android - Why "OnClickListener" is not working -

I do not understand why this simple code is not working.
This code believes the color of the button is set to blue, all this is that I have just added a newly created project:

  last button btn = (button ) FindViewById (R.id.button1); Btn.setOnClickListener (New View.OnClickListener () {@Override Public Zero Click on (see V)} // click on btn.setTextColor (color.BLUE);}}};   
 Full code:  
  package com.example.b; Import android.graphics.color; Importroid.os.Bundle; Import android.support.v4.app.Fragment; Import android.support.v7.app.ActionBarActivity; Import android.view.LayoutInflater; Import android.view.Menu; Import android.view.MenuItem; Import android.view.View; Import android.view.ViewGroup; Import android.widget.Button; Public Class Main Activity ActionBarActivity (Creates the bundled saved instenstate) on Protected Zero {Super.Creative InstantState}; SetContentView (R.layout.activity_main); Find the last button BTN = (button) VVBIID (R.B. button 1); Btn.setOnClickListener (New View.OnClickListener () {@Override Public Zero Click on (see V)} // click on btn.setTextColor (color.BLUE);}}}; If (savedInstanceState == zero) {getSupportFragmentManager () BeginTransaction () .add (R.id.container, new placeholder fragment ()) .commit (); }} @ Override Public Boolean On Crate Option Menu (Menu Menu) {// Increase Menu; It adds the item to the Action Bar if it exists GetMenuInflater (). Fulao (R. menu menu, menu); Back true; } @ Override Public Boolean On Option Itam Select (menu item) {// Handle action bar item here clicks the action bar will automatically handle clicks on the home / up button automatically, so long as / when You specify a parental activity in AndroidManifest.xml. Int id = item.getItemId (); If (id == R.id.action_settings) {return true; } Return Super.Options item selected (item); } / ** * A placeholder piece containing a simple view. * / Public static class placeholder Fregment (public placeholder fragment) () {} @ See override public Crete View (Leautifltr Inflatr, View Group container, bundle saved Instensstet) {See Rutwu = Inflaiar Inflat (r. Leteft. Framentment_man, container, Falls); Return root view; }}}}    
 
 
 Most likely that the button is in the segment and there is no activity If so, take your search vibidibi and your satonclic code into your Playworldfragment.