java - Setting up android view library in project -

i trying use gauge view github in new project of mine.
sample application given library works perfect !

but when try include library new project (properties > buildpath > projects > (add library project)), put view in layout , try reference view in code throws classnotfoundexception

the following layout:

<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"     xmlns:tools="http://schemas.android.com/tools"     android:layout_width="match_parent"     android:layout_height="match_parent"     android:orientation="vertical"     tools:context=".mainactivity" >      <org.codeandmagic.android.gauge.gaugeview      android:id="@+id/gauge_view1"      android:layout_width="match_parent"      android:layout_height="0dp"      android:layout_weight="1" />   </linearlayout> 

this activity:

package com.example.guagetest;  import org.codeandmagic.android.gauge.gaugeview;  import android.os.bundle; import android.app.activity; import android.view.menu;  public class mainactivity extends activity {      private gaugeview gauge;      @override     protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.activity_main);         gauge = (gaugeview) findviewbyid(r.id.gauge_view1);         gauge.settargetvalue(10);     }      @override     public boolean oncreateoptionsmenu(menu menu) {         // inflate menu; adds items action bar if present.         getmenuinflater().inflate(r.menu.activity_main, menu);         return true;     } } 

can please tell me how import , use view in new project.

i've been trying more 4 hours set new project way setup in sample project on github page. have no luck.

someone please help.