Android底层结构-SDKService线程知多少备课讲稿

1、Good is good, but better carries it.精益求精，善益求善。Android底层结构-SDKService线程知多少-Android底层结构：SDKService线程知多少总是由进程(Process)的主线程(Mainthread)执行SDK-Service(如下图的myService)对象。Android底层BinderSystem在binding-time会从该进程的Threadpool里启动一个线程来执行SDK-Service的Binder接口对象(如myBinder)。执行myActivity对象的线程与myBinder对象的线程会同步(Synchroni

2、ze)，让myActivity开发者觉得IPC远程呼叫、跨进程的两个线程，就如同单一线程一般。本文就LocalSDK-Service与RemoteSDK-Service两种来说明之。一、如果属于LocalService。-则myActivity与myService两者都是由mainthread所执行。亦即，两者是同一线程所执行。此情形下，两个类别里的函数都不宜太费时(例如不宜超过5秒钟)；但必要时可诞生子线程去执行费时的函数。/ac01.java(myActivity)packagecom.misoo.kx02b;importandroid.app.Activity;importandroid

3、.content.Intent;importandroid.graphics.Color;importandroid.os.Bundle;importandroid.view.View;importandroid.view.View.OnClickListener;importandroid.widget.Button;importandroid.widget.LinearLayout;importandroid.widget.TextView;publicclassac01extendsActivityimplementsOnClickListener/privatefinalintWC=L

4、inearLayout.LayoutParams.WRAP_CONTENT;privateTextViewtx;privateButtonbtn;OverridepublicvoidonCreate(BundlesavedInstanceState)super.onCreate(savedInstanceState);setContentView(R.layout.main);LinearLayoutlayout=newLinearLayout(this);layout.setOrientation(LinearLayout.VERTICAL);LinearLayout.LayoutParam

5、sparam=newLinearLayout.LayoutParams(150,40);param.topMargin=5;tx=newTextView(this);tx.setTextSize(16);tx.setTextColor(Color.BLUE);tx.setBackgroundResource(R.drawable.x_yellow);layout.addView(tx,param);btn=newButton(this);btn.setText(Exit);btn.setBackgroundResource(R.drawable.earth);btn.setOnClickLis

6、tener(this);layout.addView(btn,param);this.setContentView(layout);/-Stringtna=Thread.currentThread().getName();Thread.currentThread().setName(tna+-myActivity);/-myService.setUpdateListener(newUpdateUIListener();Intentsvc=newIntent(this,myService.class);startService(svc);OverrideprotectedvoidonDestro

7、y()super.onDestroy();Intentsvc=newIntent(this,myService.class);stopService(svc);classUpdateUIListenerimplementsIListenerpublicvoidupdate(Strings)tx.setText(s);publicvoidonClick(Viewv)this.finish();IListener.javapackagecom.misoo.kx02b;publicinterfaceIListenerpublicvoidupdate(Strings);/myService.javap

8、ackagecom.misoo.kx02b;importjava.util.Timer;importjava.util.TimerTask;importandroid.app.Service;importandroid.content.Intent;importandroid.os.Handler;importandroid.os.IBinder;importandroid.os.Message;publicclassmyServiceextendsServiceprivatestaticIListenerplis;privatestaticintk=0;privateTimertimer=n

9、ewTimer();privateStringtna;publicHandlerhandler=newHandler()publicvoidhandleMessage(Messagemsg)plis.update(tna);OverridepublicvoidonCreate()super.onCreate();tna=Thread.currentThread().getName();TimerTasktask=newTimerTask()Overridepublicvoidrun()handler.sendEmptyMessage(0);timer.schedule(task,1000,40

10、00);OverridepublicIBinderonBind(Intentintent)returnnull;publicstaticvoidsetUpdateListener(IListenerlistener)plis=listener;此程序输出：此结果说明了，myActivity与myService两者都是由mainthread所执行。二就一个SDKService而言，都是由mainthread执行myService的onCreate()、onBind()、onStart()等函数。然而，是由独立的线程来执行myBinder:onTransact()函数。因为BinderSystem

