Presenting colour every time button is pressed (lambda expression)

user_8726446 0
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Whenever the button is pressed, I want to set a certain colour. Right now the user can write an int and the corresponding colour is presented (without typing the corresponding int every time). I want to change this though. Every time the user clicks the button, the next colour shall be presented, but I don't know how to rewrite the code. I tried a do while and for loop, but I had problems with the variable used in lambda expression (which apparently should be final)?

board.setButton2Text("Select"); 
board.setButton2Action(() -> {
    int c = 0;
    while(!(c > 0 && c < 7)) {
        try {
            c = IO.inputInt("Type an int ranging from 1 to 6");
        } catch (RuntimeException e) {
            continue;
        }
    }
    currentCode.setColor(selectedCircle, c);
    drawCode(X_START, Y_START + LINE_SPACING * (6 - currentTry), currentCode);
});

Right now it looks like this

enter image description here

button lambda java
1 Answers

Change your code that reacts to a button click. That code should:

  1. Get the currently set color.
  2. Add one to that color number.
  3. If that new number exceeds the limit (0-7), then cycle around.
  4. Set the color to the new color number.

Something like this:

board.setButton2Action( () -> {
        // On each click of the button, rotate to the next color in a sequence of colors numbered 0-7. 
        int c = currentCode.getColor( … ) ; // TODO: Add assertion tests to verify you get back a valid value as expected.
        c = ( c + 1 ) ;  // Increment the color.
        if( c == 8 ) {  // If past the limit…
            c = 0 ;     // …go back to first number.
        }
        currentCode.setColor( selectedCircle , c ) ;
        drawCode( X_START , Y_START + LINE_SPACING * ( 6 - currentTry ) , currentCode ) ;
    }
);

I do not see how your lambda would be a problem here. Changing to the code as I showed here does not involve any additional objects outside the scope of the lambda.

user_6427060
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