How to make loop end once the last element in the array meets condition?
In my bouncing ball program, it asks the user to insert a number of balls which will be displayed on the screen and will start at the top of the canvas then drop and bounce on a line on the bottom of the canvas.
When finished = true, the animation will stop. So far the animation stops once the X position of the first ball goes past 550. How do I make the animation end once the X position of EVERY ball is more than 550?
public void multiBounce(int numBalls)
{
BouncingBall[] balls;
balls = new BouncingBall[numBalls];
int x = 50;
int y = 150;
for (int i = 0; i < balls.length; i++){
balls[i] = new BouncingBall(x, y, 16, Color.blue, ground, myCanvas);
x = x + 20;
y = y - 30;
balls[i].draw();
}
boolean finished = false;
while(!finished) {
for (int i = 0; i < balls.length; i++){
balls[i].move();
}
for (int i = 0; i < balls.length; i++){
if (balls[i].getXPosition() >= 550){
finished = true;
}
}
}
Just check for every ball whether it is beyond your desired position. This code snippet should do the work. Just replace the last for loop by the code below.
finished=true;
for (int i = 0; i < balls.length; i++){
if (balls[i].getXPosition() >= 550){
finished = finished && true; }
else{
finished=false;
break;
}
}
You should use a break statement. When its encountered inside a loop , the loop is immediately terminated and the program control resumes at the next statement following the loop . For more details see Branching Statements
public void multiBounce(int numBalls)
{
BouncingBall[] balls;
balls = new BouncingBall[numBalls];
int x = 50;
int y = 150;
for (int i = 0; i < balls.length; i++){
balls[i] = new BouncingBall(x, y, 16, Color.blue, ground, myCanvas);
x = x + 20;
y = y - 30;
balls[i].draw();
}
boolean finished = false;
while(!finished) {
for (int i = 0; i < balls.length; i++){
balls[i].move();
}
for (int i = 0; i < balls.length; i++){
if (balls[i].getXPosition() < 550){
finished = false;
break;
}
else {
finished = true;
}
}
}
}
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