Java boolean problem

Hello,

I'm new to java and this forum and I stumbled on this problem. It would be great if somebody could help me with this!:confused:

BTW i'm dutch and therefore the commands are in Dutch.

down here is my java logo program (and the error is under my program):

Quote:

/*
* @(#)BalUitd.java 11/03/15
*
* JavaLogo Project
*
*/
import logotekenap.*;

public class BalUitd extends TekenApplet
{
double xverander;
double yverander;
double xstap;
double ystap;
int teller;

public void initialiseer()
{
maakTraceMogelijk();
maakAnimatieMogelijk();
xstap=0;
ystap=0;
xverander=1;
yverander=0.5;
}

public void tekenprogramma()
{
bal(xstap, ystap, "rood");
}

public void bal(double xstap, double ystap, String kleur)
{
pen.vooruit(ystap+yverander);
pen.rechts(90);
pen.vooruit(xstap+xverander);
pen.links(90);
pen.vulAan(kleur);
pen.vooruit((360*0.5)/(2*Math.PI));
pen.rechts(90);
int teller;
teller =0;
while (teller < 360)
{
pen.vooruit(0.4);
pen.rechts(1);
teller=teller+1;
}
pen.vulUit();
}

public void animatie(double xstap, double ystap, double xverander, double yverander)
{
while(animatieLopend())
{

if(xstap=300)
{
xverander=-xverander;
}

else if(xstap=-300)
{
xverander=-xverander;
}

else if(ystap=-300)
{
yverander=-yverander;
}

else if(ystap=300)
{
yverander=-yverander;
}
}
tekenOpnieuw();
}

}

ERROR: (They refer to the Animatie segment)

Quote:

--------------------Configuration: BalUitd - j2sdk1.4.2_05 <Default> - <Default>--------------------
H:\MyProjects\BalUitd\BalUitd.java:133: incompatible types
found : double
required: boolean
if(xstap=300)
^
H:\MyProjects\BalUitd\BalUitd.java:138: incompatible types
found : double
required: boolean
else if(xstap=-300)
^
H:\MyProjects\BalUitd\BalUitd.java:143: incompatible types
found : double
required: boolean
else if(ystap=-300)
^
H:\MyProjects\BalUitd\BalUitd.java:148: incompatible types
found : double
required: boolean
else if(ystap=300)
^
4 errors

Process completed.

THANKS!
:):)