Discussions

public class Ball extends Actor { /** * Responds to motion control from the arrow keys and removes * any buttons from the world when it intersects them. */ public void act() { handleKeyPress(); lookForButton(); } /** * Handles input from the arrow keys. */ public void handleKeyPress() { checkLeftArrow() ; checkRightArrow() ; checkUPArrow() ; checkDownArrow() ; } } /** * Checks to see if the left arrow key is being pressed. * If it is, then the ball sets its rotation angle to zero degrees * and moves backward 5 units. If it is not being pressed, * this method does nothing. */ public void checkLeftArrow() { public void act() { if (Greenfoot.isKeyDown("left") { setRotation(0); turn(-5); } } } /** * Checks to see if the right arrow key is being pressed. * If it is, then the ball sets its rotation angle to zero degrees * and moves forward 5 units. If it is not being pressed, * this method does nothing. */ public void checkRightArrow() { public void act() { if (Greenfoot.isKeyDown("right") { setRotation(0); turn(5); } } } /** * Checks to see if the up arrow key is being pressed. * If it is, then the ball sets its rotation angle to 270 degrees * and moves forward 5 units. If it is not being pressed, * this method does nothing. */ public void checkUpArrow() { public void act() { if (Greenfoot.isKeyDown("up") { setRotation(270); turn(5); } } } /** * Checks to see if the down arrow key is being pressed. * If it is, then the ball sets its rotation angle to 90 degrees * and moves forward 5 units. If it is not being pressed, * this method does nothing. */ public void checkDownArrow() { public void act() { if (Greenfoot.isKeyDown("down") { setRotation(90); turn(5); } } } public class Button extends Actor { /** * Checks to see if the ball is "touching" an object of the Button class. * If it is, then the ball removes from the World a Button that it touches. * If the ball isn't touching an object of the Button class, then this * method does nothing. */ public void lookForButton() { Actor B =getOneIntersectingObject(Ball.class) if (isTouching(Ball.Class)) { removeTouching(Ball.class) } } }

For greenfoot site administrators: I have games that are using the GIFImage import class. The games work fine on Greenfoot, but when they are uploaded to this site, they crash. Using the latest version of that class, in Greenfoot 3.5.3. Is there are trick for using GIFs on the site? I give links to games with that problem: game1 game2 This guy discussed the same problem: game3

Wie kann man ein Tor beim Fussball programieren?