无法转换类型＆＃39; [String：String？]＆＃39;的值预期的参数类型＆＃39; [String：AnyObject？]＆＃39;

Question

我是Swift的新手，我遵循了本教程：http://www.raywenderlich.com/90971/introduction-mapkit-swift-tutorial关于MapKit。问题是我在这行代码上出错了

func mapItem() -> MKMapItem {
    let addressDict = [String(kABPersonAddressStreetKey): self.subtitle]
    let placemark = MKPlacemark(coordinate: self.coordinate, addressDictionary: addressDict)

    let mapItem = MKMapItem(placemark: placemark)
    mapItem.name = self.title

    return mapItem
}

错误在标题上描述。包含此行的方法是：

{{1}}

请帮忙。

Answer 1

您需要将subtitle转换为AnyObject，如下所示：

let addressDict = [String(kABPersonAddressStreetKey): self.subtitle as! AnyObject]

您的完整代码将是：

func mapItem() -> MKMapItem {
    let addressDict = [String(kABPersonAddressStreetKey): self.subtitle as! AnyObject]
    let placemark = MKPlacemark(coordinate: self.coordinate, addressDictionary: addressDict)

    let mapItem = MKMapItem(placemark: placemark)
    mapItem.name = self.title

    return mapItem
  }