SwiftUI：在 animation 期间更改 SF 符号的 symbolRenderingMode 会导致 EXC_BAD_INSTRUCTION

Question

I'm targeting iOS 16 for a project and found that changing an SF Symbol Image 's .symbolRenderingMode with an .animation applied sometimes causes a EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, subcode=0x0) crash with no meaningful stack trace or debug output. 删除.animation或保持.symbolRenderingMode常量可防止崩溃。 异常指向主应用程序文件的@main装饰器，这是提供的唯一堆栈跟踪：

这是堆栈跟踪中最顶层符号所指向的汇编代码的尾部：

我在这里做错了什么还是这是一个 SDK 错误？ 我希望能够在模式之间进行转换，但如果必须的话，我可以只.multicolor - 只是无法弄清楚为什么会发生这种情况。 以下是我的最小可重现示例：

import SwiftUI

struct ContentView: View {
    @State var mode = 0
    var modeName: String {
        mode == 0 ? "Palette" : mode == 1 ? "Multicolor" : "Monochrome"
    }
    var nextModeName: String {
        mode == 0 ? "Multicolor" : mode == 1 ? "Monochrome" : "Palette"
    }

    var body: some View {
        VStack {
            Image(systemName: "list.bullet.clipboard")
                .font(.system(size: 50))
                .symbolRenderingMode(mode == 0 ? .palette : mode == 1 ? .multicolor : .monochrome)
                .foregroundStyle(.primary, .secondary)
                .padding()
        
            Text("Current SRM: \(modeName)")
            Button("Tap to set SRM to: \(nextModeName)", action: {mode = mode == 2 ? 0 : mode + 1})
        }
        // Commenting out this line stops crashes
        .animation(.linear, value: mode)
    }
}

Answer 1

好像是个bug...

我使用枚举重新创建了项目，但我遇到了同样的崩溃。

在更改了几次monochrome的 position 后，我无法重现它。

import SwiftUI

@available(iOS 15.0, *)
struct RenderSampleView: View {
    @State var mode: RenderSamples = .palette
    
    var next: RenderSamples{
        RenderSamples(rawValue: mode == RenderSamples.allCases.last ? 0 : mode.rawValue + 1)!
    }
    
    var body: some View {
        VStack {
            Image(systemName: "list.bullet.clipboard")
                .font(.system(size: 50))
                .symbolRenderingMode(mode.mode)
                .foregroundStyle(.primary, .secondary)
                .padding()
            
            Text("Current SRM: \(mode.name)")
            Button("Tap to set SRM to: \(next.name)", action: {
                mode = next
            })
        }
        // Commenting out this line stops crashes
        .animation(.linear, value: mode)
    }
}
@available(iOS 15.0, *)
enum RenderSamples: Int, CaseIterable{
    case palette
    case monochrome // Alternate
    case multicolor
    //case monochrome //Alternate
    var name: String{
        switch self{
        case .palette:
            return "Palette"
        case .multicolor:
            return "Multicolor"
        case .monochrome:
            return "Monochrome"
        }
    }
    var mode: SymbolRenderingMode{
        switch self{
        case .palette:
            return .palette
        case .multicolor:
            return .multicolor
        case .monochrome:
            return .monochrome
        }
    }
    
}



@available(iOS 15.0, *)
struct RenderSampleView_Previews: PreviewProvider {
    static var previews: some View {
        RenderSampleView()
    }
}