Java , GUI application, Read text from a aTextField, display on a label

Rio Hondo College
CIT 136 Java Programming
Initialize a textfield:
JTextField tf = new JTextField(20);

Retrieve value from a textfield,

Convert a String to a number

// population is a string retrieved from a html file

Covert numbers to a string
int i;
double d;
Set Text on a label
JLabel label_2 = new JLabel();

Declare a static variable as a global variable to accumulate total amount
private static double total =0;

professor Liu