A question about JScrollPane

Question

Hello,
I would like to create a Swing window that its size is (700,500) and it stores data that is recieved from user.
The size of input from user is unknown, so I want that there'll be a scrollPane in axes X and Y.
The problem: scrollPane doesn't fits to the data. How can I solve this?
public void buildGUI(List<String> classList, Map<String, ClassData> classes)
     JFrame f = new JFrame("C");
     f.getContentPane().add(new JScrollPane(new GraphPanel(classList,classes)));
     f.setSize(700, 500);
     f.setLocationRelativeTo(null);
     f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
     f.setVisible(true);
class GraphPanel extends JPanel
{     List<String> classList;
     Map<String, ClassData> classes;
     List<InfoRect> nodes;
     Map<InfoRect, String> edgesToBuild;
public GraphPanel(List<String> classList, Map<String, ClassData> classes)
{ this.classList = classList;
     this.classes = classes;
     //     JLabel label = new JLabel("C");
// label.setFont(new Font("Serif", Font.BOLD, 28));
// label.setHorizontalAlignment(0);
     //add(label);
//setPreferredSize(new Dimension(700,500));
     // super();
setBackground(Color.WHITE);
/* JLabel label = new JLabel("A label");
     label.setFont(new Font("Serif", Font.PLAIN, 14));
     label.setForeground(new Color(0xffffdd));
     add(label);*/
public void paintComponent(Graphics g)
     setPreferredSize(new Dimension(700,500));
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
     Font font = new Font("Serif", Font.BOLD, 28);
     FontMetrics metrics = g2.getFontMetrics(font);
     int hgt = metrics.getHeight();
// get the advance of my text in this font and render context
int adv = metrics.stringWidth("C");
     g2.setFont(font);
     g2.drawString("C", 70, 30);
     setBackground(Color.WHITE);
     printFile(g2);
Edited by: shira on Dec 30, 2007 5:49 AM

Answer 1

Your jscrollpane is being created anonymously, and there is no way to set the preferred size of this component. I suggest that you create a jscrollpane variable and that you set the preferred size on this variable. I also suggest that when posting code, you use code tags (by pressing the code button after highlighting your block of code), and I suggest that you paste compilable code. Something like so:
import java.awt.BorderLayout;
import java.awt.Dimension;
import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
class ScrollPaneDemo extends JPanel
    private JTextArea textArea = new JTextArea(20, 120);
    ScrollPaneDemo()
        setLayout(new BorderLayout());
        setBorder(BorderFactory.createEmptyBorder(15, 15, 15, 15));
        textArea.setWrapStyleWord(true);
        textArea.setLineWrap(true);
        fillWithText(textArea);
        JScrollPane myScrollPane = new JScrollPane(textArea);
        //**** this is the key step here ***
        myScrollPane.setPreferredSize(new Dimension(700, 500));
        add(myScrollPane, BorderLayout.CENTER);
    private void fillWithText(JTextArea textArea2)
        for (int i = 0; i < 10; i++)
            for (int j = 0; j < strings.length; j++)
                textArea2.append(strings[j] + "\n\n");
            textArea2.append("\n");
    private static void createAndShowUI()
        JFrame frame = new JFrame("ScrollPaneDemo");
        frame.getContentPane().add(new ScrollPaneDemo());
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    public static void main(String[] args)
        java.awt.EventQueue.invokeLater(new Runnable()
            public void run()
                createAndShowUI();
    private String[] strings =
      "Four score and seven years ago our fathers brought forth on this continent a new nation, " +
      "conceived in Liberty, and dedicated to the proposition that all men are created equal.",
      "Now we are engaged in a great civil war, testing whether that nation, or any nation, " +
      "so conceived and so dedicated, can long endure. We are met on a great battle-field of " +
      "that war. We have come to dedicate a portion of that field, as a final resting place for " +
      "those who here gave their lives that that nation might live. It is altogether fitting and " +
      "proper that we should do this.",
      "But, in a larger sense, we can not dedicate�we can not consecrate�we can not hallow�this " +
      "ground. The brave men, living and dead, who struggled here, have consecrated it, far " +
      "above our poor power to add or detract. The world will little note, nor long remember " +
      "what we say here, but it can never forget what they did here. It is for us the living, " +
      "rather, to be dedicated here to the unfinished work which they who fought here have thus " +
      "far so nobly advanced. It is rather for us to be here dedicated to the great task " +
      "remaining before us � that from these honored dead we take increased devotion to that " +
      "cause for which they gave the last full measure of devotion � that we here highly resolve " +
      "that these dead shall not have died in vain � that this nation, under God, shall have a " +
      "new birth of freedom � and that government of the people, by the people, for the people, " +
      "shall not perish from the earth."
}Edited by: Encephalopathic on Dec 30, 2007 6:54 AM