layout inflater - How to set and reuse source code on android -

i'm having trouble on developing android apps. want reuse section many other activities. , found "layout inflater". can use that.

<relativelayout 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"     tools:context=".mainactivity" >      <!-- header start -->     <relativelayout         android:id="@+id/header"         android:layout_width="match_parent"         android:layout_height="wrap_content"         android:layout_alignparenttop="true"         android:padding="5dp"         android:background="#fff8f8ff">          <!-- menu button -->         <button              android:id="@+id/menubtn"              android:layout_width="40dp"              android:layout_height="30dp"              android:layout_marginleft="10dp"              android:background="@drawable/menubtn"/>          <!-- logo / return main page -->         <button              android:id="@+id/logobtn"             android:layout_width="30dp"             android:layout_height="30dp"             android:layout_centerhorizontal="true"             android:layout_centervertical="true"             android:background="@drawable/ic_launcher"/>          <!-- login btn -->         <button             android:id="@+id/loginbtn"             android:layout_width="wrap_content"             android:layout_height="wrap_content"             android:layout_alignbottom="@id/logobtn"             android:layout_alignparentright="true"             android:layout_centervertical="true"             android:layout_marginright="10dp"             android:background="#00ffffff"             android:text="login"             android:textsize="20dp" />      </relativelayout>     <!-- end of header -->  </relativelayout> 

but, now! having problem next step. how set , reuse activity button listener , that.

    // header button listener     button menubtn = (button)findviewbyid(r.id.menubtn);     button logobtn = (button)findviewbyid(r.id.logobtn);     button loginbtn = (button)findviewbyid(r.id.loginbtn);      menubtn.setonclicklistener(new onclicklistener(){         public void onclick(view v){             toast.maketext(getbasecontext(), "menu", toast.length_short).show();         }     });      logobtn.setonclicklistener(new onclicklistener(){         public void onclick(view v){             toast.maketext(getbasecontext(), "logo", toast.length_short).show();         }     });      loginbtn.setonclicklistener(new onclicklistener(){         public void onclick(view v){             toast.maketext(getbasecontext(), "login", toast.length_short).show();         }     });     // end of header button  

i want reuse section other activities. , trying import system but, not yet.

shortly, want reuse source code(listener , xml). how can that?

public class youractivity extends activity implements button.onclicklistener{     protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_main);             menubtn.setonclicklistener(this);             logobtn.setonclicklistener(this);             loginbtn.setonclicklistener(this);  }  public void onclick(view v) {    if(menubtn == v)  {       showmytoast("menu");    }else if(logobtn == v){       showmytoast("logo");   }else if(loginbtn == v){       showmytoast("login");   }  }   private void showmytoast(string str){     toast.maketext(this, str, toast.length_short).show(); }  }