Blinking integers in Java

Question

I want to make a program that displays random numbers, bliking one at a time in a JLabel or just in the console. I am making a game, where the player needs to remember the number that was displayed two blinks back in time. Does anyone know how to make the numbers blink?

You should show your work so far, so that we know what you have exact problems with. Do you know how to display a JLabel? Do you know how to change the value? If yes, then probably you can use Timer class (http://docs.oracle.com/javase/7/docs/api/java/util/Timer.html) to schedule a label update with a specific interval. — Gerino, Jan 22 '15 at 09:50
I am pretty new at this, but I do know how to display a JLabel. What I don't quite understand, is how to make a new number come up every time the JLabel blinks. — thorbear, Jan 22 '15 at 09:53

Gerino · Accepted Answer · 2015-01-22T10:36:21.027

I unfortunately don't have any GUI project handy to test it out (I might in a moment as a command line one), but I think that one way to do it is:

(I've removed the HideTask, as it gives some trouble when you want to run it again, and I don't think the task at hand really needs it - just call sleep() :) )

class ShowTask extends TimerTask {
    JLabel label;
    Random generator = new Random();
    //HideTask hTask;
    //java.util.Timer timer = new java.util.Timer();
    long period = 500; // ms

    public Task(JLabel pLabel){
        label = pLabel;
        //hTask = new HideTask(pLabel);
    }

    public void run(){
        int i = generator.nextInt(100);
        setLabel(i);
        // if you want it to go SHOW HIDE SHOW HIDE instead of SHOW SHOW SHOW then:
        //timer.schedule(hTask, period);
        // just wait
        Thread.sleep(period);
        hideLabel();
    }

    void setLabel(int i){
        ...
    }
}
/*
class HideTask extends TimerTask {
    JLabel label;

    public HideTask(JLabel pLabel){
        label = pLabel;
    }

    public void run(){
        hideLabel();
    }

    void hideLabel(){
        ...
    }
}
*/

when you want to start:

ShowTask task = new ShowTask();
long delay = 0; // ms 
long period = 1000; // ms
java.util.Timer timer = new java.util.Timer();
timer.scheduleAtFixedRate(task, delay, period);

Note, that it wasn't tested and it is just the first concept I come up with, but maybe you can work forward from it.

Blinking integers in Java

1 Answers1