11、会从该进程的Threadpool里启动一个线程来执行SDK-Service的Binder接口对象(如myBinder)。二、如果属于RemoteService。-则myActivity与myService各在不同进程里执行，两者都是由各进程的mainthread所执行。亦即，两者是由不同的线程所执行。此情形下，两个类别里的函数也不宜太费时(例如不宜超过5秒钟)；但必要时可诞生子线程去执行较费时的函数。-所以由mainthread(myService所在的进程的mainthread)执行myService:onCreate()、myBinder:myBinder()和myService:onBi

12、nd()。-在Binding-time时，BinderSystem会建立myActivity与myBinder(即myService的Interface)之间的连结(Connection)。-在IPCcalling-time时，myActivity的线程与myBinder的线程会同步(Synchronize)，让myActivity开发者觉得IPC远程呼叫、跨进程的两个线程，就如同单一线程一般。-在送出IPCcall时，执行myBinder对象的线程会执行myBinder:onTransact()函数。兹写个程序来说明之，此程序执行时，出现下述画面：按下上一个Button,显示出mainthr

13、ead的执行路径：按下第二个Button,显示出mainthread执行onBind()函数：按下第三个Button,显示出BinderSystem启用独立的thread执行onTransact()函数：兹列出程序代码如下：/AndroidManifest.xml/ac01.javapackagecom.misoo.kx02c;importandroid.app.Activity;importandroid.content.ComponentName;importandroid.content.Context;importandroid.content.Intent;importandroid

14、.content.ServiceConnection;importandroid.graphics.Color;importandroid.os.Bundle;importandroid.os.IBinder;importandroid.os.Parcel;importandroid.view.View;importandroid.view.View.OnClickListener;importandroid.widget.Button;importandroid.widget.LinearLayout;importandroid.widget.TextView;publicclassac01

15、extendsActivityimplementsOnClickListenerprivatefinalintWC=LinearLayout.LayoutParams.WRAP_CONTENT;privatefinalintFP=LinearLayout.LayoutParams.FILL_PARENT;privateButtonbtn,btn2,btn3,btn4;publicTextViewtv;privateIBinderib=null;publicvoidonCreate(Bundleicicle)super.onCreate(icicle);LinearLayoutlayout=ne

16、wLinearLayout(this);layout.setOrientation(LinearLayout.VERTICAL);btn=newButton(this);btn.setId(101);btn.setText(startservice);btn.setBackgroundResource(R.drawable.heart);btn.setOnClickListener(this);LinearLayout.LayoutParamsparam=newLinearLayout.LayoutParams(120,50);param.topMargin=10;layout.addView

17、(btn,param);btn2=newButton(this);btn2.setId(102);btn2.setText(bindservice);btn2.setBackgroundResource(R.drawable.heart);btn2.setOnClickListener(this);layout.addView(btn2,param);btn3=newButton(this);btn3.setId(103);btn3.setText(IPCcall);btn3.setBackgroundResource(R.drawable.heart);btn3.setOnClickList

18、ener(this);layout.addView(btn3,param);btn4=newButton(this);btn4.setId(104);btn4.setText(exit);btn4.setBackgroundResource(R.drawable.heart);btn4.setOnClickListener(this);layout.addView(btn4,param);tv=newTextView(this);tv.setTextColor(Color.WHITE);tv.setText();LinearLayout.LayoutParamsparam2=newLinear

19、Layout.LayoutParams(FP,WC);param2.topMargin=10;layout.addView(tv,param2);setContentView(layout);/-Stringtna=Thread.currentThread().getName();Thread.currentThread().setName(tna+-ac01);/-privateServiceConnectionmConnection=newServiceConnection()publicvoidonServiceConnected(ComponentNameclassName,IBind

20、eribinder)ib=ibinder;publicvoidonServiceDisconnected(ComponentNameclassName);publicvoidonClick(Viewv)switch(v.getId()case101:startService(newIntent(com.misoo.kx02c.REMOTE_SERVICE);break;case102:bindService(newIntent(com.misoo.kx02c.REMOTE_SERVICE),mConnection,Context.BIND_AUTO_CREATE);break;case103:

