ok so i have the following code(it probably is really sloppy but i'll clean it up when i get it working.)

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

public class lab4 extends JFrame {
	private JTextArea jta;
	private Histogram histogram = new Histogram();

	public lab4()
	{
		// Store text area in a scroll pane
		JScrollPane scrollPane = new JScrollPane(jta = new JTextArea());
		jta.setWrapStyleWord(true);
		jta.setLineWrap(true);
		jta.setPreferredSize(new Dimension(800,300));
		jta.setLayout(new GridLayout(2,1,1,1));




		add(scrollPane);

		jta.addKeyListener(new KeyAdapter() {
				  /** Handle the button action */
				  public void KeyPressed(KeyEvent e) {
		   			 // Count the letters in the text area
		   			 int[] count = countLetters();

					// Set the letter count to histogram for display
		   			 histogram.showHistogram(count);


				  }
			});


		jta.add(histogram);
	}



	private int[] countLetters()
	{
		// Count for 26 letters
		int[] count = new int[26];

		// Get contents from the text area
		String text = jta.getText();

		text = text.toUpperCase();

		// Count occurrence of each letter (case insensitive)
		for (int i = 0; i < text.length(); i++)
		{
		  char character = text.charAt(i);

		  if ((character >= 'A') && (character <= 'Z'))
		  {
			count[(int)character - 65]++; // The ASCII for 'A' is 65
		  }
		  }
		  return count; // Return the count array
	  }



	public static void main(String[] args) {
	   lab4 frame = new lab4();
	   frame.setLocationRelativeTo(null); // Center the frame
	   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	   frame.setTitle("lab4");
	   frame.setSize(800,600);
	   frame.pack();
	   frame.setVisible(true);

	}
}

here is the histogram code:

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

public class Histogram extends JPanel {
  // Count the occurrence of 26 letters
  private int[] count;

  /** Set the count and display histogram */
  public void showHistogram(int[] count) {
	this.count = count;
	repaint();
  }

  /** Paint the histogram */
  protected void paintComponent(Graphics g) {
	if (count == null) return; // No display if count is null

	super.paintComponent(g);

	// Find the panel size and bar width and interval dynamically
	int width = getWidth();
	int height = getHeight();
	int interval = (width - 40) / count.length;
	int individualWidth = (int)(((width - 40) / 24) * 0.60);

	// Find the maximum count. The maximum count has the highest bar
	int maxCount = 0;
	for (int i = 0; i < count.length; i++) {
	  if (maxCount < count[i])
		maxCount = count[i];
	}

	// x is the start position for the first bar in the histogram
	int x = 30;

	// Draw a horizontal base line
	g.drawLine(10, height - 45, width - 10, height - 45);
	for (int i = 0; i < count.length; i++) {
	  // Find the bar height
	  int barHeight =
		(int)(((double)count[i] / (double)maxCount) * (height - 55));

	  // Display a bar (i.e. rectangle)
	  g.drawRect(x, height - 45 - barHeight, individualWidth,
		barHeight);

	  // Display a letter under the base line
	  g.drawString((char)(65 + i) + "", x, height - 30);

	  // Move x for displaying the next character
	  x += interval;
	}
  }

  /** Override getPreferredSize */
  public Dimension getPreferredSize() {
	return new Dimension(300, 300);
  }
}

what this is sapposed to do is display an input field in the bottom which a user inputs random letters and in the top half it displays in bar graph form the amount of A's-Z's the user inputed

This post has been edited by rgfirefly24: 18 April 2008 - 09:51 AM

I don't say that it is not possible but I have never seen a JTextArea with a awt.Layout

Assuming it is possible (the compiler does not complain and there are no run time error)

OK now you have a JTextArea with a GridLayout on 2 rows ?

You have add(histogram) and what else ? What goes on the second row.

How does a JTextArea, with a layout of 2 rows, knows where to add (in which row to add) the characters typed ?

This seems compilcated to me but again I might be completly wrong.

Why don't you simply set your JFrame with a GridLayout(2,1,1,1);
- add to the frame the JTextArea in its JScrollPane
- add the histogram

Then you will have your JTextArea in first row and your histogram in the second row.

I mean I don't see any sens of adding the JPanel where you draw into a JTextArea.

Also what you want is a KeyListener not a KeyAdapter
you will have to implement the 3 methods:

		jta.addKeyListener(new KeyListener() {
				  /** Handle the button action */
				  public void keyPressed(KeyEvent e) {
						// Count the letters in the text area
						int[] count = countLetters();

					// Set the letter count to histogram for display
						histogram.showHistogram(count);
				  }

	public void keyReleased(KeyEvent e) {
	}
	public void keyTyped(KeyEvent e) {				
	}
			});

and the name of the method is keyPressed not KeyPressed (capital K).

This kind of work

    public lab4()
    {
    	setLayout(new GridLayout(2,1,1,1));
        // Store text area in a scroll pane
    	jta = new JTextArea();
        JScrollPane scrollPane = new JScrollPane(jta);
        jta.setWrapStyleWord(true);
        jta.setLineWrap(true);
        jta.setPreferredSize(new Dimension(800,300));

        add(scrollPane);

        jta.addKeyListener(new KeyListener() {
                  /** Handle the button action */
                  public void keyPressed(KeyEvent e) {
                        // Count the letters in the text area
                        int[] count = countLetters();

                    // Set the letter count to histogram for display
                        histogram.showHistogram(count);
                  }

				public void keyReleased(KeyEvent e) {
					// TODO Auto-generated method stub
				}
				public void keyTyped(KeyEvent e) {
					// TODO Auto-generated method stub
					
				}
            });


        add(histogram);
    }

Hope this help... I am anxious to see your solution.

This post has been edited by pbl: 18 April 2008 - 11:23 AM

I works beautifully thanks. Although the histogram is on the bottom and the scrollpane is on the top. Is there any way to flip them?

otherwise changing keyadapter(i cant believe i even used this...... headsmack) to keylistener was the key

new code(that works)

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

public class lab4 extends JFrame {
	private JTextArea jta = new JTextArea();
	private Histogram histogram = new Histogram();


	  // Create a new frame to hold the histogram panel
 	 private JPanel histogramFrame = new JPanel();

		public lab4()
		{
			setLayout(new GridLayout(2,1,1,1));
			// Store text area in a scroll pane
			JTextArea jta;
			JScrollPane scrollPane = new JScrollPane(jta = new JTextArea()); //had to put this here otherwise -1 pt out of 10.... hard nosed teachers><
			jta.setWrapStyleWord(true);
			jta.setLineWrap(true);
			jta.setPreferredSize(new Dimension(800,300));

		   add(scrollPane);

		   jta.addKeyListener(new KeyListener() {
					 /* Handle the button action */
					 public void keyPressed(KeyEvent e) {
						 // Count the letters in the text area
						   int[] count = countLetters();

					   // Set the letter count to histogram for display
						   histogram.showHistogram(count);
					 }

	   public void keyReleased(KeyEvent e) {
		   
	   }
	   public void keyTyped(KeyEvent e) {
		  
	   }
			   });


		   add(histogram);
	   }



	private int[] countLetters()
	{
		// Count for 26 letters
		int[] count = new int[26];

		// Get contents from the text area
		String text = jta.getText();

		text = text.toUpperCase();

		// Count occurrence of each letter (case insensitive)
		for (int i = 0; i < text.length(); i++)
		{
		  char character = text.charAt(i);

		  if ((character >= 'A') && (character <= 'Z'))
		  {
			count[(int)character - 65]++; // The ASCII for 'A' is 65
		  }
		  }
		  return count; // Return the count array
	  }



	public static void main(String[] args) {
	   lab4 frame = new lab4();
	   frame.setLocationRelativeTo(null); // Center the frame
	   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	   frame.setTitle("lab4");
	   frame.setSize(800,600);
	   frame.pack();
	   frame.setVisible(true);

	}
}

rgfirefly24, on 18 Apr, 2008 - 01:31 PM, said:

Kind of obvious: change the order into which you add your components to the frame
Replace:

add(scrollPane);
....
add(histogram);

by:

add(histogram);
...
add(scrollPane);

pbl, on 18 Apr, 2008 - 01:46 PM, said:

thanks again... I am so tired right now in my last weeks of classes learning 4 different languages at once and its all just blurring together. i will never attempt to learn Java, VB.Net, C#, and ASP.Net with AJAX in the same semester again.

Quote

Java is ~ same as C#, C#.Net IS SAME AS VB.Net(well minor differences), ASP.Net is ~ same to VB.Net as Java is to .jsp or servlet. And well Ajax is just javascript and json/xml. Well thy should be blurred together, thy are not all that different.