JTextArea: size dynamic with text

Question

I''m trying to size a JTextArea according to the text that is occupy it.
The width I have from another JPanel, but the height I can't get right.
I need to get the number of lines that the text will occupy and then set the size accordingly.
As it is, I've hard-coded the number of lines, even so, that doesn't work. e.g. if i set # of lines = 5, it still shows only 2, though the dlg box can be resized by hand to show them all.
Any suggestions?
public class TextPanel extends JPanel {
    private final Insets insets =  new Insets(10,20,10,20); // top, left, bottom, right
    private JTextArea textArea;
    private FontMetrics metrics;
    private double widthButtonPanel;
     * @param message
     * @param dimension dimensions of button panel
    public TextPanel(String message, Dimension dimension) {
      // get bg color of panel so we can set bg of text area to same color
         Color color = getBackground();
       TextArea = new JTextArea (message);
     textArea.setLineWrap(true);
     textArea.setWrapStyleWord(true);
     textArea.setBackground(color);
       TextArea.setMargin(insets);
     // this will be width of the text area
     // height can't be set until painting it because we need to get the text size
       widthButtonPanel = dimension.getWidth();
     add(textArea);
     * override default insets
    public Insets getInsets()
         return insets;
    @Override
     * override in order to set height of text area
     * @param g Graphics
    public void paintComponent(Graphics g)
         // automatically called when repaint
         super.paintComponent(g);
     Font font = this.getFont();
         Graphics graphics = this.getGraphics();
         // get metrics from the graphics
         metrics = graphics.getFontMetrics(font);
     // get the height of a line of text in this font and render context
       // line height must be that of text only, not space above and below
         final int HEIGHT_SPACE = 7; // empirically derived
     int heightTextAreaLine = metrics.getHeight() + HEIGHT_SPACE;
     // set height
     final int numberOfLines = 5;
        // truncate double, doesn't matter because it is *.0 anyway
     Dimension newDimension = new Dimension((int)widthButtonPanel, heightTextAreaLine * numberOfLines);
        TextArea.setPreferredSize(newDimension);
        //textArea.setMaximumSize(newDimension);
        TextArea.setMinimumSize(newDimension);
}Edited by: allelopath on Jan 19, 2009 2:33 PM

Answer 1

You can get the size following the steps.
1. create dummy textarea and set your text to it.
2. dummyarea.setSize(new Dimension(desiredWidth, Short.MAX_VALUE));
3. Dimension pref=dummyarea.getPreferredSize();
pref.height is the height textarea need to be.
Regards,
Stas