21、Parcelpc=Parcel.obtain();Parcelpc_reply=Parcel.obtain();tryib.transact(1,pc,pc_reply,0);tv.setText(pc_reply.readString();catch(Exceptione)e.printStackTrace();break;case104:finish();break;/myActivity.javapackagecom.misoo.kx02c;importandroid.app.Activity;importandroid.graphics.Color;importandroid.os.B

22、undle;importandroid.view.View;importandroid.view.View.OnClickListener;importandroid.widget.Button;importandroid.widget.LinearLayout;importandroid.widget.TextView;publicclassmyActivityextendsActivityimplementsOnClickListenerprivatefinalintWC=LinearLayout.LayoutParams.WRAP_CONTENT;privatefinalintFP=Li

23、nearLayout.LayoutParams.FILL_PARENT;privateButtonbtn;publicTextViewtv;publicvoidonCreate(Bundleicicle)super.onCreate(icicle);LinearLayoutlayout=newLinearLayout(this);layout.setOrientation(LinearLayout.VERTICAL);btn=newButton(this);btn.setId(101);btn.setText(exit);btn.setBackgroundResource(R.drawable

24、.water);btn.setOnClickListener(this);LinearLayout.LayoutParamsparam=newLinearLayout.LayoutParams(120,50);param.topMargin=10;layout.addView(btn,param);tv=newTextView(this);tv.setTextColor(Color.WHITE);tv.setText();LinearLayout.LayoutParamsparam2=newLinearLayout.LayoutParams(FP,WC);param2.topMargin=10

25、;layout.addView(tv,param2);setContentView(layout);/-tv.setText(Thread.currentThread().getName()+-myActivity);/-publicvoidonClick(Viewv)switch(v.getId()case101:finish();break;/myService,javapackagecom.misoo.kx02c;importandroid.app.Service;importandroid.content.Intent;importandroid.os.Binder;importand

26、roid.os.IBinder;importandroid.os.Parcel;publicclassmyServiceextendsServiceprivateIBindermBinder=null;OverridepublicvoidonCreate()Thread.currentThread().setName(Thread.currentThread().getName()+-onCreate);mBinder=newmyBinder();OverridepublicvoidonStart(Intentintent,intstartId)Thread.currentThread().s

27、etName(Thread.currentThread().getName()+-onStart);Intenti=newIntent(getApplicationContext(),myActivity.class);i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);getApplicationContext().startActivity(i);OverridepublicIBinderonBind(Intentintent)Thread.currentThread().setName(Thread.currentThread().getName()+-o

28、nBind);Intentin=newIntent(this.getApplicationContext(),myActivity.class);in.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);startActivity(in);returnmBinder;publicclassmyBinderextendsBinderpublicmyBinder()Thread.currentThread().setName(Thread.currentThread().getName()+-myBinder);OverridepublicbooleanonTransa

29、ct(intcode,Parceldata,Parcelreply,intflags)throwsandroid.os.RemoteExceptionreply.writeString(Thread.currentThread().getName();returntrue;HYPERLINK/Topic.aspx?BoardID=11&TopicID=833t_blank返回：Android底层结构系列文章三*Activity线程与Service线程的同步-在Binding-time时，BinderSystem会建立myActivity与myBinder(即myService的Interfac

30、e)之间的连结(Connection)。-在IPCcalling-time时，myActivity的线程与myBinder的线程会同步(Synchronize)，让myActivity开发者觉得IPC远程呼叫、跨进程的两个线程，就如同单一线程一般。兹写个程序来说明之，此程序执行时，出现下述画面：按下之后，执行myActivity的主线程会等待myBinder线程，所以必须等待数秒钟之后，myActivity的主线程才会继续输出：count:1value:5字符串：按下之后，myActivity的主线程继续输出：count:1value:305字符串：以上说明了：myActivity的主线程会等

