Q:

How to switch text view from one thing to the next when a button is clicked - Android

Below is my main activity file.  I am stuck with the bottom area (commented out).  I want to make it so that when I hit button b1, the text changes from what it is for default.  So say it says "hello" by default, I want to switch the text to something like "how are you" when you press button b1.  I have tried many things, but I always get errors.  Can someone help me?     
package com.wdmc85.donottouch;

import android.app. Activity;
import android.os. Bundle;
import android.view. View;
import android.view. View. OnClickListener;
import android.widget. Button;
import android.widget. TextView;

public class DoNotTouchActivity extends Activity 
implements OnClickListener {
/** Called when the activity is first created. */ 
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    Button b1 = (Button) this.findViewById(R.id.b1);
    b1.setOnClickListener(this);

}

@Override
public void onClick(View v) 
{
    switch(v.getId())
    {
    case R.id.b1:
        //WHAT DO I PUT IN HERE??  I WANT IT SO WHEN YOU HIT BUTTON B1, THE 
        //TEXT CHANGES FROM WHAT IT IS FOR DEFAULT.  SO SAY IT SAYS "HELLO"
        //AS DEFAULT, HOW DO I MAKE IT SO WHEN YOU PRESS BUTTON B1 THE TEXT
        //CHANGES FROM "HELLO" TO "HOW ARE YOU?"  I HAVE TRIED ALL SORTS OF
        //THINGS BUT NOTHING HAS WORKED
    break;
    }

}

}

A:

if want to change text   of the button itself 
 switch(v.getId())
        {
        case R.id.b1:
           Button b1 = (Button) v;
           b1.setText("HOW ARE YOU?"); 

        break;
        }

if want to change text  of the any other Textview 
 switch(v.getId())
        {
        case R.id.b1:
           TextView tv = (TextView ) this.findViewById(R.id.<tvid>);
           tv .setText("HOW ARE YOU?"); 

        break;
        }

