Looking for a simple way to change text in a JTextField with a button click

Question

I'm trying to get the action listener and button called French to change the text in the Output field to say Bonjour but many errors come up in the console when I click the button. I would like to do this in as few lines as possible.

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingConstants;
import javax.swing.event.ChangeEvent;

public class TranslatorFrame {

public static void main(String[] args) {

JFrame Words = new JFrame("Greetings Translator");
Words.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Did some research to find the line so the program 
//would appear in the center of the screen

Font Font1 = new Font("SansSerif",Font.BOLD,40);
JPanel WorkSpace = new JPanel();
JTextField Instructions = new JTextField("Enter \"Hello\" Here: ");
JTextField Input = new JTextField(); 
JPanel Center = new JPanel();
Center.setBackground(Color.lightGray);
Center.add(Instructions, BorderLayout.EAST);
Center.add(Input, BorderLayout.WEST);
JTextField Output = new JTextField("");
Output.setFont(Font1);
Output.setPreferredSize(new Dimension(195, 100));
JTextField Header = new JTextField();   
Header.setPreferredSize(new Dimension(195, 100));
Input.setPreferredSize(new Dimension(150,50));
Input.setFont(Font1);
Instructions.setPreferredSize(new Dimension(375,50));
Instructions.setBackground(Color.cyan);
//set the back ground color of my Instructions field so that it wouldn't
//look so gray and boring. There don't seem to be many preset colors to choose from. 
Instructions.setFont(Font1);
Instructions.setEditable(false);
JPanel ButtonsArea = new JPanel();
ButtonsArea.setBackground(Color.lightGray);
ButtonsArea.setPreferredSize(new Dimension(300,300));
JButton French = new JButton("French");
French.setPreferredSize(new Dimension(200, 150));
French.setFont(Font1);
French.addActionListener(new ChangeListener());

JButton German = new JButton("German");
German.setPreferredSize(new Dimension(200, 150));
German.setFont(Font1);
JButton Spanish = new JButton("Spanish");
Spanish.setPreferredSize(new Dimension(200, 150));
Spanish.setFont(Font1);
ButtonsArea.add(French, BorderLayout.EAST);
ButtonsArea.add(German, BorderLayout.CENTER);
ButtonsArea.add(Spanish, BorderLayout.WEST);
ButtonsArea.add(Output,BorderLayout.SOUTH);
//Tried many different things to get the buttons and textfields 
//to have space between them but nothing seems to work. 

//Header.setSize(100,100);
Header.setFont(Font1);
Header.setText("Welcome!");
Header.setEditable(false);
WorkSpace.setBackground(Color.LIGHT_GRAY);

class ChangeListener implements ActionListener {

    @Override
    public void actionPerformed(ActionEvent arg0) {

    if (arg0.getSource()==French);
    Output.setText("Bonjour!");
    }}
Words.pack();
Words.setSize(new Dimension(1000, 600));
Words.setLocationRelativeTo(null); 
WorkSpace.add(Header);
Words.add(WorkSpace, BorderLayout.NORTH);
Words.add(Center, BorderLayout.CENTER);
/*Words.add(Instructions, BorderLayout.CENTER);
Words.add(Input, BorderLayout.CENTER);*/
Words.add(ButtonsArea, BorderLayout.SOUTH);
//Words.add(Output, BorderLayout.SOUTH);
Words.setVisible(true);
    }

}

I assume that `French` and `Output` are outside of the context for `ChangeListener`, so they are undefined... — MadProgrammer, May 16 '15 at 01:27
1) Always copy/paste error and exception output! 2) Please learn common Java nomenclature (naming conventions - e.g. `EachWordUpperCaseClass`, `firstWordLowerCaseMethod()`, `firstWordLowerCaseAttribute` unless it is an `UPPER_CASE_CONSTANT`) and use it consistently. 3) Use a logical and consistent form of indenting code lines and blocks. The indentation is intended to make the flow of the code easier to follow! 4) See [Should I avoid the use of set(Preferred|Maximum|Minimum)Size methods in Java Swing?](http://stackoverflow.com/q/7229226/418556) (Yes.) — Andrew Thompson, May 16 '15 at 01:36
.. 5) `new Font("SansSerif",Font.BOLD,40)` would better be `new Font(Font.SANS_SERIF,Font.BOLD,40)` for compile time checking. — Andrew Thompson, May 16 '15 at 01:37

score 1 · Accepted Answer · answered May 16 '15 at 02:07

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;

public class TranslatorFrame {

    public static void main(String[] args) {

        JFrame Words = new JFrame("Greetings Translator");
        Words.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        // Did some research to find the line so the program
        // would appear in the center of the screen

        Font Font1 = new Font("SansSerif", Font.BOLD, 40);
        JPanel WorkSpace = new JPanel();
        JTextField Instructions = new JTextField("Enter \"Hello\" Here: ");
        JTextField Input = new JTextField();
        JPanel Center = new JPanel();
        Center.setBackground(Color.lightGray);
        Center.add(Instructions, BorderLayout.EAST);
        Center.add(Input, BorderLayout.WEST);
        final JTextField Output = new JTextField("");
        Output.setFont(Font1);
        Output.setPreferredSize(new Dimension(195, 100));
        JTextField Header = new JTextField();
        Header.setPreferredSize(new Dimension(195, 100));
        Input.setPreferredSize(new Dimension(150, 50));
        Input.setFont(Font1);
        Instructions.setPreferredSize(new Dimension(375, 50));
        Instructions.setBackground(Color.cyan);
        // set the back ground color of my Instructions field so that it
        // wouldn't
        // look so gray and boring. There don't seem to be many preset colors to
        // choose from.
        Instructions.setFont(Font1);
        Instructions.setEditable(false);
        JPanel ButtonsArea = new JPanel();
        ButtonsArea.setBackground(Color.lightGray);
        ButtonsArea.setPreferredSize(new Dimension(300, 300));
        final JButton French = new JButton("French");
        French.setPreferredSize(new Dimension(200, 150));
        French.setFont(Font1);
        French.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent arg0) {
                if (arg0.getSource() == French)
                    ;
                Output.setText("Bonjour!");

            }
        });

        JButton German = new JButton("German");
        German.setPreferredSize(new Dimension(200, 150));
        German.setFont(Font1);
        JButton Spanish = new JButton("Spanish");
        Spanish.setPreferredSize(new Dimension(200, 150));
        Spanish.setFont(Font1);
        ButtonsArea.add(French, BorderLayout.EAST);
        ButtonsArea.add(German, BorderLayout.CENTER);
        ButtonsArea.add(Spanish, BorderLayout.WEST);
        ButtonsArea.add(Output, BorderLayout.SOUTH);
        // Tried many different things to get the buttons and textfields
        // to have space between them but nothing seems to work.

        // Header.setSize(100,100);
        Header.setFont(Font1);
        Header.setText("Welcome!");
        Header.setEditable(false);
        WorkSpace.setBackground(Color.LIGHT_GRAY);

        Words.pack();
        Words.setSize(new Dimension(1000, 600));
        Words.setLocationRelativeTo(null);
        WorkSpace.add(Header);
        Words.add(WorkSpace, BorderLayout.NORTH);
        Words.add(Center, BorderLayout.CENTER);
        /*
         * Words.add(Instructions, BorderLayout.CENTER); Words.add(Input,
         * BorderLayout.CENTER);
         */
        Words.add(ButtonsArea, BorderLayout.SOUTH);
        // Words.add(Output, BorderLayout.SOUTH);
        Words.setVisible(true);
    }

}

Looking for a simple way to change text in a JTextField with a button click

1 Answers1