Thread: Can't get a JToolBar, JMenuBar, and a JTabbedPane to all be visible at the same time.

It looks like the one you posted when you first started, yes.

How do I fix that?

In addition to that, apparently I don't know how to use getGraphics().

I tried it in another test program and called a method that drew something and called that method, passing it the result of the getGraphics(), which by the way I had to use the JFrame child class (the main program) to call that getGraphics() as the one for the JPanel I set as the content pane returned a null result), well anyway, it wouldn't draw anything. So I put it in a paint() method and suddenly it works.

But people have been able to use other methods besides paint() to draw things. I've seen it before. Don't recall quite what they did (otherwise I wouldn't be having this problem right now perhaps), but anyway, that appears to be the same thing going wrong in the above code that produces the window I just posted above.

The funny thing is, when I saw people do other methods that used Graphics, they often called repaint(), whatever that is, at the end of their method. But I think I tried that and it didn't know what the method was or something.

Maybe I misspelled something.

in the one above, not my test program, I have called paintComponent() for a JButton child class and it isn't drawing anything.

Perhaps I don't know what paintComponent() does, though I thought it drew on the component.

But how do people have different methods to draw something?

Also, paint seems to be being called repeatedly.

Also, another funny thing, I don't quite get how an abstract method from Graphics could actually draw something.

Also, it was someone else you told that getGraphics() was a bad idea, and I thought it was only for some certain situation.

I only used getGraphics() because I can't instantiate a Graphics object, though I have tried

DebugGraphics dbg = new DebugGraphics();

and then used it to call a method, but I kept getting a Null Pointer Exception.

getGraphics() wasn't throwing any compiler errors or run errors, unless I tried it with the JPanel, then it was as apparently the JPanel didn't have any graphics or something like that.

Anyway, as for how in the world could all of those abstract methods do something when called makes me wonder if JComponent or something defined those methods or something.

Or if the JFrame or whatever is calling the Graphics subclass DebugGraphics.

I mean, is paint() the only method to draw, besides paintComponent()?

However, I needed to call paint() method in the previous bit of code inside an ActionListener and don't know how to do it without getGraphics(), which won't draw it anyway.

I'll look at that link.

Got some things to work, but the image still isn't being drawn when I call getImage().

Also, how do I deal with the Null Pointer Exception?

import java.awt.event.*;
import java.awt.*;
import java.util.*;
import java.io.*;
import javax.swing.*;
import javax.swing.JOptionPane;
 
 
public class JavaPaintProgram extends JFrame implements MouseListener
{
 
private JPanel panel;
private JToolBar paintToolBar;
private JMenuBar menubar;
private JMenu file, help;
private JMenuItem save, importImage, help2, exit;
private JButton moreColors;
private JTabbedPane jtp;
private JColorChooser colorChooser;
private Color color;
private File f;
public JavaPaintProgram()
{
menubar = new JMenuBar();
file = new JMenu("File");
help = new JMenu("Help");
menubar.add(file);
menubar.add(help);
save = new JMenuItem("Save");
importImage = new JMenuItem("Item image from");
exit = new JMenuItem("Exit");
file.add(save);
file.addSeparator();
file.add(importImage);
file.addSeparator();
file.add(exit);
help2 = new JMenuItem("Help");
help.add(help2);
setJMenuBar(menubar);
paintToolBar = new JToolBar();
 
moreColors = new JButton("Select Color");
paintToolBar.add(moreColors);
paintToolBar.setBackground(Color.YELLOW);
JButton insertImageFromFile = new JButton("Upload Image From File");
 
paintToolBar.add(insertImageFromFile);
insertImageFromFile.setBackground(Color.GREEN);
 
panel = new JPanel();
System.out.println(panel.getDebugGraphicsOptions());
 
 
 
panel.add(paintToolBar);
setVisible(true);
panel.setVisible(true);
jtp = new JTabbedPane(JTabbedPane.TOP);
panel.add(jtp);
 PaintWindow atemp = new PaintWindow(new JPanel());
atemp.setVisible(false);
 
