CODEWITHSUNDEEP
javaswingcolorsjdialog
Joe
Joe

Reputation: 21

Add components to JDialog

When I run this, an empty title bar is displayed. I just want to be able to see the components and work from there, but nothing is displayed. The dialog is designed to allow the user to select a color by moving sliders, then return to color to the main page. 

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

public class ColourDialog extends JDialog
{
    String colorNames[] = {"Red: ", "Green: ", "Blue: "};
    Label labels[] = new Label[3];
    JSlider slider[]= new JSlider[3];
    Label lb;
    static ColourDialog d;

    public void ColourDialog()
    {
        setModal(true);
        Container c = getContentPane();
        c.setLayout(new BorderLayout());
        JPanel sliderPanel = new JPanel();
        sliderPanel.setLayout(new GridLayout(0, 1));

        for (int i = 0; i < slider.length;  i++)
        {
            labels[i] = new Label(colorNames[i] + 255);

            sliderPanel.add(labels[i]);
            slider[i] = new JSlider(SwingConstants.HORIZONTAL, 0, 255, 255);
            slider[i].setMinorTickSpacing(10);
            slider[i].setMajorTickSpacing(50);
            slider[i].setPaintTicks(true);
            slider[i].setPaintLabels(true);

            sliderPanel.add(slider[i]);
            //slider[i].addChangeListener(this);
        }

        lb = new Label("Colour");

        c.add(sliderPanel, BorderLayout.CENTER);
        c.add(lb, BorderLayout.SOUTH);

        setSize(500, 450);
        setLocation(200,200);
        setTitle("Colour Dialog");
    }

    public static Color showDialog()
    {
        if (d == null)
        d = new ColourDialog();

        d.show();

        //return new Color(red,green,blue);
        return new Color(0,0,0);
    }

    public static void main(String args[])
    {
        ColourDialog.showDialog();
    }
}

Upvotes: 1

Views: 2110

Answers (3)

Java42
Java42

Reputation: 7716

You never call the method ColorDialog(). This is a good spot to mention "start methods with a lower case letter). To fix you code:

Change:

    d = new ColourDialog();

To:

    d = new ColourDialog(); 
    d.ColourDialog();

Upvotes: 0

mKorbel
mKorbel

Reputation: 109823

I think that you have look at JColorChooser, this JComponent can returns selected Color

there I can't fout out correct definitions and initializations for JSlider

EDIT

there are lots of mistakes starting with extends JDialog end with public static Color showDialog(), that returns empty container typos with initializations for ColourDialog()

enter image description here

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

public class ColourDialog {

    private JDialog dialog = new JDialog();
    private String colorNames[] = {"Red: ", "Green: ", "Blue: "};
    private Label labels[] = new Label[3];
    private JSlider slider[] = new JSlider[3];
    private Label lb;

    public ColourDialog() {
        JPanel sliderPanel = new JPanel();
        sliderPanel.setLayout(new GridLayout(0, 1));
        for (int i = 0; i < slider.length; i++) {
            labels[i] = new Label(colorNames[i] + 255);
            sliderPanel.add(labels[i]);
            slider[i] = new JSlider(SwingConstants.HORIZONTAL, 0, 255, 255);
            slider[i].setMinorTickSpacing(10);
            slider[i].setMajorTickSpacing(50);
            slider[i].setPaintTicks(true);
            slider[i].setPaintLabels(true);
            sliderPanel.add(slider[i]);
        }
        lb = new Label("Colour");
        dialog.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
        dialog.setModal(true);
        dialog.add(sliderPanel, BorderLayout.CENTER);
        dialog.add(lb, BorderLayout.SOUTH);
        dialog.pack();
        dialog.setLocation(200, 200);
        dialog.setTitle("Colour Dialog");
        dialog.setVisible(true);
    }

    public static void main(String args[]) {
        EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                ColourDialog colourDialog = new ColourDialog();
            }
        });
    }
}

Upvotes: 2

Shawn Shroyer
Shawn Shroyer

Reputation: 923

I think it might be because you say "public void ColourDialog()" this is an invalid constructor. Try getting rid of the "void" and try again.

Upvotes: 1

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