How to get a different color each time I click?

Question

I am currently trying to make a scenario where every time I click a JPanel it changes a different color each time. For example I don't want to click a magenta square and get a magenta square again.

Color newColor = null;

Color[] colorArr = {Color.YELLOW, Color.MAGENTA, Color.BLACK,new Color (0x964B00),new Color (0xB57EDC)};
int ranNum = generator.nextInt(5);//generator is a .Random Object
switch (ranNum) {

    case 0:
    newColor = colorArr[0];
       break;

    case 1:
    newColor = colorArr[1];
       break;
    case 2:
    newColor = colorArr[2];
       break;
    case 3:
    newColor = colorArr[3];
       break;
    case 4:
    newColor = colorArr[4];
       break;
}

Why not just cycle through the colors instead of getting a random one each time? — Robby Cornelissen, Mar 16 '18 at 05:01
Possible duplicate of [Creating random colour in Java?](https://stackoverflow.com/questions/4246351/creating-random-colour-in-java) — Jai, Mar 16 '18 at 05:02
Add the colors to a `List`, shuffle the list and pop a color off the top each time till the list is empty - rinse and repeat — MadProgrammer, Mar 16 '18 at 05:02
What is the need of switch case here? Why you are not just doing newColor = colorArr[ranNum] ? — Amit Bera, Mar 16 '18 at 05:42

Emre Acar · Answer 1 · 2018-03-16T16:26:03.667

0

you should define a global variable that holds the old color value.

int oldNum;
Color[] colorArr = {Color.YELLOW, Color.MAGENTA, Color.BLACK,new Color (0x964B00),new Color (0xB57EDC)};

    void changeColor(){
        Color newColor = null;
        int ranNum;
        do{
            ranNum = generator.nextInt(5);//generator is a .Random Object
        }while(oldNum == ranNum);
        oldNum = ranNum;
        newColor = color[ranNum];
    }

edited Mar 16 '18 at 16:26

answered Mar 16 '18 at 05:50

Emre Acar

920
9
24

How would I initialize oldNum? – Xander Delpin Mar 16 '18 at 16:24
@XanderDelpin its a primitive type, it wont be null in any circumstances. i forgot to change its value though, edited right now. – Emre Acar Mar 16 '18 at 16:26
@XanderDelpin in the beginning, it will be -1, if you are curious. – Emre Acar Mar 16 '18 at 16:28

How to get a different color each time I click?

1 Answers1