31、待myBinder线程。Connection#1和Connection#2连结到同一个myBinder对象。透过两条不同的Connection，可存取到一个myBinder物件里的values值。兹列出程序代码如下：/ac01packagecom.misoo.kx02c;importandroid.app.Activity;importandroid.content.ComponentName;importandroid.content.Context;importandroid.content.Intent;importandroid.content.ServiceConnection;im

32、portandroid.graphics.Color;importandroid.os.Bundle;importandroid.os.IBinder;importandroid.os.Parcel;importandroid.view.View;importandroid.view.View.OnClickListener;importandroid.widget.Button;importandroid.widget.LinearLayout;importandroid.widget.TextView;publicclassac01extendsActivityimplementsOnCl

33、ickListenerprivatefinalintWC=LinearLayout.LayoutParams.WRAP_CONTENT;privatefinalintFP=LinearLayout.LayoutParams.FILL_PARENT;privateButtonbtn,btn2,btn3;publicTextViewtv;privateIBinderib=null;privateIBinderib2=null;publicvoidonCreate(Bundleicicle)super.onCreate(icicle);LinearLayoutlayout=newLinearLayo

34、ut(this);layout.setOrientation(LinearLayout.VERTICAL);btn=newButton(this);btn.setId(101);btn.setText(IPCcallconn#1);btn.setBackgroundResource(R.drawable.heart);btn.setOnClickListener(this);LinearLayout.LayoutParamsparam=newLinearLayout.LayoutParams(120,50);param.topMargin=10;layout.addView(btn,param

35、);btn2=newButton(this);btn2.setId(102);btn2.setText(IPCcallconn#2);btn2.setBackgroundResource(R.drawable.heart);btn2.setOnClickListener(this);layout.addView(btn2,param);btn3=newButton(this);btn3.setId(103);btn3.setText(exit);btn3.setBackgroundResource(R.drawable.heart);btn3.setOnClickListener(this);

36、layout.addView(btn3,param);tv=newTextView(this);tv.setTextColor(Color.WHITE);tv.setText();LinearLayout.LayoutParamsparam2=newLinearLayout.LayoutParams(FP,WC);param2.topMargin=10;layout.addView(tv,param2);setContentView(layout);/-bindService(newIntent(com.misoo.kx02c.REMOTE_SERVICE),mConnection,Conte

37、xt.BIND_AUTO_CREATE);/-bindService(newIntent(com.misoo.kx02c.REMOTE_SERVICE),mConnection2,Context.BIND_AUTO_CREATE);/-privateServiceConnectionmConnection=newServiceConnection()publicvoidonServiceConnected(ComponentNameclassName,IBinderibinder)ib=ibinder;publicvoidonServiceDisconnected(ComponentNamec

38、lassName);privateServiceConnectionmConnection2=newServiceConnection()publicvoidonServiceConnected(ComponentNameclassName,IBinderibinder)ib2=ibinder;publicvoidonServiceDisconnected(ComponentNameclassName);publicvoidonClick(Viewv)switch(v.getId()case101:Parcelp=Parcel.obtain();Parcelp_reply=Parcel.obt

39、ain();tryib.transact(0,p,p_reply,0);tv.setText(p_reply.readString();catch(Exceptione)e.printStackTrace();break;case102:Parcelpc=Parcel.obtain();Parcelpc_reply=Parcel.obtain();tryib2.transact(1,pc,pc_reply,0);tv.setText(pc_reply.readString();catch(Exceptione)e.printStackTrace();break;case103:finish()

40、;break;/myServicepackagecom.misoo.kx02c;importandroid.app.Service;importandroid.content.Intent;importandroid.os.Binder;importandroid.os.IBinder;importandroid.os.Parcel;publicclassmyServiceextendsServiceprivatestaticintcount=0;OverridepublicIBinderonBind(Intentintent)count+;returnnewmyBinder();public

