So I am working on a basic game where it is an ant vs a spider (I won't get into all the details) but I need help making it so when a key is pressed an actor (SpiderWeb) appears at another actor (Spider). Any help would be appreciated.
madarnt wrote ...
2016/4/15
Help with some programming
It can be made like this:
To prevent many SpiderWebs from appearing at once, you can use a boolean to track the space key.
if (Greenfoot.isKeyDown("space"))
{
addObject(new SpiderWeb(), getX(), getY());
}I'm getting an error with the "addObject" saying "cannot find symbol - method addObject(Web, int, int). Anything you can do to help? Oh and by the way it was actually "Web" not "SpiderWeb" my mistake.
public class Spider extends Actor
{
public void act()
{
if (Greenfoot.isKeyDown ("w"))
move (4);
if (Greenfoot.isKeyDown ("s"))
move(-4);
if (Greenfoot.isKeyDown ("a"))
turn (-5);
if (Greenfoot.isKeyDown ("d"))
turn (5);
Actor Ant1;
Ant1 = getOneObjectAtOffset(0, 0, Ant1.class);
if (Ant1 != null)
{
World world;
world = getWorld();
world.removeObject(Ant1);
}
if (Greenfoot.isKeyDown("e"))
{
addObject(new Web(), getX(), getY());
}
}
}
There is no 'addObject' method in the Actor class API -- it is a part of the World class API. You need to execute the method on a World type object. The Actor class API has a method that returns the World object that an actor is in; it is the 'getWorld' method. You can call the 'addObject' method on that:
This will not work if the actor (the Spider object) is removed from the world before using it.
getWorld().addObject(new Web(), getX(), getY());
I don't understand Boolean can I have help with this?
private boolean web = true;
if (Greenfoot.isKeyDown("e") && boolean.web = true)
{
getWorld().addObject(new Web(), getX(), getY());
private boolean web = false;
}
The boolean is to track the state of the "e" key -- so you can detect when it is initially pressed or released:
// the boolean field
private boolean eKeyDown;
// in your code
if (eKeyDown != Greenfoot.isKeyDown("e")) // is state changing
{
eKeyDown = !eKeyDown; // save new state
if (eKeyDown) // was just pressed
{
getWorld().addObject(new Web(), getX(), getY());
}
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