调试 Swift / Objective-C

Question

我有一个名为 PaymentInfo 的 Parse 子类，定义为

class PaymentInfo: PFObject, PFSubclassing {

override class func initialize() {
    var once: dispatch_once_t = 0;
    dispatch_once(&once) {
        self.registerSubclass()
    }
}

static func parseClassName() -> String {
    return "PaymentInfo"
}

@NSManaged var paymentUserID: String!
@NSManaged var walletID: String!

convenience init(userID: String, walletID: String) {
    self.init()
    self.paymentUserID = userID
    self.walletID = walletID
}

}

在 lldb 中调试时，我得到一个实例并查看成员

(lldb) expr self.paymentInfo
(Nestor.PaymentInfo!) $R0 = 0x00007f9e15805740 {
  Parse.PFObject = {...}
}
(lldb) po $R0
<PaymentInfo: 0x7f9e15805740, objectId: 2gKS5LhD35, localId: (null)> {
    paymentUserID = 10104705;
    walletID = 10104706;
}

到目前为止一切顺利。但我不明白的是：

(lldb) expr $R0.paymentUserID
2015-12-17 16:09:17.432 Nestor[3474:482967] -[PFObject paymentUserID]: unrecognized selector sent to instance 0x7f9e15805740
error: Execution was interrupted, reason: internal ObjC exception breakpoint(-3)..
The process has been returned to the state before expression evaluation.

显然，lldb 知道 $R0 是（合格）类型 Nestor.PaymentInfo 的 IUO！但是当询问 paymentUserID 属性时，信息丢失了......为什么？

还是我错过了什么？

谢谢

B

Answer 1

这必须在 Xcode 7.2 中修复，因为它适用于我使用您的课程。