41、classmyBinderextendsBinderprivateintvalue=0;OverridepublicbooleanonTransact(intcode,Parceldata,Parcelreply,intflags)throwsandroid.os.RemoteExceptionif(code=0)value+=5;tryThread.sleep(8000);catch(InterruptedExceptione)/TODOAuto-generatedcatchblocke.printStackTrace();elseif(code=1)value+=300;reply.wri

42、teString(count:+String.valueOf(count)+value:+String.valueOf(value);returntrue;END*Service进程的ThreadPool-在Binding-time时，BinderSystem会建立myActivity与myBinder(即myService的Interface)之间的连结(Connection)。-在IPCcalling-time时，每次IPCcall，BinderSystem会从Service进程的Threadpool里启动一个Thread来对应myActivity的线程。兹写个范例：myActivity的

43、mainthread先诞生一个子线程发出IPC，Service进程则启动BinderThread#1来接待它。此myActivity子线程会等待BinderThread#1睡醒。myActivity的mainthread再诞生一个子线程发出IPC，Service进程则启动BinderThread#2来接待它。此myActivity子线程会等待BinderThread#2睡醒。myActivity的mainthread自己发出IPC，Service进程则启动BinderThread#3来接待它。兹列出程序代码：/ac01.javapackagecom.misoo.kx02c;importandr

44、oid.app.Activity;importandroid.content.ComponentName;importandroid.content.Context;importandroid.content.Intent;importandroid.content.ServiceConnection;importandroid.graphics.Color;importandroid.os.Bundle;importandroid.os.Handler;importandroid.os.IBinder;importandroid.os.Message;importandroid.os.Par

45、cel;importandroid.view.View;importandroid.view.View.OnClickListener;importandroid.widget.Button;importandroid.widget.LinearLayout;importandroid.widget.TextView;publicclassac01extendsActivityimplementsOnClickListenerprivatefinalintWC=LinearLayout.LayoutParams.WRAP_CONTENT;privatefinalintFP=LinearLayo

46、ut.LayoutParams.FILL_PARENT;privateButtonbtn,btn2;publicTextViewtv,tv2;privateIBinderib=null;privateHandlerh1,h2;publicvoidonCreate(Bundleicicle)super.onCreate(icicle);LinearLayoutlayout=newLinearLayout(this);layout.setOrientation(LinearLayout.VERTICAL);btn=newButton(this);btn.setId(101);btn.setText

47、(createthreads);btn.setBackgroundResource(R.drawable.heart);btn.setOnClickListener(this);LinearLayout.LayoutParamsparam=newLinearLayout.LayoutParams(120,50);param.topMargin=10;layout.addView(btn,param);btn2=newButton(this);btn2.setId(102);btn2.setText(exit);btn2.setBackgroundResource(R.drawable.hear

48、t);btn2.setOnClickListener(this);layout.addView(btn2,param);tv=newTextView(this);tv.setTextColor(Color.WHITE);tv.setText();LinearLayout.LayoutParamsparam2=newLinearLayout.LayoutParams(FP,WC);param2.topMargin=10;layout.addView(tv,param2);tv2=newTextView(this);tv2.setTextColor(Color.WHITE);tv2.setText

49、();layout.addView(tv2,param2);setContentView(layout);/-Intentin=newIntent(com.misoo.kx02c.REMOTE_SERVICE);in.putExtra(key,0);bindService(in,mConnection,Context.BIND_AUTO_CREATE);privateServiceConnectionmConnection=newServiceConnection()publicvoidonServiceConnected(ComponentNameclassName,IBinderibind

50、er)ib=ibinder;publicvoidonServiceDisconnected(ComponentNameclassName);publicvoidonClick(Viewv)switch(v.getId()case101:h1=newHandler()publicvoidhandleMessage(Messagemsg)tv.setText(String)msg.obj);Threadt1=newThread(newTask();t1.start();/-tryThread.sleep(1000);catch(InterruptedExceptione1)/TODOAuto-ge

