1、D02_d基於軟硬整合觀點(diǎn)撰寫你的第一個(gè)核心服務(wù)(d)By 高煥堂 C層擁有控制點(diǎn)的必備表現(xiàn)是：1. 從C創(chuàng)建Java對(duì)象2. 從C調(diào)用Java層函數(shù) 步驟4.1: 此時(shí)，myActivity必須透過(guò)JNI Native函數(shù)去綁定核心服務(wù)，然后由JNI Native函數(shù)在Java層誕生一個(gè)BpBinder對(duì)象的分身：即BinderProxy對(duì)象。如下圖： myActivity不宜含有native函數(shù)，于是委托sqr05來(lái)提供native函數(shù)，創(chuàng)建Java對(duì)象， 然后回傳接口給myActivity。 在Android里，提供了一個(gè)JNI Native 模塊， 內(nèi)涵一個(gè)javaObjectForI

2、Binder()函數(shù)，它能協(xié)助誕生Java層的BinderProxy對(duì)象，做為BpBinder對(duì)象的分身。 撰寫JNI Native模塊/ sqr05.java/ public class sqr05static System.loadLibrary(SQRS05_jni); public native final IBinder bindCoreService();/* com_misoo_service_sqr05.cpp */.sp m_ib; JNIEXPORT jobject JNICALLJava_com_misoo_service_sqr05_bindCoreService(JN

3、IEnv *env, jobject thiz)LOGE(bindCoreService);sp sm = defaultServiceManager(); m_ib = sm-getService(String16(misoo.sqr); LOGE(SM:getService %pn,sm.get();if (m_ib = 0)LOGW(SQRService not published, waiting.);return 0;jobject jbi = javaObjectForIBinder(env, m_ib);if (jbi = 0)LOGE(javaObjectForIBinder

4、jbi = 0);return 0; return jbi; 由javaObjectForIBinder()誕生Java層的BinderProxy對(duì)象。 BinderProxy對(duì)象里的mObject屬性指向BpBinder的IBinder接口。 JNI Native模塊里的gBinderProxyOffsets.mObject公用屬性存有BinderProxy類別里的mObject屬性的ID 值(不是指針)。如下圖： 于是，在從myActivity類別里，就能透過(guò)BinderProxy對(duì)象而調(diào)用JNI Native模塊， 轉(zhuǎn)而遠(yuǎn)距調(diào)用SQRService核心服務(wù)了。如下圖： 撰寫myActiv

5、ity/ myActivity.java/ndroid.os.IBinder;public class myActivity extends Activity implements OnClickListener private Button btn, btn2; Override/public void onClick(View v) switch(v.getId()case 101:sqr05 sqr = new sqr05();IBinder m_ib = sqr.bindCoreService(); int code = 0;Parcel data = Parcel.obtain();

6、 data.writeInt(11);Parcel reply = Parcel.obtain(); int flags = 0;try m_ib.transact(code, data, reply, flags); catch (Exception e) e.printStackTrace(); setTitle(Value = + String.valueOf(reply.readInt(); break;case 102:finish();break; myActivity執(zhí)行到指令：sqr05 sqr = new sqr05();IBinder m_ib = sqr.bindCore

7、Service(); 就委托sqr05來(lái)調(diào)用Native的bindCoreService()函數(shù)：Java_com_misoo_service_sqr05_bindCoreService(JNIEnv*, jobject) 這bindCoreService()函數(shù)內(nèi)含指令：sp sm = defaultServiceManager(); m_ib = sm-getService(String16(misoo.sqr); 于是，bindCoreService()函數(shù)綁定了SQRService核心服務(wù)。 再執(zhí)行指令：jobjectjbi = javaObjectForIBinder(env, m_ib); 這bindCoreService()函數(shù)就誕生了Java層的BinderProxy對(duì)象。 最后執(zhí)行到指令： return jbi; 這bindCoreService()函數(shù)就將BinderProxy對(duì)象的IBinder接口回傳給myActivity類