我已经创建了下面的委托，无论我尝试什么，当调用reconcile()函数时，selectedTransaction都返回为nil。我将介绍委托模式，因为我有不同的模式和数据需求等。

class MatchReconciliationViewState: ReconciliationDelegate {
    var selectedTransaction: Transaction?
    let statementLine: StatementLine
    
    init(selectedTransaction: Transaction? = nil, statementLine: StatementLine) {
        self.selectedTransaction = selectedTransaction
        self.statementLine = statementLine
    }
    
    func canReconcile() -> Bool {
        return nil != selectedTransaction
    }
    
    func reconcile() {
        print("reconcile: \(String(describing: selectedTransaction))")
        guard let selectedTransaction = selectedTransaction else { return }
        
        ReconciliationFunctions.match(statementLine: statementLine, toTransaction: selectedTransaction)
    }
}

子视图是一个简单的列表，它选择列表中的对象（这部分工作）。onChange中的这些值打印显示我实际上持有数据（onChange发生在子视图中）：

.onChange(of: selectedTransaction) { newValue in
    print("onChange: \(String(describing: selectedTransaction))")
    reconciliationDelegate.selectedTransaction = newValue
    parentState.canReconcile = reconciliationDelegate.canReconcile()
    print("onChangeDelegate: \(String(describing: reconciliationDelegate.selectedTransaction))")
}

但是当我开始使用它时，selectedTransaction的值总是nil（从父视图上的按钮触发）：

private func reconcileStatementLine() {
    print("delegate: \(String(describing: state.reconciliationDeleage))")
    state.reconciliationDeleage?.reconcile()
//        persistence.commit()
//        presentationMode.wrappedValue.dismiss()
}

协议：

public protocol ReconciliationDelegate: AnyObject {
    func canReconcile() -> Bool
    func reconcile()
}

浏览次数：

@StateObject var state: ReconciliationViewState

var body: some View {
    Button(action: reconcileStatementLine) {
        Text("Reconcile")
    }
}

private func reconcileStatementLine() {
    print("delegate: \(String(describing: state.reconciliationDeleage))")
    state.reconciliationDeleage?.reconcile()
//        persistence.commit()
//        presentationMode.wrappedValue.dismiss()
}

ReconciliationViewState保存这样的值（有@Published属性，但与问题无关）：

class ReconciliationViewState: ObservableObject {
    var reconciliationDeleage: ReconciliationDelegate? = nil
}

我错过了什么，还是不明白？