Fixed Width JTextArea or JTextPane with 'as-needed' height

Question

I'm trying to solve the above problem. I want to implement a text component that will have a defined width (say 200px) but will expand in height so that all text within the component is visible. I do not want a scrollbar.
The word wrapping capabilities of the above named components get me half way there however I can't seem to pull a preferred height from them based on a set width. I've tried many combinations of setPreferredSize(), setSize() etc and I can't seem to fiqure it out.
Any hints.
(As an added bonus It'd be good to add scrollbars 'ONLY' when the height of the text component now fills the vertical height of the screen)
Thanks very much
Adam

Answer 1

This is perhaps not the solution for all the things you want to do, but it might be some kind of starting point (?).
import java.awt.*;
import javax.swing.*;
class Testing extends JFrame
   private final static int MAX_WIDTH = 200;
   private final static int START_HEIGHT = 200;
   private final static int TASKBAR_HEIGHT = 25;
   public Testing()
      //Layout components
      JTextArea textArea = new JTextArea();
      textArea.setColumns(5);
      textArea.setLineWrap(true);
      textArea.setWrapStyleWord(true);
      textArea.setText("Millions and millions of test text all over the goddamn place");
      JScrollPane scroll = new JScrollPane(textArea);
      scroll.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
      getContentPane().add(scroll, BorderLayout.CENTER);
      //Set appropriate operation for closing application window
      setDefaultCloseOperation(EXIT_ON_CLOSE);
      //Start UI thread
      pack();
      //Since UI thread is started all UI modifications must now run in UI thread
      try
         //Calculate application size and determine appropriate position on screen
         SwingUtilities.invokeAndWait(new Runnable()
            public void run()
               Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
               int screenHeight = (int) (screenSize.getHeight() - TASKBAR_HEIGHT);
               int applicationHeight = START_HEIGHT;
               if (applicationHeight > screenHeight)
                  applicationHeight = screenHeight;
               setSize(MAX_WIDTH, applicationHeight);
               int windowPositionX = (int) (screenSize.getWidth() - MAX_WIDTH);
               int windowPositionY = screenHeight - applicationHeight;
               setLocation(windowPositionX, windowPositionY);
         //Make aplication visible
         SwingUtilities.invokeLater(new Runnable()
            public void run()
               setVisible(true);
      } catch (Exception e)
   public static void main(String[] args)
      new Testing();
}You have to elaborate further if you want to use "dynamic" height depending of the amount of text in the text area (instead of using the above solution with final's for widht and height).
Since you mentioned the systray the above code takes into account that you use windows and the actual height will diminish due to the task bar (note that the value of 25 px might be different on, for example, Linux with KDE and MacOS X).
You also might want to remove the "pack()" since "setSize(x, y)" is used (I only added it when I did some elabortions and I did not remove it). If you remove pack you don't have to put the remaining code in the UI thread. If you don't remove pack, you probably should merge the two "invoke" calls into one...