java - How to make JFileChooser not appearing along with the form it belongs? -

based on tutorial have added jfilechooser in form , appears when form loaded first time along form. ideas on how fix that? here code:

/* * change template, choose tools | templates * , open template in editor. */ package nysemarketpick; import java.io.file; import java.io.ioexception; import javax.swing.jfilechooser; /** * * @author skiabox */ public class mainform extends javax.swing.jframe { /** * creates new form mainform */ public mainform() { initcomponents(); } /** * method called within constructor initialize form. * warning: not modify code. content of method * regenerated form editor. */ @suppresswarnings("unchecked") // <editor-fold defaultstate="collapsed" desc="generated code"> private void initcomponents() { mainpanel = new javax.swing.jpanel(); filechooser = new javax.swing.jfilechooser(); jmenubar1 = new javax.swing.jmenubar(); jmenu1 = new javax.swing.jmenu(); open = new javax.swing.jmenuitem(); exit = new javax.swing.jmenuitem(); jmenu2 = new javax.swing.jmenu(); jmenu3 = new javax.swing.jmenu(); jmenu4 = new javax.swing.jmenu(); setdefaultcloseoperation(javax.swing.windowconstants.exit_on_close); settitle("nyse stock pick"); setsize(new java.awt.dimension(1920, 1080)); org.jdesktop.layout.grouplayout mainpanellayout = new org.jdesktop.layout.grouplayout(mainpanel); mainpanel.setlayout(mainpanellayout); mainpanellayout.sethorizontalgroup( mainpanellayout.createparallelgroup(org.jdesktop.layout.grouplayout.leading) .add(0, 1082, short.max_value) ); mainpanellayout.setverticalgroup( mainpanellayout.createparallelgroup(org.jdesktop.layout.grouplayout.leading) .add(0, 621, short.max_value) ); jmenu1.settext("file"); open.settext("open"); open.addactionlistener(new java.awt.event.actionlistener() { public void actionperformed(java.awt.event.actionevent evt) { openactionperformed(evt); } }); jmenu1.add(open); exit.settext(" exit"); exit.addactionlistener(new java.awt.event.actionlistener() { public void actionperformed(java.awt.event.actionevent evt) { exitactionperformed(evt); } }); jmenu1.add(exit); jmenubar1.add(jmenu1); jmenu2.settext("options"); jmenubar1.add(jmenu2); jmenu3.settext("tools"); jmenubar1.add(jmenu3); jmenu4.settext("help"); jmenubar1.add(jmenu4); setjmenubar(jmenubar1); org.jdesktop.layout.grouplayout layout = new org.jdesktop.layout.grouplayout(getcontentpane()); getcontentpane().setlayout(layout); layout.sethorizontalgroup( layout.createparallelgroup(org.jdesktop.layout.grouplayout.leading) .add(mainpanel, org.jdesktop.layout.grouplayout.default_size, org.jdesktop.layout.grouplayout.default_size, short.max_value) .add(layout.createparallelgroup(org.jdesktop.layout.grouplayout.leading) .add(layout.createsequentialgroup() .add(0, 266, short.max_value) .add(filechooser, org.jdesktop.layout.grouplayout.preferred_size, org.jdesktop.layout.grouplayout.default_size, org.jdesktop.layout.grouplayout.preferred_size) .add(0, 266, short.max_value))) ); layout.setverticalgroup( layout.createparallelgroup(org.jdesktop.layout.grouplayout.leading) .add(layout.createsequentialgroup() .addcontainergap() .add(mainpanel, org.jdesktop.layout.grouplayout.preferred_size, org.jdesktop.layout.grouplayout.default_size, org.jdesktop.layout.grouplayout.preferred_size) .addcontainergap(43, short.max_value)) .add(layout.createparallelgroup(org.jdesktop.layout.grouplayout.leading) .add(layout.createsequentialgroup() .add(0, 135, short.max_value) .add(filechooser, org.jdesktop.layout.grouplayout.preferred_size, org.jdesktop.layout.grouplayout.default_size, org.jdesktop.layout.grouplayout.preferred_size) .add(0, 135, short.max_value))) ); pack(); }// </editor-fold> private void openactionperformed(java.awt.event.actionevent evt) { // todo add handling code here: int returnval = filechooser.showopendialog(this); if (returnval == jfilechooser.approve_option) { file file = filechooser.getselectedfile(); //what file pricevolumechart chart = new pricevolumechart(file.getname()); mainpanel = chart.mypanel; } else { system.out.println("file access cancelled user."); } } private void exitactionperformed(java.awt.event.actionevent evt) { // todo add handling code here: system.exit(0); } /** * @param args command line arguments */ public static void main(string args[]) { /* * set nimbus , feel */ //<editor-fold defaultstate="collapsed" desc=" , feel setting code (optional) "> /* * if nimbus (introduced in java se 6) not available, stay * default , feel. details see * http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html */ try { (javax.swing.uimanager.lookandfeelinfo info : javax.swing.uimanager.getinstalledlookandfeels()) { if ("nimbus".equals(info.getname())) { javax.swing.uimanager.setlookandfeel(info.getclassname()); break; } } } catch (classnotfoundexception ex) { java.util.logging.logger.getlogger(mainform.class.getname()).log(java.util.logging.level.severe, null, ex); } catch (instantiationexception ex) { java.util.logging.logger.getlogger(mainform.class.getname()).log(java.util.logging.level.severe, null, ex); } catch (illegalaccessexception ex) { java.util.logging.logger.getlogger(mainform.class.getname()).log(java.util.logging.level.severe, null, ex); } catch (javax.swing.unsupportedlookandfeelexception ex) { java.util.logging.logger.getlogger(mainform.class.getname()).log(java.util.logging.level.severe, null, ex); } //</editor-fold> /* * create , display form */ java.awt.eventqueue.invokelater(new runnable() { @override public void run() { new mainform().setvisible(true); } }); } // variables declaration - not modify private javax.swing.jmenuitem exit; private javax.swing.jmenuitem open; private javax.swing.jfilechooser filechooser; private javax.swing.jmenu jmenu1; private javax.swing.jmenu jmenu2; private javax.swing.jmenu jmenu3; private javax.swing.jmenu jmenu4; private javax.swing.jmenubar jmenubar1; private javax.swing.jpanel mainpanel; // end of variables declaration } 

much of code generated netbeans.

i managed fix problem adding jfilechooser other components node in navigator window of netabens (v7.1.2), instead of adding jform. maybe tutorial old , , may work in older netbeans versions.