             } catch (Throwable e) {

6、添加aidl接口：base/core/java/android/hardware/input/IVirtualInputManager.aidl

+package android.hardware.input;
+
+
+/** @hide */
+interface IVirtualInputManager
+{
+	boolean SendIR(int keycode);
+}

7、實現IVirtualInputManager.java;base/core/java/android/hardware/input/VirtualInputManager.java

+package android.hardware.input;
+
+import android.app.PendingIntent;
+import android.content.Context;
+import android.os.Bundle;
+import android.os.ParcelFileDescriptor;
+import android.os.RemoteException;
+import android.os.SystemProperties;
+import android.util.Log;
+
+import java.io.IOException;
+import java.util.HashMap;
+
+/**
+ * @hide
+ */
+public class VirtualInputManager {
+    private static final String TAG = "VirtualInputManager";
+
+    private final Context mContext;
+    private final IVirtualInputManager mService;
+
+    /**
+     * {@hide}
+     */
+    public VirtualInputManager(Context context, IVirtualInputManager service) {
+        mContext = context;
+        mService = service;
+		Log.d(TAG,"VirtualInputManager");
+    }
+
+	public boolean SendIR(int keycode) throws android.os.RemoteException{
+		Log.d(TAG,"keycode:"+keycode);
+		return mService.SendIR(keycode);
+	}
+}

8.framwork/base/Android.mk

 	core/java/android/hardware/input/IInputManager.aidl \
+	core/java/android/hardware/input/IVirtualInputManager.aidl \
 	core/java/android/hardware/input/IInputDevicesChangedListener.aidl \

9、base/core/java/android/content/Context.java 中添加系統獲取服務的標示

+    public static final String VIRTUALINPUT_SERVICE = "virtualinput";

10、base/core/java/android/app/ContextImpl.java

+        registerService(VIRTUALINPUT_SERVICE, new ServiceFetcher() {
+                public Object createService(ContextImpl ctx) {
+                    IBinder b = ServiceManager.getService(VIRTUALINPUT_SERVICE);
+                    return new VirtualInputManager(ctx, IVirtualInputManager.Stub.asInterface(b));
+                }});
+				

以上就是添加一個完整的service的步驟了...