eclipse - Fatal Exception : Main android -

with friends, we're working in project , need create android application. (i specify, i'm beginner @ programming in java).

so start i've follow tutorial (http://www.buildcircuit.com/sensorgraph-using-android-amarino-and-arduino/) explain how create connection enter arduino (microcontroller) , arduino amarino (bluetooth).

the program retrieves value of variable voltage , displays on phone.

but i've trouble, program doesn't work. when uploading on phone, show black window error message "unfortunately, sensorgraph2 has stopped" don't know can do.

this sensorgrpah.java:

package edu.mit.media.hlt.sensorgraph; import android.app.activity;     import android.content.broadcastreceiver;     import android.content.context;     import android.content.intent;     import android.content.intentfilter;     import android.os.bundle;     import android.widget.textview;     import at.abraxas.amarino.amarino;     import at.abraxas.amarino.amarinointent;   public class sensorgraph extends activity {       private static final string device_address =  "00:15:ff:f2:0f:a8";      private graphview mgraph;      private textview mvaluetv;      private arduinoreceiver arduinoreceiver = new arduinoreceiver();       @override     public void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);          setcontentview(r.layout.main);           mgraph = (graphview)findviewbyid(r.id.graph);         mvaluetv = (textview) findviewbyid(r.id.value);          mgraph.setmaxvalue(1024);     }      @override     protected void onstart() {         super.onstart();          registerreceiver(arduinoreceiver, new intentfilter(amarinointent.action_received));           amarino.connect(this, device_address);     }       @override     protected void onstop() {         super.onstop();           amarino.disconnect(this, device_address);           unregisterreceiver(arduinoreceiver);     }        public class arduinoreceiver extends broadcastreceiver {          @override         public void onreceive(context context, intent intent) {             string data = null;               final int datatype = intent.getintextra(amarinointent.extra_data_type, -1);               if (datatype == amarinointent.string_extra){                 data = intent.getstringextra(amarinointent.extra_data);                  if (data != null){                     mvaluetv.settext(data);                     try {                          final int sensorreading = integer.parseint(data);                         mgraph.adddatapoint(sensorreading);                     }                      catch (numberformatexception e) { /* oh data not integer */ }                 }             }         }     }  } 

and main.xml

<?xml version="1.0" encoding="utf-8"?> <linearlayout xmlns:android="http://schemas.android.com/apk/res/android"     android:orientation="vertical"     android:layout_width="fill_parent"     android:layout_height="fill_parent"     >     <edu.mit.media.hlt.sensorgraph.graphview         android:id="@+id/graph"         android:layout_width="fill_parent"          android:layout_height="fill_parent"         android:layout_weight="4"     />     <textview          android:id="@+id/value"         android:layout_width="fill_parent"          android:layout_height="fill_parent"         android:layout_weight="6"         android:text="@string/hello"         android:textsize="40sp"         android:gravity="center"         android:background="#fff"     /> </linearlayout> 

and logcat when i'm trying upload on phone

05-14 00:30:56.640: e/androidruntime(29568): fatal exception: main 05-14 00:30:56.640: e/androidruntime(29568): java.lang.noclassdeffounderror: at.abraxas.amarino.amarino 05-14 00:30:56.640: e/androidruntime(29568):    @ edu.mit.media.hlt.sensorgraph.sensorgraph.onstart(sensorgraph.java:71) 05-14 00:30:56.640: e/androidruntime(29568):    @ android.app.instrumentation.callactivityonstart(instrumentation.java:1167) 05-14 00:30:56.640: e/androidruntime(29568):    @ android.app.activity.performstart(activity.java:5216) 05-14 00:30:56.640: e/androidruntime(29568):    @ android.app.activitythread.performlaunchactivity(activitythread.java:2073) 05-14 00:30:56.640: e/androidruntime(29568):    @ android.app.activitythread.handlelaunchactivity(activitythread.java:2125) 05-14 00:30:56.640: e/androidruntime(29568):    @ android.app.activitythread.access$600(activitythread.java:140) 05-14 00:30:56.640: e/androidruntime(29568):    @ android.app.activitythread$h.handlemessage(activitythread.java:1227) 05-14 00:30:56.640: e/androidruntime(29568):    @ android.os.handler.dispatchmessage(handler.java:99) 05-14 00:30:56.640: e/androidruntime(29568):    @ android.os.looper.loop(looper.java:137) 05-14 00:30:56.640: e/androidruntime(29568):    @ android.app.activitythread.main(activitythread.java:4898) 05-14 00:30:56.640: e/androidruntime(29568):    @ java.lang.reflect.method.invokenative(native method) 05-14 00:30:56.640: e/androidruntime(29568):    @ java.lang.reflect.method.invoke(method.java:511) 05-14 00:30:56.640: e/androidruntime(29568):    @ com.android.internal.os.zygoteinit$methodandargscaller.run(zygoteinit.java:1006) 05-14 00:30:56.640: e/androidruntime(29568):    @ com.android.internal.os.zygoteinit.main(zygoteinit.java:773) 05-14 00:30:56.640: e/androidruntime(29568):    @ dalvik.system.nativestart.main(native method) 

thanks helping me.

this common, had same trouble today. solved creating folder libs in project , adding amarinolibrary's jar folder instead of add external jar. after worked fine. hope you:).