Question

So I have a JFrame in which inside of it I have a JScrollPane and inside the JScrollPane I have a JPanel. I have a button click mouse listener that modifies the JPanel inside the JScrollPane. The code in the mouse listener is:

@Override
    public void mouseClicked(MouseEvent arg0) {

            searchResult.updateInfo();

        }

The method updateInfo is adding a bunch of JPanel into the searchResult JPanel. After I click the button associated with this listener, nothing happens, but when I resize the JFrame.. it updates the view.. why is this?

I tried repaint the JFrame, but it did not solve my problem

Answer 1

After adding/removing components from a visible GUI you need to tell the panel to layout the components so the preferred size can be recalculated. You need to add:

searchResult.revalidate();
searchResult.repaint(); // sometimes needed

Then if the preferred size is greater than the size of the scrollpane scrollbars will appear.