Changing an Activity in Android -

i'm learning android here, , java honest. i'm trying switch different activity via button click, however, keeps crashing. crashes when click button , go make switch. can please me figure i'm going wrong?

first activity:

package com.example.killacatoe;  import android.os.bundle; import android.app.activity; import android.view.*; import android.widget.*; import android.content.*;  public class tictactoe extends activity {//start tictacttoe class  //constants  //variables button mainbutton;  @override protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_tic_tac_toe);     mainbutton = (button) findviewbyid(r.id.bplaynow);     mainbutton.setonclicklistener(new view.onclicklistener(){          public void onclick(view v) {             // todo auto-generated method stub             intent = new intent(getapplicationcontext(), playermenu.class);             startactivity(i);         }        }); }  }//end tictactoe class 

activity i'm jumping to:

package com.example.killacatoe;  import android.os.bundle; import android.app.activity; import android.view.*; import android.widget.*;  public class playermenu extends activity {      button boneplayer, btwoplayer;      protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.player);         boneplayer = (button) findviewbyid(r.id.boneplayer);         boneplayer.setonclicklistener(new view.onclicklistener(){              public void onclick(view v) {                 // todo auto-generated method stub              }            });         btwoplayer = (button) findviewbyid(r.id.btwoplayer);         btwoplayer.setonclicklistener(new view.onclicklistener(){              public void onclick(view v) {                 // todo auto-generated method stub              }            });     } } 

here xml first activity:

<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"     android:background="#000000"     android:paddingbottom="@dimen/activity_vertical_margin"     android:paddingleft="@dimen/activity_horizontal_margin"     android:paddingright="@dimen/activity_horizontal_margin"     android:paddingtop="@dimen/activity_vertical_margin"     tools:context=".tictactoe" >      <textview         android:id="@+id/textview1"         android:layout_width="wrap_content"         android:layout_height="wrap_content"         android:layout_alignparenttop="true"         android:layout_centerhorizontal="true"         android:layout_margintop="30dp"         android:textsize="50dp"         android:text="welcome \ntic-tac-toe"         android:textcolor="#ffffff" />      <button         android:id="@+id/bplaynow"         android:layout_width="150dp"         android:layout_height="100dp"         android:layout_below="@+id/textview1"         android:layout_centerhorizontal="true"         android:layout_margintop="137dp"         android:textsize="34dp"         android:text="play now!" />      </relativelayout> 

xml second activity:

   <?xml version="1.0" encoding="utf-8"?>     <absolutelayout xmlns:android="http://schemas.android.com/apk/res/android"         android:layout_width="match_parent"         android:layout_height="match_parent"           android:background="#000000"     android:paddingbottom="@dimen/activity_vertical_margin"     android:paddingleft="@dimen/activity_horizontal_margin"     android:paddingright="@dimen/activity_horizontal_margin"     android:paddingtop="@dimen/activity_vertical_margin" >     />      <textview     android:id="@+id/textview2"     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:layout_margintop="30dp"     android:layout_x="78dp"     android:layout_y="30dp"     android:text="game mode"     android:textcolor="#ffffff"     android:textsize="50dp" />      <button     android:id="@+id/boneplayer"     android:layout_width="250dp"     android:layout_height="wrap_content"     android:layout_x="25dp"     android:layout_y="160dp"     android:text="single player"     android:textsize="25dp" />      <button     android:id="@+id/btwoplayer"     android:layout_width="250dp"     android:layout_height="wrap_content"     android:layout_x="25dp"     android:layout_y="220dp"     android:text="two player"     android:textsize="25dp" />      </absolutelayout> 

for starting new activity, necessary add in manifest file.

<application >     ...      <activity         android:name="com.example.killacatoe.playermenu" >     </activity>  </application> 

then in oncreate(), starting new activity when button pressed, can do:

 protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.player);     boneplayer = (button) findviewbyid(r.id.boneplayer);     boneplayer.setonclicklistener(new view.onclicklistener(){          public void onclick(view v) {               intent intent = new intent(tictactoe.this, playermenu.class);               startactivity(intent);                              }        }); }