I need to do an buy form

Question

i have a problem, i'we made an form with one combo box , one text field and one text area where all the info is displayed. In the combo box there are 4 positions:Item 1 , Item 2, Item 3, Item 4. the user selects its item then types in the text field the amount of the item he wants, and in the textarea all this is displayed. this work but only with one Item. I mean, if i chose item 1 then select the amount of it it counts only this, and i want for example to add two Item 2's , and 3 Item 4's and to add everything up to make an over all price...
i need something that counts the price every time the button is pressed
sorry for my poor english
    private void jButton4ActionPerformed(java.awt.event.ActionEvent evt) {                                        
int selInd =jComboBox1.getSelectedIndex();
Object obj=jComboBox1.getSelectedItem();
String textIlosc= jTextField6.getText();
int liczba = Integer.parseInt(textIlosc);
double suma1=0.0;
double suma2=0.0;
double suma3=0.0;
double suma4=0.0;
double cena1=12.34;
double cena2=23.78;
double cena3=56.32;
double cena4=23.43;
if(obj.equals("Item 1")){
    suma1=cena1*liczba;
    ban1.deposit(suma1);
if(obj.equals("Item 2")){
    suma1=cena2*liczba;
    ban1.deposit(suma2);
cena=suma1+suma2;
arr1.insertP(obj , textIlosc , selInd ,cena );
// TODO add your handling code here:

Answer 1

You are setting the value of suma1,suma2....to Zero inside the method. What happens is ,it is initialised each time whenver the combo box is changed.
Do the initialisation outside the method. It will work fine.
Hope it helps.
thanks