在SwiftUI View中显示粒子发射器

Question

尝试使用SKScene在视图中显示粒子发射器spritekit文件。

当前代码

struct ContentView: View {

var scene: SKScene {
let scene = SKScene(fileNamed: "magicSparkles")!
scene.size = CGSize(width: 400, height: 400)
scene.scaleMode = .fill
return scene
}

var body: some View {
VStack {
Text("Hello, World!")
.padding()
SpriteView(scene: scene)
.frame(width: 400, height: 400)
.edgesIgnoringSafeArea(.all)
}
}
}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}

每当我尝试这样做时，模拟器就会抛出错误。

Moodie2 WatchKit Extension crashed due to an uncaught exception NSInvalidArgumentException. Reason: -[SKEmitterNode setScaleMode:]: unrecognized selector sent to instance 0x600003e981c0.

Answer 1

尝试使用SKScene(fileNamed: "magicSparkles")，将SKScene替换为SKEmitterNode。不确定其余代码是否可以通过

正确运行

Answer 2

我对这个问题有一个部分的答案，尽管它有一个问题，我一直无法解决手表。我在iOS设备上使用过Spritekit和SwiftUI，但从未在watchOS上使用过。我学到的第一件事是，func didMove()在watchOS上不存在，所以你必须使用func sceneDidLoad()来实现一些东西。下面的代码将在手表上放置一个发射器:

import SwiftUI
import SpriteKit
struct ContentView: View {
var scene = EmitterScene()
var body: some View {
GeometryReader { geometry in
SpriteView(scene: scene)

}
}
}
class EmitterScene: SKScene {

override func sceneDidLoad() {
if let emitter = SKEmitterNode(fileNamed: "magicSparkles"){
emitter.position = CGPoint(x: frame.width / 2, y: frame.height / 2)
emitter.zPosition = -1
addChild(emitter)
}
}
}

我遇到的问题是发射器粒子没有正确出现。它们太大了，你必须对发射器进行调整，使其足够密集，以便它们经常显示出来，但它们似乎被放大到与表盘本身几乎相同的大小。我不知道如何解决这个问题。

Answer 3

所以有两件事:

1. SpriteKit内容不显示在Xcode预览，只有在模拟器应用程序或设备上，供您参考!
你只需要将粒子添加到SpriteKit场景中并将其放置在视图中，而不仅仅是一个发射器。

代码(忽略花的形状):

import SwiftUI
import SpriteKit
struct flowerhshape: Shape {
func path(in rect: CGRect) -> Path {
var path = Path()
let width = rect.size.width
let height = rect.size.height
path.move(to: CGPoint(x: 0, y: 0.66071*height))
path.addCurve(to: CGPoint(x: 0.19416*width, y: 0.83929*height), control1: CGPoint(x: 0, y: 0.75929*height), control2: CGPoint(x: 0.08698*width, y: 0.83929*height))
path.addCurve(to: CGPoint(x: 0.30444*width, y: 0.80786*height), control1: CGPoint(x: 0.23532*width, y: 0.83929*height), control2: CGPoint(x: 0.2726*width, y: 0.82786*height))
path.addLine(to: CGPoint(x: 0.30288*width, y: 0.82143*height))
path.addCurve(to: CGPoint(x: 0.49704*width, y: height), control1: CGPoint(x: 0.30288*width, y: 0.92*height), control2: CGPoint(x: 0.38987*width, y: height))
path.addCurve(to: CGPoint(x: 0.6912*width, y: 0.82143*height), control1: CGPoint(x: 0.60422*width, y: height), control2: CGPoint(x: 0.6912*width, y: 0.92*height))
path.addLine(to: CGPoint(x: 0.68965*width, y: 0.80786*height))
path.addCurve(to: CGPoint(x: 0.79993*width, y: 0.83929*height), control1: CGPoint(x: 0.72071*width, y: 0.82786*height), control2: CGPoint(x: 0.75876*width, y: 0.83929*height))
path.addCurve(to: CGPoint(x: 0.99409*width, y: 0.66071*height), control1: CGPoint(x: 0.9071*width, y: 0.83929*height), control2: CGPoint(x: 0.99409*width, y: 0.75929*height))
path.addCurve(to: CGPoint(x: 0.88302*width, y: 0.5*height), control1: CGPoint(x: 0.99409*width, y: 0.58929*height), control2: CGPoint(x: 0.94826*width, y: 0.52857*height))
path.addCurve(to: CGPoint(x: 0.99409*width, y: 0.33929*height), control1: CGPoint(x: 0.94826*width, y: 0.47143*height), control2: CGPoint(x: 0.99409*width, y: 0.41071*height))
path.addCurve(to: CGPoint(x: 0.79993*width, y: 0.16071*height), control1: CGPoint(x: 0.99409*width, y: 0.24071*height), control2: CGPoint(x: 0.9071*width, y: 0.16071*height))
path.addCurve(to: CGPoint(x: 0.68965*width, y: 0.19214*height), control1: CGPoint(x: 0.75876*width, y: 0.16071*height), control2: CGPoint(x: 0.72149*width, y: 0.17214*height))
path.addLine(to: CGPoint(x: 0.6912*width, y: 0.17857*height))
path.addCurve(to: CGPoint(x: 0.49704*width, y: 0), control1: CGPoint(x: 0.6912*width, y: 0.08*height), control2: CGPoint(x: 0.60422*width, y: 0))
path.addCurve(to: CGPoint(x: 0.30288*width, y: 0.17857*height), control1: CGPoint(x: 0.38987*width, y: 0), control2: CGPoint(x: 0.30288*width, y: 0.08*height))
path.addLine(to: CGPoint(x: 0.30444*width, y: 0.19214*height))
path.addCurve(to: CGPoint(x: 0.19416*width, y: 0.16071*height), control1: CGPoint(x: 0.27337*width, y: 0.17214*height), control2: CGPoint(x: 0.23532*width, y: 0.16071*height))
path.addCurve(to: CGPoint(x: 0, y: 0.33929*height), control1: CGPoint(x: 0.08698*width, y: 0.16071*height), control2: CGPoint(x: 0, y: 0.24071*height))
path.addCurve(to: CGPoint(x: 0.11106*width, y: 0.5*height), control1: CGPoint(x: 0, y: 0.41071*height), control2: CGPoint(x: 0.04582*width, y: 0.47143*height))
path.addCurve(to: CGPoint(x: 0, y: 0.66071*height), control1: CGPoint(x: 0.04582*width, y: 0.52857*height), control2: CGPoint(x: 0, y: 0.58929*height))
path.closeSubpath()
path.move(to: CGPoint(x: 0.6912*width, y: 0.5*height))
path.addCurve(to: CGPoint(x: 0.49704*width, y: 0.32143*height), control1: CGPoint(x: 0.6912*width, y: 0.40143*height), control2: CGPoint(x: 0.60422*width, y: 0.32143*height))
path.addCurve(to: CGPoint(x: 0.30288*width, y: 0.5*height), control1: CGPoint(x: 0.38987*width, y: 0.32143*height), control2: CGPoint(x: 0.30288*width, y: 0.40143*height))
path.addCurve(to: CGPoint(x: 0.49704*width, y: 0.67857*height), control1: CGPoint(x: 0.30288*width, y: 0.59857*height), control2: CGPoint(x: 0.38987*width, y: 0.67857*height))
path.addCurve(to: CGPoint(x: 0.6912*width, y: 0.5*height), control1: CGPoint(x: 0.60422*width, y: 0.67857*height), control2: CGPoint(x: 0.6912*width, y: 0.59857*height))
path.closeSubpath()
return path
}
}

struct ContentView: View {

var scene: SKScene {
let scene = SKScene(fileNamed: "MyScene")!
scene.scaleMode = .resizeFill
return scene
}
var body: some View {

VStack (alignment: .center, spacing: 4) {
SpriteView(scene: scene)
.aspectRatio(contentMode: .fill)
.frame(width: 120, height: 120, alignment: .top)
.rotationEffect(.degrees(180))
//            .withAnimation(Animation.linear(duration: 1).repeatForever())
.clipShape(flowerhshape())

Text("Honor thy error as a hidden intention")
.font(.caption2)
.multilineTextAlignment(.center)
.fixedSize(horizontal: false, vertical: true)
.frame(alignment: .top)

}
.padding(.top, 12.0)
.frame(alignment: .bottom)
}

}
struct ContentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}