2023學(xué)年完整公開(kāi)課版繼承Binder類

北京電子科技職業(yè)學(xué)院移動(dòng)應(yīng)用軟件開(kāi)發(fā)（基于Android平臺(tái)）01繼承Binder類繼承Binder類如果服務(wù)僅用于本地應(yīng)用程序并且不必跨進(jìn)程工作，則開(kāi)發(fā)人員可以實(shí)現(xiàn)自己的Binder類來(lái)為客戶端提供訪問(wèn)服務(wù)公共方法的方式。注意：這僅當(dāng)客戶端與服務(wù)位于同一個(gè)應(yīng)用程序和進(jìn)程時(shí)才有效。

實(shí)現(xiàn)方法：1、在Service中創(chuàng)建一個(gè)Binder的實(shí)例：這個(gè)實(shí)例包含client可以調(diào)用的公共方法；這個(gè)實(shí)例返回當(dāng)前Service對(duì)象（該Service實(shí)例包含client可以調(diào)用的公共方法）這個(gè)實(shí)例返回Service類中的一個(gè)類對(duì)象，而這個(gè)類對(duì)象包含client可以調(diào)用的公共方法繼承Binder類實(shí)現(xiàn)步驟

實(shí)現(xiàn)方法：2、在Service的onBind函數(shù)中返回這個(gè)Binder實(shí)例3、在client端的onServiceConnected方法中獲得這個(gè)Binder實(shí)例，并通過(guò)這個(gè)Binder實(shí)例調(diào)用Service端的公共方法。繼承Binder類實(shí)現(xiàn)步驟

publicclassBindServiceWithIBinderextendsService{privatestaticfinalStringTAG="BindServiceWithIBinder";privatefinalMyIBindermyIBinder=newMyIBinder();/***bindService()時(shí)，調(diào)用的是這個(gè)方法，而非onStartCommnad()方法*/@OverridepublicIBinderonBind(Intentintent){//在主Activity上的TextView中打印出一行LOGMyServiceActivity.vh.sendMessage(MyServiceActivity.createMessage(MyServiceActivity.UPDATE_VIEW,TAG+"---->onBind"));returnmyIBinder;}

繼承Binder類實(shí)現(xiàn)步驟@OverridepublicvoidonCreate(){MyServiceActivity.vh.sendMessage(MyServiceActivity.createMessage(MyServiceActivity.UPDATE_VIEW,TAG+"---->onCreate"));}@OverridepublicvoidonDestroy(){MyServiceActivity.vh.sendMessage(MyServiceActivity.createMessage(MyServiceActivity.UPDATE_VIEW,TAG+"---->onDestroy"));}

繼承Binder類實(shí)現(xiàn)步驟@OverridepublicvoidonRebind(Intentintent){MyServiceActivity.vh.sendMessage(MyServiceActivity.createMessage(MyServiceActivity.UPDATE_VIEW,TAG+"---->onRebind"));}@OverridepublicintonStartCommand(Intentintent,intflags,intstartId){MyServiceActivity.vh.sendMessage(MyServiceActivity.createMessage(MyServiceActivity.UPDATE_VIEW,TAG+"---->onStartCommand"));returnSTART_STICKY;}

繼承Binder類實(shí)現(xiàn)步驟@OverridepublicbooleanonUnbind(Intentintent){MyServiceActivity.vh.sendMessage(MyServiceActivity.createMessage(MyServiceActivity.UPDATE_VIEW,TAG+"---->onUnbind"));returnsuper.onUnbind(intent);}

繼承Binder類實(shí)現(xiàn)步驟/***聲明一個(gè)Binder類的實(shí)現(xiàn)類，供在onBind()方法中返回該類的一個(gè)實(shí)例*/publicclassMyIBinderextendsBinder{publicServicegetService(){MyServiceActivity.vh.sendMessage(MyServiceActivity.createMessage(MyServiceActivity.UPDATE_VIEW,"BindServiceWithIBinder.MyIBinder.getService()"));returnBindServiceWithIBinder.this;}}繼承Binder類實(shí)現(xiàn)步驟//service提供的公共方法，在activity中可以調(diào)用publicvoiddownload(){try{MyServiceActivity.vh.sendMessage(MyServiceActivity.createMessage(MyServiceActivity.UPDATE_VIEW,TAG+"---->download():文件下載中..."));Thread.sleep(3000);MyServiceActivity.vh.sendMessage(MyServiceActivity.createMessage(MyServiceActivity.UPDATE_VIEW,TAG+"---->download():文件下載完成..."));