java - Is there a better way to connect two JPanels? -

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netbeans project , source code of minimal example

is there better way connect jframe jpanel class other making fields of jpanel public?

i writing program there going option button, when button pressed custom joptionpane.showoptiondialog brought jpanel inside hold specific options user wants.

when user presses joptionpane.ok_option button program closes optiondialog jpanel inside , returns jframe. need whatever inputted in jpanel used in jframe class. did making text fields of jpanel public feel cheap way of doing since netbeans not let me unless opened source in notepad.

also totally ok if joptionpane.ok_option saving fields of jpanel in file , separately retrieve them in jframe class.

so there better way this?

jframe action listener:

private void gosettingsactionperformed(java.awt.event.actionevent evt) {                                                    settings settings = new settings();         int result = joptionpane.showoptiondialog(null,                 settings,                 "settings",                 joptionpane.ok_cancel_option,                 joptionpane.information_message,                 null,                 new string[]{"save", "cancel"},                 "default");         if (result == joptionpane.ok_option) {             username = settings.jtextfield1.gettext();             usernameinputedlabel.settext(username);         }     }

your question specific example of general question: how 2 objects communicate?

  • your consideration of using public field know wrong.
  • you mention saving data file, isn't over-kill, , won't add needless time , resource overhead when simpler solution available?
  • better use same technique you'd use if not swing gui: public methods including getter , setter methods if need be.

e.g.,

private void gosettingsactionperformed(java.awt.event.actionevent evt) {                                                settings settings = new settings();     int result = joptionpane.showoptiondialog(null,             settings,             "settings",             joptionpane.ok_cancel_option,             joptionpane.information_message,             null,             new string[]{"save", "cancel"},             "default");     if (result == joptionpane.ok_option) {          // **** give settings class method:         username = settings.getusername();          usernameinputedlabel.settext(username);     } }

edit
state in comment:

i have used getters , setters books i've read , forums frequent know general consensus having getters , setters worse public fields.

sorry, that's hogwash. please consider code vs. code. in code above, suggest givng settings method, like:

// in declarations: // don't name jtextfield1 private jtextfield usernamefield = new jtextfield();  // public getter method public string getusername() {    return jtextfield1.gettext(); // should named usernamefield }

whereas suggestion make jtextfield public, exposing comers. riskier? allow calling code change state of settings object without knowing it?


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