URGENT!

Hey guys,

I'm having a huge problem and can't understand how to fix it.
I was trying to recreate an Xcode app project with a Xcode Playground, now the point is that in Xcode Project on the side of the screen there are the options to add files.
Like this:

And in the Playground it is like this:

But here, when I add the Swift Files under Shared Sources, and create the ContentView() in Main - Xcode Playground, it says me that it can't find the Helicopter, Pixel, Obstacle, so it can't find the Shared Recourses' files.

Here's all the code. ContentView(Main):

import SwiftUI
import PlaygroundSupport
 
struct ContentView: View {
    
    @State private var heliPosition = CGPoint(x:100, y: 100)
    @State private var obstPosition = CGPoint(x:1000, y: 300)
    @State private var isPaused = false
    @State private var score = 0
    
    @State var timer = Timer.publish(every: 0.1, on: .main, in: .common).autoconnect()
    
    var body: some View {
        
        GeometryReader { geo in
            
            
            ZStack{
                
                Helicopter()
                    .position(self.heliPosition)
                    .onReceive(self.timer) {_ in
                        self.gravity()
                    }
                
                Obstacle()
                    .position(self.obstPosition)
                    .onReceive(self.timer) {_ in
                        self.obstMove()
                    }
                
                Text("\(self.score)")
                    .foregroundColor(.white)
                    .position(x: geo.size.width - 100, y: geo.size.height / 10 )
                
                self.isPaused ? Button("Resume") { self.resume() } : nil
                
                
            }
            .frame(width: geo.size.width, height: geo.size.height)
            .background(Color.black)
            .gesture(
                TapGesture()
                    .onEnded{
                        withAnimation{
                            self.heliPosition.y += 100
                        }
                    })
            .onReceive(self.timer) { _ in
                self.collisionDetection();
                self.score += 1
            }
        }
        .edgesIgnoringSafeArea(.all)
    }
    
    
    func gravity() {
        withAnimation{
            self.heliPosition.y -= 20
        }
    }
    
    func obstMove() {
        
        if self.obstPosition.y > 0
        {
            withAnimation{
                self.obstPosition.y -= 20
            }
        }
        else
        {
            self.obstPosition.x = 1000
            self.obstPosition.y = CGFloat.random(in: 0...500)
            
        }
    }
    
    func pause() {
        self.timer.upstream.connect().cancel()
    }
    
    func resume() {
        
        self.timer = Timer.publish(every: 0.1, on: .main, in: .common).autoconnect()
        
        self.obstPosition.x = 1000 
        self.heliPosition = CGPoint(x: 100, y: 100)
        self.isPaused = false
        self.score = 0
    }
    
    func collisionDetection() {
        
        if abs(heliPosition.x - obstPosition.x) < (25 + 10) && abs(heliPosition.y - obstPosition.y) < (25 + 100) {
            self.pause()
            self.isPaused = true
        }   
    }   
}
 
PlaygroundPage.current.setLiveView(ContentView())
 

Pixel:

import SwiftUI
 
public struct Pixel: View {
    let size: CGFloat
    let color: Color
    
    
    public var body: some View {
        Rectangle()
            .frame(width: size, height: size)
            .foregroundColor(color)
    }
}
 

Helicopter:

import SwiftUI
 
public struct Helicopter: View {
    
    let rows = 5
    let columns = 5
    let size: CGFloat = 10
    let heliBlocks: [[Color]] = [[.gray,.gray,.gray,.gray,.gray],
                                 [.clear,.clear,.green,.clear,.clear],
                                 [.green,.green,.green,.green,.gray],
                                 [.clear,.clear,.green,.green,.green],
                                 [.clear,.clear,.gray,.clear,.gray]]
    
    
    public var body: some View {
        
        VStack (spacing: 0) {
            ForEach((0...self.rows - 1), id: \.self) { row in
                HStack (spacing: 0) {
                    ForEach((0...self.columns - 1), id: \.self) { col in
                        VStack (spacing: 0) {
                            Pixel(size: self.size, color: self.heliBlocks[row][col])
                        }
                    }
                }
            }
        }
    }
}
 

Obstacle:

import SwiftUI
 
public struct Obstacle: View {
    
    let width: CGFloat = 20
    let height: CGFloat = 200
    
    public var body: some View {
        
        Rectangle()
            .frame(width: width, height: height)
            .foregroundColor(Color.green)
        
    }
}
 

Guys please, if anyone knows how to fix this, please help me. I will be grateful to you.