Problem - inner classes

[igorsivec]

Problem – Inner Classes

I have to collect values from JTextField(numbers) on a press of a button. Because JButtons addActionListener is a local inner class I would have to declare variables in a outer class “final”. This would not be OK because I want to change the value of JtextField. Is there any way to solve this problem – maybe with different design of a program or something else – I don't know – anything? Here is the code.



import javax.swing.*;
import javax.swing.border.*;
import java.awt.*;
import java.awt.event.*;


public class NewEmpty extends JDialog{
public NewEmpty( JFrame frame ) {
super( frame, true );
setSize( 700, 700 );

int Z1;

// Creates a panel to hold all components
JPanel panel = new JPanel( new BorderLayout() );
panel.setLayout( new GridBagLayout() );

// give the panel a border gap of 5 pixels
panel.setBorder( new EmptyBorder( new Insets( 5, 5, 5, 5 ) ) );
getContentPane().add( BorderLayout.CENTER, panel );
GridBagConstraints c = new GridBagConstraints();

// Define preferred sizes for input fields
Dimension shortField = new Dimension( 40, 20 );

// Spacing between label and field
EmptyBorder border = new EmptyBorder( new Insets( 0, 0, 0, 10 ) );

// add space around all components to avoid clutter
c.insets = new Insets( 2, 2, 2, 2 );

// anchor all components WEST
c.anchor = GridBagConstraints.WEST;

JLabel lbl1 = new JLabel( "Enter Number:" );
lbl1.setBorder( border ); // add some space to the right
panel.add( lbl1, c );
JTextField txt1 = new JTextField();
txt1.setPreferredSize( shortField );
c.gridx = 1;
c.weightx = 1.0; // use all available horizontal space
c.gridwidth = 3; // spans across 3 columns
c.fill = GridBagConstraints.HORIZONTAL; // fills the 3 columns
panel.add( txt1, c );



JButton submitBtn = new JButton( "Submit" );
c.gridx = 4;
c.gridy = 0;
c.gridwidth = 1;
c.fill = GridBagConstraints.HORIZONTAL;
panel.add( submitBtn, c );

submitBtn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ev) {

Z1 = Integer.parseInt(txt1.getText());
}

});
WindowListener wndCloser = new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
};
addWindowListener( wndCloser );

setVisible( true );
}
public static void main( String[] args ) {
new NewEmpty( new JFrame() );
}
}


TIA

[Joe Beam]

You can make JTextField final...and still change it's contents. All the final modifier does is not let you do this more than once...

jtField = new JTextField()

you can still change the text and stuff. It just has to be final to be used in an anonymous class.

[igorsivec]

I need to change JTextField more than once!

[Joe Beam]

I don't see where you are changing txt1 reference but if you really need to then don't use an anonymous class.