Question

我使用的是google-maps-sdk，我在同一个UITableView中有一个GMSMapView和一个viewcontroller。我将autocomplete search结果放在tableview中，我想将地图移动到用户选择的单元格所代表的位置。我正在尝试使用didSelectRowAtIndexPath方法更新地图，但我一直收到＆＃34;未解包的nil可选错误。＆＃34;这非常令人困惑，因为我确实将可选项分配给我尝试打开它的上面一行的值。

我将self.mapview分配给相机时出错。任何帮助/想法将不胜感激。谢谢！

ViewDidLoad方法

override func viewDidLoad() {
        super.viewDidLoad()

        self.tableView.dataSource = self
        self.tableView.delegate = self

        self.resultSearchController = ({
            let controller = UISearchController(searchResultsController: nil)
            controller.searchResultsUpdater = self
            controller.dimsBackgroundDuringPresentation = false
            controller.searchBar.sizeToFit()
            controller.hidesNavigationBarDuringPresentation = false
            self.navigationItem.titleView = controller.searchBar
            //self.tableView.tableHeaderView = controller.searchBar
            return controller
        })()

        placesClient = GMSPlacesClient()

        var camera: GMSCameraPosition = GMSCameraPosition.cameraWithLatitude(-33.86,
            longitude: 151.20, zoom: 6)
        self.mapSubView.camera = camera
        self.mapSubView = GMSMapView.mapWithFrame(CGRectZero, camera: camera)
        self.mapSubView.myLocationEnabled = true



        var marker = GMSMarker()
        marker.position = CLLocationCoordinate2DMake(-33.86, 151.20)
        marker.title = "Sydney"
        marker.snippet = "Australia"
        marker.map = mapSubView


    }

didSelectRowAtIndexPath方法

  func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
    tableView.deselectRowAtIndexPath(indexPath, animated: true)
    view.sendSubviewToBack(self.tableView)
    var result = searchResults[indexPath.row]
    var camera = GMSCameraPosition.cameraWithLatitude(42.37, longitude: -71.109734, zoom: 16)
    self.mapSubView.camera = camera
    self.mapSubView = GMSMapView.mapWithFrame(self.mapSubView.bounds, camera: self.mapSubView.camera)

}

Answer 1

现在我清楚地知道你的问题所在：

if let mapSubView2 = self.mapSubView {
 mapSubView2.camera = camera
 self.mapSubView = mapView
}

这种情况永远不会满足，这就是为什么你的mapSubView是零的。为什么？我认为你打算写一些像

这样的东西

if let mapSubView2 = mapView {
 mapSubView2.camera = camera
 self.mapSubView = mapSubView2
}

但是你可以跳过所有这些检查并直接分配mapSubView如下

self.mapSubView = GMSMapView.mapWithFrame(CGRectZero, camera: camera)
self.mapSubView.myLocationEnabled = true

在didselectrowatindexpath中更新谷歌地图相机时展开nil可选

1 个答案: