Thread: My GUI will not show up.

I have written this program and I cannot get the GUI to show up. I cannot figure out what is wrong.
I appreciate any help guys.

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
 
public class TestScores extends JFrame
{
  private JLabel TestScoreLabel,TestWeightLabel;
  private JTextField TST1,TST2,TST3,TST4,TWT1,TWT2,TWT3,TWT4,TA;
  private JButton Calculate,Exit;
 
  private CalculateButtonHandler cbHandler;
  private ExitButtonHandler ebHandler;
 
  public void TestScoresProgram()
  {
    TestScoreLabel = new JLabel("Test Scores",SwingConstants.CENTER);
    TestWeightLabel = new JLabel("Test Weight",SwingConstants.CENTER);
 
    TST1 = new JTextField(10);
    TST2 = new JTextField(10);
    TST3 = new JTextField(10);
    TST4 = new JTextField(10);
    TWT1 = new JTextField(10);
    TWT2 = new JTextField(10);
    TWT3 = new JTextField(10);
    TWT4 = new JTextField(10);
    TA = new JTextField(20);
 
    Calculate = new JButton("Calculate");
    cbHandler = new CalculateButtonHandler();
    Calculate.addActionListener(cbHandler);
 
    Exit =  new JButton("Exit");
    ebHandler = new ExitButtonHandler();
    Exit.addActionListener(ebHandler);
 
    setTitle("Test Average Calculater");
 
    Container pane = getContentPane();
 
    pane.setLayout(new GridLayout(7,2));
 
    pane.add(TestScoreLabel);
    pane.add(TestWeightLabel);
    pane.add(TST1);
    pane.add(TWT1);
    pane.add(TST2);
    pane.add(TWT2);
    pane.add(TST3);
    pane.add(TWT3);
    pane.add(TST4);
    pane.add(TWT4);
    pane.add(TA);
    pane.add(Calculate);
    pane.add(Exit);
 
    pane.setSize(400,500);
    pane.setVisible(true);
  }
 
  private class CalculateButtonHandler implements ActionListener
  {
    public void actionPerformed(ActionEvent e)
    {
      double TS1,TS2,TS3,TS4;
      double TW1,TW2,TW3,TW4,Ave;
      TS1 = Double.parseDouble(TST1.getText());
      TS2 = Double.parseDouble(TST2.getText());
      TS3 = Double.parseDouble(TST3.getText());
      TS4 = Double.parseDouble(TST4.getText());
      TW1 = Double.parseDouble(TWT1.getText());
      TW2 = Double.parseDouble(TWT2.getText());
      TW3 = Double.parseDouble(TWT3.getText());
      TW4 = Double.parseDouble(TWT4.getText());
      Ave = (TS1 * TW1) + (TS2 * TW2) + (TS3 * TW3) + (TS4 * TW4);
      TA.setText("Your test average is " + Ave);
    }
  }
 
  private class ExitButtonHandler implements ActionListener
  {
    public void actionPerformed(ActionEvent e)
    {
      System.exit(0);
    }
  }
 
  public static void main(String[] args)
  {
    TestScores testObject = new TestScores();
  }
}

So annoying. Variable names and method names begin with lowercase letters. Aren't they teaching this anymore?

Your GUI is built in TestScoresProgram(). I'd like to know why, but I'd also like to know where that method is called. I don't know that that solves all of your problems, but it's a good start.

Originally Posted by GregBrannon

So annoying. Variable names and method names begin with lowercase letters. Aren't they teaching this anymore?

Your GUI is built in TestScoresProgram(). I'd like to know why, but I'd also like to know where that method is called. I don't know that that solves all of your problems, but it's a good start.

Sorry that's just how it is written in my book. And when I try to call the TestScoresProgram() it gives me an error that TestScoresProgram cannot be resolved to a type.

Show how you're calling it.

And if this is how the program is written in your book, including the name of the class not matching any call to instantiate it, the lack of a constructor, the variable names that don't follow Java's naming conventions, and the main() method that doesn't run the Swing GUI on the EDT, I recommend you throw this book away and get a new one.