51、neratedcatchblocke1.printStackTrace();/-h2=newHandler()publicvoidhandleMessage(Messagemsg)tv2.setText(String)msg.obj);Threadt2=newThread(newTask2();t2.start();Parcelpc=Parcel.obtain();Parcelpc_reply=Parcel.obtain();tryib.transact(2,pc,pc_reply,0);setTitle(pc_reply.readString();catch(Exceptione)e.pri

52、ntStackTrace();break;case102:finish();break;/-classTaskimplementsRunnablepublicvoidrun()Parcelpc=Parcel.obtain();Parcelpc_reply=Parcel.obtain();tryib.transact(0,pc,pc_reply,0);Messagem=h1.obtainMessage(1,1,1,pc_reply.readString();h1.sendMessage(m);catch(Exceptione)e.printStackTrace();classTask2imple

53、mentsRunnablepublicvoidrun()Parcelpc=Parcel.obtain();Parcelpc_reply=Parcel.obtain();tryib.transact(1,pc,pc_reply,0);Messagem=h2.obtainMessage(1,1,1,pc_reply.readString();h2.sendMessage(m);catch(Exceptione)e.printStackTrace();/myBinder.javapackagecom.misoo.kx02c;importandroid.os.Binder;importandroid.

54、os.Parcel;publicclassmyBinderextendsBinderprivateintid=0;publicmyBinder(intidd)id=idd;OverridepublicbooleanonTransact(intcode,Parceldata,Parcelreply,intflags)throwsandroid.os.RemoteExceptionif(code!=2)tryThread.sleep(8000);catch(InterruptedExceptione)/TODOAuto-generatedcatchblocke.printStackTrace();

55、reply.writeString(Thread.currentThread().getName();/elseif(id=200)/reply.writeString(Thread.currentThread().getName()+-conn.#1);returntrue;/myService.javapackagecom.misoo.kx02c;importandroid.app.Service;importandroid.content.Intent;importandroid.os.IBinder;publicclassmyServiceextendsServiceprivatemy

56、Bindermb;OverridepublicvoidonCreate()mb=newmyBinder(100);OverridepublicIBinderonBind(Intentintent)returnmb;HYPERLINK/Topic.aspx?BoardID=11&TopicID=833t_blank返回：Android底层结构系列文章五*ToBind到Service的不同Interface-如果从Binder衍生了myBinder1、myBinder2和myBinder3等子类时，如何替myService选择适当的myBinder接口类别呢？-如果连续呼叫bindService(

57、)两次，会bind到同一个myBinder物件。-如果想Bind到另一个myBinder接口类别之对象，可先unbind()，就会呼叫到onBind()函数，来决定bind到哪一个对象。兹写个范例：按下会呼叫onBind()而绑到myBinder1的对象。再按下，就出现：由于Connection1已经绑定了myBinder1的对象。继续按下就还是Bind到myBinder1的对象(不会呼叫onBind()函数)，按下，就出现：继续按下，先unbind掉myBinder1的对象，再按下，会呼叫onBind()而绑到myBinder3的对象。再按下，就出现：兹列出程序代码/ac01packagec

58、om.misoo.kx02c;importandroid.app.Activity;importandroid.content.ComponentName;importandroid.content.Context;importandroid.content.Intent;importandroid.content.ServiceConnection;importandroid.graphics.Color;importandroid.os.Bundle;importandroid.os.IBinder;importandroid.os.Parcel;importandroid.view.Vi

59、ew;importandroid.view.View.OnClickListener;importandroid.widget.Button;importandroid.widget.LinearLayout;importandroid.widget.TextView;publicclassac01extendsActivityimplementsOnClickListenerprivatefinalintWC=LinearLayout.LayoutParams.WRAP_CONTENT;privatefinalintFP=LinearLayout.LayoutParams.FILL_PARE

60、NT;privateButtonbtn,btn2,btn3,btn4,btn5;publicTextViewtv;privateIBinderib=null;publicvoidonCreate(Bundleicicle)super.onCreate(icicle);LinearLayoutlayout=newLinearLayout(this);layout.setOrientation(LinearLayout.VERTICAL);btn=newButton(this);btn.setId(101);btn.setText(bind-1);btn.setBackgroundResource