 
CircleJButton cjb = new CircleJButton("Draw a Circle");
 
paintToolBar.add(cjb);
 
jtp.addTab("A Tab", atemp);
 
panel.setLayout(new BoxLayout(panel, BoxLayout.X_AXIS));
JScrollPane jsp = new JScrollPane(panel, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED, JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
moreColors.addActionListener(new ActionListener() {
 
public void actionPerformed(ActionEvent e)
{
Color c = JColorChooser.showDialog(null, "Choose a color", Color.BLACK);
setColor(c);
 
}});
 
insertImageFromFile.addActionListener( new ActionListener() 
{
public void actionPerformed(ActionEvent e)
{
 
JFileChooser jfc = new JFileChooser();
 
jfc.setApproveButtonText("Upload Image");
 
 
jfc.showOpenDialog(null);
 
setFile(jfc.getSelectedFile());
 
 
repaint();
 
 
}});
 
  setContentPane(jsp);
 
}
 
 
public void setColor(Color color)
{
this.color = color;
}
 
public void setFile(File f)
{
 
this.f = f;
}
 
public File getFile()
{
return f;
}
 
 
 
public Color getColor()
{
return color;
}
 
 
public static void main(String[] args) throws ClassNotFoundException, InstantiationException, IllegalAccessException, UnsupportedLookAndFeelException
{
JavaPaintProgram paintProgram = new JavaPaintProgram();
// String cn = UIManager.getSystemLookAndFeelClassName();
           //  UIManager.setLookAndFeel(cn);
}
 
public void paint(Graphics g)
{
super.paint(g);
ImageIcon img  = new  ImageIcon(getFile().getName());
System.out.println(img);
 
 
 
 
 
 
System.out.println(img.getImage());
System.out.println(panel);
 g.drawImage( img.getImage(), 200, 200, Color.GREEN,this);
 
 
}
 
 
public void mouseClicked(MouseEvent e)
{
 
}
 
public void mouseEntered(MouseEvent e)
{
 
}
 
public void mouseExited(MouseEvent e)
{
 
}
 
public void mousePressed(MouseEvent e)
{
 
}
 
public void mouseReleased(MouseEvent e)
{
 
}
 
private class PaintWindow extends JScrollPane
{
public PaintWindow(Component panel)
{
super(panel, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED, JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
panel.setBackground(Color.WHITE);
panel.setVisible(true);
panel.setSize(3000, 3000);
panel.addMouseListener(JavaPaintProgram.this);
 
 
}
 
 
 
}
 
private class CircleJButton extends JButton
{
 
public CircleJButton(String title)
{
super(title);
setSize(100,100);
 
}
 
protected void paintComponent(Graphics g)
{
super.paintComponent(g);
g.setColor(Color.RED);
 
g.drawOval(5, 5, 22,22);
 
}
 
 
}
 
 
 
}

I know what's causing it. Paint apparently is called automatically by class.

Originally Posted by javapenguin

But how do people have different methods to draw something?

They override the paintComponent method of the component they want to draw on.

Also, paint seems to be being called repeatedly.

Swing calls the paint methods whenever it determines repainting may be necessary.

Also, another funny thing, I don't quite get how an abstract method from Graphics could actually draw something.

Via polymorphism. A Graphics subclass is provided that implements that method.

Also, it was someone else you told that getGraphics() was a bad idea, and I thought it was only for some certain situation.

I only used getGraphics() because I can't instantiate a Graphics object

You should not be trying to instantiate a Graphics object. Swing calls the paint methods and passes them a Graphics object that you can use when you override those methods.

I mean, is paint() the only method to draw, besides paintComponent()?

You will get nowhere without understanding how Swing GUI painting works. Read the link provided, and read this tutorial: Custom Painting, especially A Closer Look.

However, I needed to call paint() method in the previous bit of code inside an ActionListener and don't know how to do it without getGraphics(), which won't draw it anyway.

You clearly have no idea what you need to do.

I'll look at that link.

You need to understand what it says. Also, try following the examples in the tutorial that show you how painting works.