Android Service components in the new process binding (Bindservice) process

1, first of all, see two examples

(1) in-process

Client Side

public class Counterservice extends Service implements Icounterservice {  ... public class Counterbinder extends Bin Der {public  counterservice GetService () {  return counterservice.this;  }  }  ......}

Server Side

public class Mainactivity extends Activity implements Onclicklistener {  ... private serviceconnection Serviceconnection = new Serviceconnection () {public  void onserviceconnected (ComponentName className, IBinder Service) {  Counterservice = ((counterservice.counterbinder) service). GetService ();  LOG.I (Log_tag, "Counter Service Connected");  }  ......};  ......}

(1) Inter-process

Client Side

public class Remoteservice extends Service {private final static String TAG = "Remoteservice"; @Overridepublic ibinder Onbi nd (Intent Intent) {log.i (TAG, "executed Onbind"); return new Mybinder ();} Private class Mybinder extends remotewebpage.stub{@Overridepublic String Getcurrentpageurl () throws remoteexception{ return "http://www.cnblogs.com/hibraincol/";}}}

     

Server Side

Private class Myserviceconnection implements serviceconnection{@Overridepublic void onserviceconnected (componentname Name, IBinder service) {LOG.I (tag, "Establish connection ..."), Remotewebpage = RemoteWebPage.Stub.asInterface (service), try {LOG.D (tag, Remotewebpage.getcurrentpageurl ());} catch (RemoteException e) {//TODO auto-generated catch Blocke.printstacktrace ();}} @Overridepublic void onservicedisconnected (componentname name) {log.i (TAG, "onservicedisconnected ...");}}

Why one is

Counterservice = ((counterservice.counterbinder) service). GetService ();  

The other is

Remotewebpage = RemoteWebPage.Stub.asInterface (service);

The reason is that the first service is the Counterservice object, and the second service is the Binderproxy object, which points to the Mybinder object.

Why is there a difference between in-process and process? Please see:

In the 6th step, the parameter to be passed is the Binderproxy object.

The following code is executed in the process:

Case Binder_type_handle:case binder_type_weak_handle: {struct Binder_ref *ref = binder_get_        Ref (proc, fp->handle); ... if (Ref->node->proc = = Target_proc) {//same process if (Fp->type = = Binder_type_h                 Andle) Fp->type = Binder_type_binder;                 else Fp->type = Binder_type_weak_binder;                   Fp->binder = ref->node->ptr;                Fp->cookie = ref->node->cookie;                Binder_inc_node (ref->node, Fp->type = = Binder_type_binder, 0, NULL); if (Binder_debug_mask & binder_debug_transaction) printk (kern_info "ref%d desc%d-&gt ; Node%d u%p\n ", ref->debug_id, Ref->desc, ref->node->debug_id, ref->node->        PTR); } else {...}    } 

To convert intoCounterservice object to be prepared.

The following code is executed between processes:

Case Binder_type_handle:case binder_type_weak_handle: {struct Binder_ref *ref = binder_get_        Ref (proc, fp->handle);                                          ... if (Ref->node->proc = = Target_proc) {...} else {//different processes                    struct Binder_ref *new_ref;                New_ref = Binder_get_ref_for_node (Target_proc, Ref->node);                        if (new_ref = = NULL) {return_error = br_failed_reply;                Goto err_binder_get_ref_for_node_failed;                    } Fp->handle = new_ref->desc;                Binder_inc_ref (new_ref, Fp->type = = Binder_type_handle, NULL); if (Binder_debug_mask & binder_debug_transaction) printk (kern_info "ref%d desc%d-&gt ; Ref%d desc%d (node%d) \ n ", ref->debug_id, Ref->desC, new_ref->debug_id, New_ref->desc, ref->node->debug_id); }     }

To convert intoBinderproxy object to be prepared. At this point the Binderproxy object is the counter process, and theMybinder object is the Counterservice process. They pass data in a way that communicates between processes.