what's wrong with my code? im getting error "Closure containing control flow statement cannot be used with result builder 'ViewBuilder' " next to my for loop...
//
// ContentView.swift
// Bouncing Balls Simulation without ChatGPT's Code
//
// Created by Hillary Basile on 3/30/25.
//
import SwiftUI
import Foundation
import CoreGraphics
class Balls
{
//var color: String
var xPosition: Int
var yPosition: Int
var xVelocity: Int
var yVelocity: Int
var radius: Int
var gravity: CGFloat
var restitution: Int
var other: Balls?
init(xPosition: Int, yPosition: Int, xVelocity: Int, yVelocity: Int, radius: Int, gravity: CGFloat, restitution: Int)
//ADD COLOR
{
//self.color = color
self.xPosition = xPosition
self.yPosition = yPosition
self.xVelocity = xVelocity
self.yVelocity = yVelocity
self.radius = radius
self.gravity = gravity
self.restitution = restitution
}
let ball1: Balls = Balls (xPosition: 100, yPosition: 100, xVelocity: 3, yVelocity: 0, radius: 3, gravity: 0.3, restitution: 1)
let ball2: Balls = Balls (xPosition: 200, yPosition: 50, xVelocity: -2, yVelocity: 2, radius: 3, gravity: 0.3, restitution: 1)
let ball3: Balls = Balls (xPosition: 300, yPosition: 150, xVelocity: 4, yVelocity: -3, radius: 3, gravity: 0.3, restitution: 1)
struct UserView: View
{
var timer = Timer.publish(every: 0.01, on: .main, in: .common).autoconnect()
var body: some View
{
VStack
{
//Background color
Color.gray.edgesIgnoringSafeArea(.all)
//var balls [Int] = [ball1; ball2; ball3]
@ViewBuilder
func updateBalls()
{
for item in Balls
{
Circle()
.fill(Color.black)
.frame(width: 50, height: 50)
.position(Balls[].xPosition, Balls[].yPosition)
.onReceive(timer)
{
self.yVelocity += self.gravity
self.xPosition = CGPoint(self.xPosition + self.xVelocity)
self .yPosition = CGPoint (self.yPosition + self.yVelocity)
if self.yPosition >= 500 - 25
{
self.yPosition = 500 - 25
self.yVelocity = -self.yVelocity * self.restitution
}
if self.xPosition <= 25
{
self.xPosition = 25
self.xVelocity = -self.xVelocity
}
if self.xPosition >= 375
{
self.xPosition = 375
self .xVelocity = -self.velocityX
}
let dx: int = other.xPosition - self.xPosition
let dy: int = other.yPosition - self.yPosition
let distance: int = sqrt (dx * dx + dy * dy)
if distance < self.radius + other.radius
{
self.xVelocity = -self.xVelocity * self.restitution
self.yVelocity = -self.yVelocity * self.restitution
other.xVelocity = -other.xVelocity * self.restitution
other.yVelocity = -other.yVelocity * self.restitution
}
}
updateBalls()
}
}
}
}
}
}
#Preview
{
ContentView()
}
}
