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JCreator not recognizing RBG Color in JFrame

I am trying to create an object of the class Color in awt to add it to the background of my JFrame ..but JCreator keep giving me this error message :
.java:23: error: cannot find symbol
getContentPane().setBackground(Color.color);
^
symbol: variable color
location: class Color
1 error
even when I am importing the Color class ... here is part of my code:
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import javax.swing.ImageIcon;
import java.awt.event.*;
import javax.swing.BorderFactory;
import java.awt.Font;
import java.awt.Color;
public class myframe extends JFrame implements ActionListener
{
public myframe()
{
setLayout(null);
Color color = new Color(135,206,235);
// Color skyblue = new Color((float)135,(float)206,(float)235);
getContentPane().setBackground(Color.color);
ImageIcon icon = new ImageIcon("horizntal logo.gif");
setIconImage(icon.getImage());

Calling a New Method from a Different Class in the Same Package

I am trying to create an application with several tabbed panes, and to keep the code manageable, I wanted to have the content for these panes in separate classes, in separate .java files.
I have 3 files currently
(i) TestLayout.java
package testlayout;
public class TestLayout
{
public static void main(String[] args)
{
MainFrame mainFrameObject = new MainFrame();
mainFrameObject.displayMainFrame();
}
}
(ii) MainFrame.java
package testlayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.GridLayout;
import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTabbedPane;
import javax.swing.SwingConstants;
public class MainFrame
{
JFrame masterFrame = new JFrame("JAVA 1.1");
JTabbedPane tabbedPane = new JTabbedPane();
public void displayMainFrame()
{
masterFrame.setSize(1000, 600);
masterFrame.setVisible(true);
masterFrame.setResizable(false);
masterFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
masterFrame.add(tabbedPane);
DisplayReadMe drmObj = new DisplayReadMe();
drmObj.showReadMe();
//showReadMe();
}
/*
public void showReadMe()
{
JPanel panelReadMe = new JPanel(new GridLayout(10,1,8,8));
panelReadMe.setBorder(BorderFactory.createEmptyBorder(4, 4, 4, 4));
tabbedPane.addTab("Read Me", null, panelReadMe, "First Tab");
String testreadMeTestMessage = "This is a test message";
JLabel testreadMeLabel = new JLabel(testreadMeTestMessage, SwingConstants.LEFT);
testreadMeLabel.setBorder(BorderFactory.createLineBorder(Color.orange,3));
panelReadMe.add(testreadMeLabel);
}
*/
}
and
(iii) DisplayReadMe.java
package testlayout;
import java.awt.Color;
import java.awt.GridLayout;
import javax.swing.BorderFactory;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingConstants;
public class DisplayReadMe extends MainFrame
{
public DisplayReadMe()
{
}
public void showReadMe()
{
System.out.println("method showReadMe begins");
JPanel panelReadMe = new JPanel(new GridLayout(10,1,8,8));
panelReadMe.setBorder(BorderFactory.createEmptyBorder(4, 4, 4, 4));
tabbedPane.addTab("Read Me", null, panelReadMe, "First Tab");
String testreadMeTestMessage = "This is a test message";
JLabel testreadMeLabel = new JLabel(testreadMeTestMessage, SwingConstants.LEFT);
testreadMeLabel.setBorder(BorderFactory.createLineBorder(Color.orange,3));
panelReadMe.add(testreadMeLabel);
System.out.println("method showReadMe ends");
}
}
My query is, when I uncomment the //showReadMe(); and showReadMe method in MainFrame, it works. The tab is added to the JFrame and the test message shows in the box.
But should the
DisplayReadMe drmObj = new DisplayReadMe();
drmObj.showReadMe();
code, not do the same thing? Am I not calling the showReadMe method from the DisplayReadMe class, akin to showReadMe().
I have tried revalidate, repaint and threading and nothing seems to call the method and show the tab and message ?
Any guidance would be gratefully appreciated
Many Thanks
PG

The method is actually working, but the tabbedPane instance in drmObj is different with respect to the JTabbedPane class member in MainFrame. Try to add tabbedPane as a parameter in showReadMe() and refer to that instance whenever adding elements. It should work.
public void showReadMe(JTabbedPane tabbedPane);
...
drmObj.showReadMe(this.tabbedPane);
Hope it helps!

you may not have duplicated method with same parameters, check if you have another showReadMe method who expects nothing as parameter.
if you make an overwrite of the showReadMe, remember that it will make showReadMe of the main class, then will make showReadMe inherited since it cannot go more up.
i donno if i explained it well at all.

