JButton的图标没有改变（UNO纸牌游戏）

Question

I'm implementing a UNO game using sockets and stuff. So far I've been working on the GUI for each client, I've succeeded when getting a random set of cards for each player and a random central card but got stuck on the following: I'm using a button to represent each card of a hand, say I want to select a Red card (because the central card is also Red) I've done all the validation methods that allow you to place or not to place your card. But the central button's icon isn't changing (the central card variable changes but not the button's icon that represents it).

I read this question and tried to use the SwingUtilities.invokeLater but the icon doesn't change ( Dynamically change jButton icon ).

Here's the code where I change the JButton's icon:

public void setBtnIcon( final javax.swing.JButton btn,  final modelo.Card c) {
    SwingUtilities.invokeLater(new Runnable() {
        @Override
        public void run() {
            btn.updateUI();
            Color color = c.getColor();
            btn.setBackground(color);
            if (c instanceof modelo.NumberCard) {
                short value = ((modelo.NumberCard) c).getValue();


                String str = Short.toString(value);
                btn.setIcon(new javax.swing.ImageIcon(getClass().getResource("/jugadoruno/vista/" + str + ".png")));

            } else if (c instanceof modelo.ActionCard) {
                modelo.ActionType t = ((modelo.ActionCard) c).getActionType();
                String str = t.toString();

                btn.setIcon(new javax.swing.ImageIcon(getClass().getResource("/jugadoruno/vista/" + str + ".png")));

            }

        }
    });
}

It receives a card (to get it's color, value/actionType), it changes the JButton's background to that same color, and searches for the correct icon (if a card is red and has a value 1 it will change the Button's background to red and search for 1.png that is a transparent image with the number 1)

If there's a better way to doing this I'll be pleased to know it. Right now It just sets the icon at the beginning of the execution. Thanks for your time!

Answer 1

Two things to check:

1. Make sure you're calling setBtnIcon inside some kind of event listener such that it fires when you want it to. I couldn't tell from your original question whether "it just sets the icon at the beginning of execution" meant the method was only being called once.
2. Run through your code with a debugger (or add a print statement or two) to make sure that the result of getClass().getResource(...) isn't null . Getting co-located resources can be a tricky thing, especially if you're distributing your app in a JAR file.

Answer 2

您是否尝试过删除JButton的“最终”语句？

Answer 3

Solved: I wasn't calling the above function within the update function on the Observer, silly thing but true; thanks for your help, some of your answers were helpful. the client window is the observer, when centralCard is changed, then I need to call the function I wrote above.