1   // MainActivity.java

 2   // Calculates a bill total based on a tip percentage

 3   package com.deitel.tipcalculator;

 4

 5   import android.os.Bundle; // for saving state information

 6   import android.support.v7.app.AppCompatActivity; // base class

 7   import android.text.Editable; // for EditText event handling

 8   import android.text.TextWatcher; // EditText listener

 9   import android.widget.EditText; // for bill amount input

10   import android.widget.SeekBar; // for changing the tip percentage

11   import android.widget.SeekBar.OnSeekBarChangeListener; // SeekBar listener

12   import android.widget.TextView; // for displaying text

13

14   import java.text.NumberFormat; // for currency formatting

15