JFrame doesn't show

I have the next problem: I'm calling a class from my Main, that have to show a JFrame. I can't even continue with my program because when I try to run it, the JFrame doesn't show.
I'm using Eclipse.
Main:
package System;
import java.util.Calendar;
import java.util.GregorianCalendar;
import java.awt.Menu;
import java.awt.*;
import javax.*;
import javax.swing.event.*;
import javax.swing.JButton;
import javax.swing.JFrame;
public class Main {
public static void main(String[] args) {
new Menu();
}
}
Second class:
package System;
import java.util.Calendar;
import java.util.GregorianCalendar;
import java.awt.*;
import javax.*;
import javax.swing.event.*;
import javax.swing.JButton;
import javax.swing.JFrame;
public class Menu {
private JFrame ventana = new JFrame("Sistema de Productos Químicos");
private JButton sup = new JButton("Supervisor");
private JButton oper = new JButton("Operario");
Menu()
{
ventana.setSize(500,500);
ventana.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
ventana.add(sup);
ventana.add(oper);
ventana.setVisible(true);
}
}
Thanks!

because your jframe class name is Menu and you have import
import java.awt.Menu;
this create a new awt menu instead of your Menu class which create a jframe
new Menu();
to fix this change the name of the Menu class to something different.
for instance
public class MyMenu { //

If you play around with System.out.println("Say something random"), which is something to do when your program is not working and it is not syntax error, you find out that the Main class is not even calling the Menu class, so that "cuts down" your area of search on what's srong, I have not found the problem, and will update the answer when I do.

