Java Question Connecting to PTV navigator

[JDS]

We are trying to connect to an application called PTV navigator.
That application works with an remote interface which is a service to interact with PTV navigator.

There are three seps to the navigation service.
1. Create a service connection
2. Bind to the service
3. Receive/send messages from/to the service

public  void BindToPTV() {
     
      /*The package name of the service is always "com.ptvag.navigation.ri.RIService", the componentName may be different*/
      String componentName = "com.ptvag.navigator.app";
      /*String componentName = "com.ptvag.navigatortruckplay.app";
      String componentName = "com.ptvag.navigatorfleetplay.app";*/
      String serviceName = "com.ptvag.navigation.ri.RIService"; 
      Intent i = new Intent();
     i.setClassName(componentName, serviceName);
     boolean rc = getApplicationContext().bindService(i, serviceConnection, Context.BIND_AUTO_CREATE);
   }

At the moment we can't get passed step 2. We've compiled the java-code to an library without any problem. But when we call BindToPTV the B4A-applications stops working. The line "getApplicationContext().bindservice...." generates an error:

java.lang.NullPointerException
at android.content.ContextWrapper.getApplicationContext(ContextWrapper.java:109)
at jds.b4a.ptv.PTV.BindToNav(PTV.java:152)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at anywheresoftware.b4a.shell.Shell.runVoidMethod(Shell.java:680)
at anywheresoftware.b4a.shell.Shell.raiseEventImpl(Shell.java:308)
at anywheresoftware.b4a.shell.Shell.raiseEvent(Shell.java:238)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at anywheresoftware.b4a.ShellBA.raiseEvent2(ShellBA.java:121)
at b4a.example.main.afterFirstLayout(main.java:98)
at b4a.example.main.access$100(main.java:16)
at b4a.example.main$WaitForLayout.run(main.java:76)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:212)
at android.app.ActivityThread.main(ActivityThread.java:5135)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:877)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:693)
at dalvik.system.NativeStart.main(Native Method)


Any thoughts?

 

[Erel]

What is the class type? It should not be Activity or Service.
Instead pass a BA object as one of the parameters and it will allow you to access the context.

 

[JDS]

Erel,

It used to be:

public class PTV extends activity {

I changed it to:

public class PTV {

At that moment the lines give some issues.

getApplicationContext().bindService(i,serviceConnection, Context.BIND_AUTO_CREATE);/*It says:"The method getApplicationContext() is undefined for the type PTV".*/
/* or the line*/
anywheresoftware.b4a.BA.applicationContext(i,serviceConnection,Context.BIND_AUTO_CREATE);/*It says:"The method getApplicationContext() is undefined for the type BA".*/

Any thoughts about the above?

 

[Erel]

You are missing bindService in the second line.

 

[JDS]

Thanks Erel, I overlooked that one.

I changed a few things but I can't get it to work.

I call the public void addstation. The first thing it should do is to bind to the service (which never happens).

public void AddStation(String Name, String x, String y)
   {
      BindToPTV();
 }

@return 
    */
   private void BindToPTV() {
     
    //  final String apps[] = getServiceApps();
      String componentName = "com.ptvag.navigation.app";
      Common.Log(componentName);
      String serviceName = "com.ptvag.navigation.ri.RIService"; 
      Intent i = new Intent();
      i.setClassName(componentName, serviceName);
      anywheresoftware.b4a.BA.applicationContext.bindService(i,serviceConnection,Context.BIND_AUTO_CREATE);
      if (isBound()) Common.Log("Connected");
   }

You can see that there is a line Common.Log("Connected"), that one gets skipped. Bound is false.
Below you find the serviceconnection. If I put an logging in there it isn't executed.

Any thoughts? The library is compiling without errors.

/** Class for interacting with the main interface of the service. */
   protected ServiceConnection serviceConnection = new ServiceConnection()
   {
      public void onServiceConnected(ComponentName className, IBinder service)
      {
         // This is called when the connection with the service has been
         // established, giving us the object we can use to
         // interact with the service. We are communicating with the
         // service using a Messenger, so here we get a client-side
         // representation of that from the raw IBinder object.
         foreignService = new Messenger(service);
         bound = true;
      }

      public void onServiceDisconnected(ComponentName className)
      {
         // This is called when the connection with the service has been
         // unexpectedly disconnected -- that is, its process crashed.
         foreignService = null;
         bound = false;
         
      }
   };

 

[Erel]

Are you able to run the Java code they posted? Does it work?

 

[JDS]

Yes but that is a complete program with buttons.
I only need the application to start and drive to a certain point (x y coordinates)

 

[Erel]

Sorry but you will need to find someone who can create a wrapper for this library.

It is difficult to say why it doesn't work.