With very minor corrections (most commented), this is how it should be done except for variable names. You can and should fix those. Still throw the book away.

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
 
// the filename in which this source code is saved should be
// TestScoresProgram.java
public class TestScoresProgram extends JFrame
{
    private JLabel TestScoreLabel, TestWeightLabel;
    private JTextField TST1, TST2, TST3, TST4, TWT1, TWT2, TWT3, TWT4, TA;
    private JButton Calculate, Exit;
 
    private CalculateButtonHandler cbHandler;
    private ExitButtonHandler ebHandler;
 
    // the default, no-argument constructor
    public TestScoresProgram()
    {
        TestScoreLabel = new JLabel( "Test Scores", SwingConstants.CENTER );
        TestWeightLabel = new JLabel( "Test Weight", SwingConstants.CENTER );
        TST1 = new JTextField( 10 );
        TST2 = new JTextField( 10 );
        TST3 = new JTextField( 10 );
        TST4 = new JTextField( 10 );
        TWT1 = new JTextField( 10 );
        TWT2 = new JTextField( 10 );
        TWT3 = new JTextField( 10 );
        TWT4 = new JTextField( 10 );
        TA = new JTextField( 20 );
        Calculate = new JButton( "Calculate" );
        cbHandler = new CalculateButtonHandler();
        Calculate.addActionListener( cbHandler );
        Exit =  new JButton( "Exit" );
        ebHandler = new ExitButtonHandler();
        Exit.addActionListener( ebHandler );
        setTitle( "Test Average Calculater" );
        Container pane = getContentPane();
        pane.setLayout( new GridLayout( 7, 2 ) );
        pane.add( TestScoreLabel );
        pane.add( TestWeightLabel );
        pane.add( TST1 );
        pane.add( TWT1 );
        pane.add( TST2 );
        pane.add( TWT2 );
        pane.add( TST3 );
        pane.add( TWT3 );
        pane.add( TST4 );
        pane.add( TWT4 );
        pane.add( TA );
        pane.add( Calculate );
        pane.add( Exit );
 
        // notice these methods are applied to the JFrame, not the
        // Container pane
        pack();
        setVisible( true );
 
    }
 
    private class CalculateButtonHandler implements ActionListener
    {
        public void actionPerformed( ActionEvent e )
        {
            double TS1, TS2, TS3, TS4;
            double TW1, TW2, TW3, TW4, Ave;
            TS1 = Double.parseDouble( TST1.getText() );
            TS2 = Double.parseDouble( TST2.getText() );
            TS3 = Double.parseDouble( TST3.getText() );
            TS4 = Double.parseDouble( TST4.getText() );
            TW1 = Double.parseDouble( TWT1.getText() );
            TW2 = Double.parseDouble( TWT2.getText() );
            TW3 = Double.parseDouble( TWT3.getText() );
            TW4 = Double.parseDouble( TWT4.getText() );
            Ave = ( TS1 * TW1 ) + ( TS2 * TW2 ) + ( TS3 * TW3 ) + ( TS4 * TW4 );
            TA.setText( "Your test average is " + Ave );
        }
    }
 
    private class ExitButtonHandler implements ActionListener
    {
        public void actionPerformed( ActionEvent e )
        {
            System.exit( 0 );
        }
    }
 
    // runs the GUI on the EDT
    public static void main( String[] args )
    {
        SwingUtilities.invokeLater( new Runnable()
        {
            public void run()
            {
                new TestScoresProgram();
            }
        } );
    }
}

I am calling it this way

public static void main(String[] args)
  {
    TestScoresProgram test = new TestScoresProgram();
  }

In case the update is not obvious, so my update to post #4.

And as for your latest post, of course you can't declare the variable test to be of type TestScoresProgram when TestScoresProgram doesn't exist as a class. It's a method, not a type. And why declare a variable 'test' at all? It's not used, so why bother? I would show you how it could be done with your current code, but I think it would be counter productive. Instead, your code should be modified as I've done above in post #4.