Question

I’ve looked at the other examples on here but the revalidate() or repaint() after I create all of my components. I’ve also tried the this.setVisible(this); and that didn’t work. I’ve tried creating my components in a createGUI() method and running that from the init() method within a try/catch statement.

EDIT
I tried all of your examples, as you can see in the comments. But from what everyone has said why does this now work?

package basic;

import java.awt.*;
//import java.applet.*;
import java.applet.Applet;
import javax.swing.*;
import java.awt.event.*;

public class Shapes extends Applet implements ActionListener
{
JButton rectBtn = new JButton("Rectangle");
JButton circBtn = new JButton("Circle");
JLabel rectLbl = new JLabel("Rectangle"), circLbl = new JLabel("Circle");
JLabel widthLbl = new JLabel("Width"), heightLbl = new JLabel("Height");
JTextField widthTF = new JTextField(6), heightTF = new JTextField(6), colorTF;

boolean rectOn;
boolean circOn;
int x,y, width, height;
String xcord, ycord, widthSize, heightSize;

public void init()
{   

    JPanel TotalGUI = new JPanel(new GridLayout(2,0));
    TotalGUI.add(rectLbl);      TotalGUI.add(rectBtn);
        rectBtn.addActionListener(this);
    TotalGUI.add(circLbl);      TotalGUI.add(circBtn);
        circBtn.addActionListener(this);
    TotalGUI.add(widthLbl);     TotalGUI.add(widthTF);
    TotalGUI.add(heightLbl);    TotalGUI.add(heightTF);
    add(TotalGUI, BorderLayout.WEST);
    //this.setVisible(true);
    TotalGUI.repaint();
    //pack();
}


//@Override
public void paintComponent(Graphics g)
{
    //super.paintComponent(g);
    //Graphics g2 = getGraphics();

    if(rectOn)//if Rectangle has been pressed
    {
        g.drawRect(x,y, width,height);
    }
    if(circOn)//if Circle has been pressed
    {
        g.drawOval(x,y, width, height);
    }
}

public void actionPerformed(ActionEvent e)
{
    if(e.getSource() == rectBtn)
    {
        rectOn = true;
    }
    if(e.getSource() == circBtn)
    {
        circOn = true;
    }
    //Reads coordinates and sizes as Strings and converts to integers
    try{
        widthSize = widthTF.getText();
        width = Integer.parseInt(widthSize);    
        heightSize = heightTF.getText();
        height = Integer.parseInt(heightSize);
    }
    catch(Exception err)    { JOptionPane.showMessageDialog(null, "Enter a number!");   }
    repaint();
}

}

Thank you for your help!

Answer 1

You should call repaint() on TotalGUI.

The reason your gui refreshes after resize, is that resize automatically calls repaint() for you. However, if you want you gui changes to appear instantly, you should call repaint();

A preferred approach, however, is to use in your totalGUI’s paint(Graphics g)/paintComponent(Graphics g) method/s:

super.paintComponent(g);

as described by these posts:

JPanel repaint issue

http://www.sitepoint.com/forums/showthread.php?273522-super.paintComponent()