问题

I have a list with 4 objects of places that I query from my Realm database.

Optional(Results<Place> <0x7feaaea447c0> (
    [0] Place {
        name = Daniel Webster Highway;
        country = United States;
        lat = 42.72073329999999;
        lon = -71.44301460000001;
    },
    [1] Place {
        name = District Avenue;
        country = United States;
        lat = 42.48354969999999;
        lon = -71.2102486;
    },
    [2] Place {
        name = Gorham Street;
        country = United States;
        lat = 42.62137479999999;
        lon = -71.30538779999999;
    },
    [3] Place {
        name = Route de HHF;
        country = Haiti;
        lat = 18.6401311;
        lon = -74.1203939;
    }
))

I'm trying to hide the selected one.

Ex. When I click on Daniel Webster Highway, I don't want that to show on my list.

How would one go above and do that in Swift 4 ?

Code

//
//  PlaceDetailVC.swift
//  Memorable Places
//
//

import UIKit
import CoreLocation
import RealmSwift

class PlaceDetailVC: UIViewController, UITableViewDelegate, UITableViewDataSource {

    @IBOutlet weak var address: UILabel!
    @IBOutlet weak var placesTable: UITableView!

    var selectedPlace : Place = Place()
    var selectedTrip : Trip = Trip()

    var distances = [ String ]()
    var places : Results<Place>?

    override func viewDidLoad() {
        super.viewDidLoad()

        address.text = selectedPlace.name

        //register xib file
        placesTable.register(UINib(nibName: "PlaceDetailCell", bundle: nil), forCellReuseIdentifier: "customPlaceDetailCell")

    }

    override func viewDidAppear(_ animated: Bool) {

        load()

        if selectedPlace != nil && places != nil {

            for i in 0..<places!.count {

                let latitude = Double(places![i].lat)
                let longitude = Double(places![i].lon)

                let currentLatitude = Double(selectedPlace.lat)
                let currentLongitude = Double(selectedPlace.lon)

                //print(latitude,longitude,currentLatitude,currentLongitude)

                let coordinate = CLLocation(latitude: latitude, longitude: longitude)
                let currentCoordinate = CLLocation(latitude: currentLatitude, longitude: currentLongitude)

                let distanceInMeters = coordinate.distance(from: currentCoordinate) // result is in meters
                let distanceInMiles = distanceInMeters/1609.344

                distances.append(String(format: "%.2f", distanceInMiles))

            }

        }
    }

    // ---------------------------------------------------------------------------------------------------------
    //MARK - CRUD functions


    //Read
    func load() {
        places  = selectedTrip.places.sorted(byKeyPath: "name", ascending: true)
        //print(places,"<<<")
        placesTable.reloadData()

    }


    // ---------------------------------------------------------------------------------------------------------
    //MARK - Table View Datasource

    func numberOfSections(in tableView: UITableView) -> Int {
        return 1
    }

    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return places?.count ?? 0
    }

    func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
        return 70
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

        let cell = tableView.dequeueReusableCell(withIdentifier: "customPlaceDetailCell", for: indexPath)
         as! CustomPlaceDetailCell

        if selectedPlace.name != nil {

            cell.address.text = (places![indexPath.row]["name"] as! String)
            cell.distance.text = distances[indexPath.row]

        }

        return cell
    }

    // ---------------------------------------------------------------------------------------------------------
    //MARK - Table View Delegate

    func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
        return true
    }

    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        activePlace = indexPath.row
    }



}

回答1:

You could pass the index of the selected row from placesVC to your PlaceDetailVC and in

func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {

    if indexPath.row == passedIndex {
        return 0
    }

    return 70
}

set the cell height to 0 to hide the cell.

回答2:

var distances = [ String ]()
var places : Results<Place>?

Then in tableView(_:cellForRow:)

cell.address.text = (places![indexPath.row]["name"] as! String)
cell.distance.text = distances[indexPath.row]

Just don't do that. These info need to be synchronized.

Instead, use another class/struct, or an extension which will hold the distance and the place.

var array: [PlaceModel]
struct PlaceModel {
    let place: Place
    let distance: Double //You can use String, but that's bad habit
    //Might want to add the "image link" also?
}

In load():

array.removeAll()
let tempPlaces = selectedTrip.places.sorted(byKeyPath: "name", ascending: true)
for aPlace in tempPlaces {
    let distance = //Calculate distance for aPlace
    array.append(PlaceModel(place: aPlace, distance: distance)
}

Now, in tableView(_:cellForRow:):

let aPlaceModel = array[indexPath.row]
if activePlace == indexPath {
    let cell = tableView.dequeue...
    //Use cellWithImage for that place
    return cell
} else {
    let cell = tableView.dequeue...
    cell.address.text = aPlaceModel.place.name
    cell.distance.text = aPlaceModel.distance
    return cell
}

And keep that logic wherever you want, if the heightForRow if needed (if you want for instance that all your images be at 80pt but the rest at 44pts, etc.

In tableView(_:didSelectRowAt:), add tableView.reloadData(), or better tableView.reloadRows(at: [indexPath] with: .automatic)

NB: Code not tested, might not compile, but you should get the idea.

来源：https://stackoverflow.com/questions/53174828/hide-selected-cell-from-the-table-swift4

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