swing - Java - ItemListener not listening to my components? -


i took segment of program , put code here. basically issue item listener method isnt being called. here if user selects right answer , presses "submit" actionlistener method tell him/her if got answer right.

static boolean answer = false; // returns true if user got question right  public void quizpanel() {     quizpanel = new jpanel();     quizpanel.setlayout(null); // default layout      jlabel label = new jlabel( "true/false- java object orientated?");     label.setbounds(10, 50, 400, 20);     quizpanel.add(label);      option1 = new jcheckbox("true");      option1.setselected(false);     option1.setbounds(10, 70, 120, 40);                              quizpanel.add(option1);     option1.additemlistener(this); // adds item listener      option2 = new jcheckbox("false");     option2.setselected(false);     option2.setbounds(40, 70, 120, 40);     quizpanel.add(option2);     option2.additemlistener(this);      ///////////////////////////////////////      jbutton submit = new jbutton("submit answer:");     submit.setbounds(10, 100, 150, 20);     quizpanel.add(submit);      submit.addactionlistener(new actionlistener() { // action listener               public void actionperformed(actionevent evt2) {             system.out.println ("your answer " + answer); // got right?         }     }); }  public void itemstatechanged1(itemevent e1) {      object source = e.getitemselectable();               if (source == option1) {          answer = true;     } else {         //nothing- stays false     }        }

nothing happens , doesn't tell user if he/she got right/wrong.

quizpanel = new jpanel();

use standard java naming conventions. variable names should not start upper case character:

quizpanel.setlayout(null); ... label.setbounds(10, 50, 400, 20);

don't use null layout , setbounds(). swing designed used layout manager.

public void itemstatechanged1(itemevent e1) throws ioexception

i don't know how code compiles. implementing wrong method. also, why itemlistener throw ioexception?

too many little mistakes guess doing wrong. post proper sscce.


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