在Java Swing中刷新JPanel

Question

Let's suppose I've a list of String like this

List<String> button_names={"Button1","Button2","Button3","Button4"};

I've to insert JButtons with those texts in a JPanel so I do

for (int i=0; i<button_names.length; i++)
   myJPanel.add(new JButton(button_name[i]));

My question is... If my model (in this case, my List button_names) changes for any reasons, how can I refresh my JPanel in order to show that change? Should I do

myJPanel.removeAll()

and insert again my JButtons()? Thank you in adance

Answer 1

Yes removeAll and then reinserting new buttons is the easiest and generally the best way to go. Otherwise, you have to start figuring out which buttons have been removed, which have been added, and where in the list these new buttons are. Also, buttons in the list should change position I guess, so you'd have to cover that case to.

You can write a method like this that you could use in initial creation, and when you want to reload the list

void addButtonsToPanel(JPanel p) {
  p.removeAll();
  for (int i=0; i<button_names.length; i++)
   myJPanel.add(new JButton(button_name[i]));
  validate();
  repaint();
}