javafx - Removing GraphicsContext shapes from Canvas

Question

I got a little game running and I wanted to know how I can remove/delete a shape in GraphicsContext. I wanna remove one Rectangle when one of the if statements fits it. Sadly, I do not know if there is a method to delete that.

I hope you can help me out

targets.setFill(Color.RED);
            //Problem area
            for (countCol = 1; countCol <= 10; countCol++) {
                for (countRow = 1; countRow <= 3; countRow++) {
                    targets.fillRect(countRow * gapX + startX, countCol * gapY + startY, brickW, brickH);
                    if (ballXPos + rad >= (countRow * gapX + startX) && ballXPos + rad <= (countRow * gapX + startX) + brickW && ballYPos + rad == (countCol * gapY + startY)) {
                        ballYSpeed *= -1;
                    }
                    if (ballXPos + rad >= (countRow * gapX + startX) && ballXPos + rad <= (countRow * gapX + startX) + brickW && ballYPos + rad == (countCol * gapY + startY) + brickH) {
                        ballYSpeed *= -1;
                    }
                    if (ballXPos + rad == (countRow * gapX + startX) && ballYPos + rad >= (countCol * gapY + startY) && ballYPos + rad <= (countCol * gapY + startY) + brickH) {
                        ballXSpeed *= -1;
                    }
                    if (ballXPos + rad == (countRow * gapX + startX) + brickW && ballYPos + rad >= (countCol * gapY + startY) && ballYPos + rad <= (countCol * gapY + startY) + brickH) {
                        ballXSpeed *= -1;
                    }
                }
            }

Answer 1

等待大神答复