java - Android getSystemService(Context.USB_SERVICE) error -

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i'm new @ android , i'm trying use android usb send data. tried use example code 

// usbmanager android. usbmanager manager = (usbmanager) getsystemservice(context.usb_service);  // find first available driver. usbserialdriver driver = usbserialprober.acquire(manager);  if (driver != null) {   driver.open();   try {     driver.setbaudrate(115200);      byte buffer[] = new byte[16];     int numbytesread = driver.read(buffer, 1000);     log.d(tag, "read " + numbytesread + " bytes.");   } catch (ioexception e) {     // deal error.   } {     driver.close();   }  }

and i'm getting error

the method getsystemservice(string) undefined type tcpclient

i'm not sure if i'm missing points. great. i'm using eclipse juno , jdk 1.7.

getsystemservice(string) method defined context class: context#getsystemservice(string). since activity subclass of context, using this.getsystemservice(string) or getsystemservice(string) works fine inside activity.

but, seems trying use method inside class named tcpclient. , error pointing out tcpclient#getsystemservice(string) not defined: correct.

you should either pass activity's context tcpclientand use as:

usbmanager manager = (usbmanager)                         passedcontext.getsystemservice(context.usb_service);

or if tcpclient inner class activity, following should work too:

usbmanager manager = (usbmanager)                    youractivityname.this.getsystemservice(context.usb_service);

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