如何从Java中的另一个类访问comboBox

Question

comboBoxEnvIn Java is it possible to access a comboBox when it is sitting within a different class entirely?I want to use it as a whole and not just pass through it's values.

I have two classes - each has a GUI. I have my main.java (main) class and my ExportImportWindow.java

I am trying to access the comboBox that I use in my ExportImportWindow class called comboBoxEnv

Currently my code in my main class refers/uses the wrong comboBox called comboBox.

It's causing the information that is written to a file to be the incorrect information.

My code from main is this:

if (comboBox.getSelectedItem() == null ){

JOptionPane.showMessageDialog( null, "Please choose an ei");
}

else {

String env = comboBox.getSelectedItem().toString();

ExportImportWindow frm = new ExportImportWindow("Export",env,xmlFile , null, me); 

frm.setVisible( true );
}

I am unsure as to how I can get access to the correct comboBox which sits in the other class like so. I have already declared it at the top of my code as to attempt to access it within my main class.

public final JComboBox comboBoxEnv ;

public ExportImportWindow( final String mode, final String env,String FromFile,String ToFile, final Main main){

comboBoxEnv = new JComboBox();

//other code to populate comboBoxEnv
}

This is what I currently have after my last attempt did not work:

    ExportImportWindow exportImport = new ExportImportWindow(//not sure what to pass through);
    exportImport.comboBoxEnv; // trying to access the method the ComboBoxEnv sits in

I feel all the articles I look at are simply asking how to pass the values whether as I want to use the entire comboBox and not just it's values. Really appreciate any one who could share their knowledge on this. I did get access to it but it was only by creating it as a method which did not work.

Answer 1

You can define getter in your ImpexWindow (better) or just use the class' field because the field is public (not recommended way).

So in your ExportImportWindow you should keep a reference to the ImpexWindow where the combo box is defined and use the ImpexWindow's field