How to separate events fired from multiple JComboBox instances

Question

Hi everybody,
I have built a form with 2 JComboBox instances: each for separated options.
String[] items = {"Red", "Blue"};
        JComboBox comboBox1 = new JComboBox(items); // For water color
        JComboBox comboBox2 = new JComboBox(items); // For mountain color
        comboBox1.addActionListener(aListener);
        comboBox2.addActionListener(aListener);
        contentArea.add(comboBox1);
        contentArea.add(comboBox2);How can I distinguish which event is fired from comboBox1 and which event comes from comboBox2. I tried to implement actionPerformed method as follows:
public void actionPerformed(ActionEvent event) {
        Object eventSource = event.getSource();
        if (eventSource instanceof JComboBox) {
            JComboBox cb = (JComboBox)event.getSource();           
            System.out.println("From JCom "+cb);
            if (cb == comboBox1) {
                System.out.println("From comboBox1");
    }but it does not work. Java Compiler said: cannot find symbol comboBox1.
How can I resolve this problem?
Thanks in advance

Answer 1

Move the declarations for the comboboxes into class scope so they can be seen from within the "actionPerformed" method.
class SomeClass
    // instance variable declarations
    // these variables have class scope
    JComboBox comboBox1;
    JComboBox comboBox2;
    void aMethod()
        String[] items = {"Red", "Blue"};
        comboBox1 = new JComboBox(items); // For water color
        comboBox2 = new JComboBox(items); // For mountain color
    }Or you could use the "getActionCommand" and "setActionCommand" (JComboBox) methods to send along a string with the event.
Another option is to use the Component methods "setName" and "getName" to identify the sender of the event. Or you could use the JComponent "putClientProperty" and "getClientProperty" methods.