You need to wrap the body you want to be executed in the for
loop in braces
for (Bird bird : birds) {
bird.fly();
g.setColor(bird.getColor());
Point pos = bird.getPosition();
g.fillOval((int)pos.getX()*PIXELS, (int)pos.getY()*PIXELS,
PIXELS, PIXELS);
panel.sleep(500);
}
Otherwise, the body of the for
loop is the next statement following the )
. So it is equivalent to
for (Bird bird : birds)
bird.fly();
// bird is not in scope anymore
g.setColor(bird.getColor());
Point pos = bird.getPosition();
g.fillOval((int)pos.getX()*PIXELS, (int)pos.getY()*PIXELS,
PIXELS, PIXELS);
panel.sleep(500);
As Darien has said in the comments, indentation is not part of the Java language, it has no bearing on the syntax. But you should use it to make your code easier to read, as expressed in the Java code style conventions.