"Selection does not contain a main Type" - Eclipse Run Error

I made a sample code to start one project just refactoring another one.
This the refactored one:
package com.sh.st;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.SwingConstants;
public class Main extends JFrame implements ActionListener {
/**
*
*/
JMenuBar bar;
JMenu file, register;
JMenuItem close, search;
ImageIcon figure1= new ImageIcon("C:/Users/Victor/Downloads/Untitled.jpg");
//ImageIcon figure2= new ImageIcon("C:/Victor Rocha/carroicon.jpg");
JLabel Ibimagem1,Ibimagem2;
/**
*
*/
public Main()
{
bar= new JMenuBar();
file= new JMenu("file");
register= new JMenu("register");
register.setMnemonic(KeyEvent.VK_R);
file.setMnemonic(KeyEvent.VK_F);
close= new JMenuItem("Close");
close.addActionListener(this);
search= new JMenuItem("Search");
search.addActionListener(this);
Ibimagem1= new JLabel(figure1, JLabel.CENTER);
Ibimagem1.setVerticalTextPosition(SwingConstants.CENTER);
bar.add(file);
bar.add(register);
file.add(close);
register.add(search);
//register.add(carro);
//register.add(cliente);
//register.add(funcionario);
getContentPane().add(Ibimagem1);
setSize(800,600);
setTitle("SHST");
setJMenuBar(bar);
setDefaultCloseOperation(0);
//setIconImage(figure2.getImage());
WindowListener J=new WindowAdapter(){
public void windowClosing(WindowEvent e){
System.exit(0);
}
};
addWindowListener(J);
}
public void actionPerformed(ActionEvent e){
if(e.getSource()==close){
System.exit(0);
}
if(e.getSource()==search){
Search s= new Search();
s.setVisible(true);
}
}
}
This is the original one:
package com.professordelphi.locadora;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.SwingConstants;
public class Principal extends JFrame implements ActionListener {
JMenuBar barra;
JMenu arquivo, cadastro;
JMenuItem fechar, cliente, funcionario, carro;
ImageIcon figura1= new ImageIcon("C:/Victor Rocha/carro.jpg");
ImageIcon figura2= new ImageIcon("C:/Victor Rocha/carroicon.jpg");
JLabel Ibimagem1,Ibimagem2;
public Principal()
{
barra= new JMenuBar();
arquivo= new JMenu("Arquivo");
cadastro= new JMenu("Cadastro");
cadastro.setMnemonic(KeyEvent.VK_C);
arquivo.setMnemonic(KeyEvent.VK_A);
fechar= new JMenuItem("Fechar");
fechar.addActionListener(this);
carro= new JMenuItem("Carro");
carro.addActionListener(this);
cliente= new JMenuItem("Cliente");
cliente.addActionListener(this);
funcionario= new JMenuItem("Funcionario");
funcionario.addActionListener(this);
Ibimagem1= new JLabel(figura1, JLabel.CENTER);
Ibimagem1.setVerticalTextPosition(SwingConstants.CENTER);
barra.add(arquivo);
barra.add(cadastro);
arquivo.add(fechar);
cadastro.add(carro);
cadastro.add(cliente);
cadastro.add(funcionario);
getContentPane().add(Ibimagem1);
setSize(800,600);
setTitle("Sistema de Cadastro");
setJMenuBar(barra);
setDefaultCloseOperation(0);
setIconImage(figura2.getImage());
WindowListener J=new WindowAdapter(){
public void windowClosing(WindowEvent e){
System.exit(0);
}
};
addWindowListener(J);
}
public void actionPerformed(ActionEvent e){
if(e.getSource()==fechar){
System.exit(0);
}
if(e.getSource()==carro){
Carro k = new Carro();
k.setVisible(true);
}
if(e.getSource()==cliente){
Cliente c = new Cliente();
c.setVisible(true);
}
if(e.getSource()==funcionario){
Funcionario f= new Funcionario();
f.setVisible(true);
}
}
}
The thing is, the original e building and the refactored is not. The error I receive from the refactored is that "Selection does not contain a main type". I saw a lot of posts regarding this theme but none of them solve my problem. Here is one little list of the things I've tried;
Source: Editor does not contain a main type
clean your workspace and rebuild your Project.
make sure you add your source folder in the project properties -> java build path -> source.
close your project and reopen it.
Trying to run as a Java Application with Eclipse, anyone has suggestions of what should I do?

You dont have a main function defined in the class. The main function is the function that will be called when you run the file.
Try adding
public static void main(String [] args)
{
}
and create and show an object of your JFrame in the main method.

Right click on your project ->Properties -> Java Build Path -> Source -> Add Folder
Now Select the src folder and click on OK

You should define a main method in your class (either one) with the following signature:
public static void main(String args[])
This method is the start point of program.
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.SwingConstants;
public class Main extends JFrame implements ActionListener {
public static void main(String args[]){
// from here the program execution starts
}
....
your other code
.....
}

The entry point for Java programs is the main method.
Does your class contain main method like below ?
public static void main(String[] args) {
//Code
}
If you do not have this, your program will not run.

Add image from URL in jPanel

I have a small problem, I have tried different solutions to add a image from URL in my jPanel, but I don't succeed. This is how my jPanel looks like:
import javax.swing.DefaultListModel;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import java.awt.Color;
import java.awt.Component;
import java.awt.FlowLayout;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Vector;
public class Hello extends JPanel{
JPanel panel = new BackgroundPanel();
JPanel HomeWindowPanel;
JLabel secondlbl = new JLabel("Hello");
public Hello () {
//I want to add a picture here from URL
}
}
I would really appreciate if somebody could show me how to do it.

Check out this sample code:
http://docs.oracle.com/javase/tutorial/displayCode.html?code=http://docs.oracle.com/javase/tutorial/uiswing/examples/components/LabelDemoProject/src/components/LabelDemo.java
Specifically the createImageIcon method.