How to use JScrollPane alongside JTextArea?

Question

I have written this code. Here I want to make a JScrollPane work with JTextArea. But it is not working at all. Earlier I almost did the same thing. It used to work. Please provide a solution. Thanks in advance. I have posted the code.

    protected void startServerProcess(int port) {
    serverFrame = new JFrame("SERVER NOTIFICATIONS PANEL | Labyrinth Developers");
    serverFrame.setSize(500, 500);
    serverFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    serverFrame.setLocationByPlatform(true);
    serverFrame.setLocationRelativeTo(null);
    serverFrame.setVisible(true);

    notificationsTA = new JTextArea();
    notificationsTA.setBounds(0,0,466,500);
    notificationsTA.setLineWrap(true);
    notificationsTA.setRows(1000);

    notificationsSP = new JScrollPane();
    notificationsSP.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
    notificationsSP.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
    notificationsSP.setViewportView(notificationsTA);
    notificationsSP.setWheelScrollingEnabled(true);
    notificationsSP.setBounds(470, 0, 30, 500);

    serverFrame.add(notificationsTA);
    serverFrame.add(notificationsSP);
}

score 2 · Accepted Answer · edited Jun 20 '20 at 09:12

JTextArea is already added in JScrollPane so there is no need to add it again in JFrame as well. Remove below line:

serverFrame.add(notificationsTA);

You can add the component in the viewport of scroll pane using its Constructor as well that internally calls JScrollPane#setViewport() method.

notificationsSP = new JScrollPane(notificationsTA);

Some Points:

JFrame be default uses BorderLayout and you can add only single component in each section (North, South, East, West and Center).

Read more How to Use BorderLayout
Call serverFrame.setVisible(true); in the end after adding all the components.
Don't use setBounds() at all. Just leave it for Layout Manager to set the size and position of the components.
Use SwingUtilities.invokeLater() to make sure that EDT is initialized properly.

Read more
- Why to use SwingUtilities.invokeLater in main method?
- SwingUtilities.invokeLater

Thanks...you are right...I forgot that constructor for JScrollPane...My bad I should have used Javadocs....And regarding setVisible...yeah we should use at last to avoid flickers and actually I have used invokeLater but this was an excerpt of the code. Thanks once again to remind me..:) — Siddharth Kamaria, Jun 07 '14 at 10:03

How to use JScrollPane alongside JTextArea?

1 Answers1

Some Points: