ios – Easy methods to fetch information with dynamic filter and replace in SwiftData

I’m very new to SwiftData and I’ve been confused for this subject. I searched nearly all of the posts/ movies /Udemy programs however the instances are all the time completely different from mine. I attempted Question/Fetch and likewise with GPT however nonetheless no solutions but

I’m making a PDF reader, for every web page enable consumer to make drawings (with a canvas above the web page). The issue is within the canvasView, I can’t fetch the particular canvas information for sure web page. (pdfFile and Web page I saved in an environmentObject).
Please advise

struct CanvasView: UIViewRepresentable {
@EnvironmentObject var thisContentModel: envContentModel
@Setting(.modelContext) personal var modelContext: ModelContext
//var currentFile: ContentModel
//var currentPage: Int
@Binding var pdfPageBounds: CGRect
@Binding var pdfViewScale: CGFloat

@Question personal var pdfDrawingList: [PDFDrawing]
@State personal var drawing = PKDrawing()

var thisPageDrawing: PDFDrawing {
    if let existedDrawing = pdfDrawingList.first(the place: { $0.file == thisContentModel.contentModel && $0.web page == thisContentModel.currentPage }) {
        return existedDrawing
    } else {
       
        let newDrawing = PDFDrawing(web page: thisContentModel.currentPage, drawingData: drawing.dataRepresentation(), file: thisContentModel.contentModel)
        modelContext.insert(newDrawing)
        return newDrawing
    }
}

func makeUIView(context: Context) -> PKCanvasView {
    let canvasView = PKCanvasView()
    canvasView.drawingPolicy = .anyInput
    canvasView.delegate = context.coordinator
    canvasView.device = PKInkingTool(.pen, coloration: .black, width: 5)
    canvasView.backgroundColor = .clear
    canvasView.isOpaque = false
    canvasView.becomeFirstResponder()
    // 将 drawingData 转换为 PKDrawing
       if let drawingFromData = attempt? PKDrawing(information: thisPageDrawing.drawingData) {
           canvasView.drawing = drawingFromData
       } else {
           canvasView.drawing = PKDrawing()
       }
    
    return canvasView
    
}

The PDFDrawings information mannequin as under:

@Mannequin
class PDFDrawing: ObservableObject {
    //@Attribute var fileID: UUID
    @Attribute var web page: Int
    @Attribute var drawingData: Knowledge
    
    @Relationship
    var file: ContentModel

    init(web page: Int, drawingData: Knowledge, file: ContentModel) {
        self.web page = web page
        self.drawingData = drawingData
        self.file = file
        //self.fileID = file.id
    }
}