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I am developing a gp calculator. How can i assign a value to selected item on the jcombobox. For example i created a jcombobox, and added A,B,C to it as its item, i want if A is selected let A be equals to 5 and multiplied by 2 and the result be pasted in a Jtextfield.

just like A = 5*2 and the result be pasted to a textfield.
I will be waiting for your reply please kindly help me out.
please don't mind my expression

What exactly do you want answers to?
How to assign values based on a selected item? Or how to append text to a JTextField?

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codeaddict: What exactly do you want answers to?
How to assign values based on a selected item? Or how to append text to a JTextField?

how to assign values to a selected item. like if the items are A,B,C. when the user selects A, i want A = 5 * 2;
then the result which is 10 be displayed on a jtextfield

xtianh: I am developing a gp calculator. How can i assign a value to selected item on the jcombobox. For example i created a jcombobox, and added A,B,C to it as its item, i want if A is selected let A be equals to 5 and multiplied by 2 and the result be pasted in a Jtextfield.

just like A = 5*2 and the result be pasted to a textfield.
I will be waiting for your reply please kindly help me out.
please don't mind my expression

create an event listener for the combox box, and if u are using an ide, in the itemStateChanged event, put

Switch (gradeComboBox.getSelectedIndex()){
Case 0:
JTextBoxResult.setText(String.valueOf(5 x 2));
break;
Case 1:
JTextBoxResult.setText(String.valueOf(4 x 2));
break;
Case 2:
JTextBoxResult.setText(String.valueOf(3 x 2));
break;
Case 3:
JTextBoxResult.setText(String.valueOf(2 x 2));
break;
Case 4:
JTextBoxResult.setText(String.valueOf(1 x 2));
break;
}

xtianh: how to assign values to a selected item. like if the items are A,B,C. when the user selects A, i want A = 5 * 2;
then the result which is 10 be displayed on a jtextfield

Something similar to this:

import javax.swing.JTextArea;
import javax.swing.JFrame;
import javax.swing.JComboBox;
import java.awt.event.*;
import java.awt.FlowLayout;
public class GPA extends JFrame implements ItemListener
{
    private JComboBox<String> combo;
    private JTextArea textArea;
    public GPA()
    {
        setLayout(new FlowLayout());
        String[] options = {"A", "B", "C", "", "E"};
        combo = new JComboBox<String>(options);
        add(combo);
        textArea = new JTextArea(2,15);
        combo.addItemListener(this);
        add(textArea);
        textArea.setText(10 + "";
        pack();
        setVisible(true);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
    public void itemStateChanged(ItemEvent e)
    {
        switch(combo.getSelectedIndex())
        {
            case 0:
                textArea.setText(10 + "";
                break;
            case 1:
                textArea.setText(8 + "";
                break;
            case 2:
                textArea.setText(6 + "";
                break;
            case 3:
                textArea.setText(4 + "";
                break;
            case 4:
                textArea.setText(2 + "";
                break;
            default:
                break;
        }
    }
    public static void main(String[] args)
    {
        GPA newV = new GPA();
    } 
}

Replace with D
Replace with )

thanks to u guys.
I will be posting my area of difficulty here please i would like you to always visit and render a helping hand

chykmoni: Visit W3Cschool.com

Not sure how u think or reason, But i thought u should remind you that commentin is not by force, W3schools for java? na wa oo