Unique value renderer

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
//
// Copyright 2016 Esri.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

import UIKit
import ArcGIS

/// A view controller that manages the interface of the Unique Value Renderer
/// sample.
class UniqueValueRendererViewController: UIViewController {
    /// The map view managed by the view controller.
    @IBOutlet var mapView: AGSMapView! {
        didSet {
            // assign map to the map view
            mapView.map = makeMap()

            // set initial viewpoint
            let center = AGSPoint(x: -12966000.5, y: 4441498.5, spatialReference: .webMercator())
            mapView.setViewpoint(AGSViewpoint(center: center, scale: 4e7))
        }
    }

    /// Creates a map with a feature layer configured with a unique value
    /// renderer.
    ///
    /// - Returns: A new `AGSMap` object.
    func makeMap() -> AGSMap {
        // instantiate map with basemap
        let map = AGSMap(basemapStyle: .arcGISTopographic)

        // create feature layer
        let featureTable = AGSServiceFeatureTable(url: URL(string: "https://sampleserver6.arcgisonline.com/arcgis/rest/services/Census/MapServer/3")!)
        let featureLayer = AGSFeatureLayer(featureTable: featureTable)

        // make unique value renderer and assign it to the feature layer
        featureLayer.renderer = makeUniqueValueRenderer()

        // add the layer to the map as operational layer
        map.operationalLayers.add(featureLayer)

        return map
    }

    /// Creates a unique value renderer configured to render California as red,
    /// Arizona as green, and Nevada as blue.
    ///
    /// - Returns: A new `AGSUniqueValueRenderer` object.
    func makeUniqueValueRenderer() -> AGSUniqueValueRenderer {
        // instantiate a new unique value renderer
        let renderer = AGSUniqueValueRenderer()

        // set the field to use for the unique values
        // You can add multiple fields to be used for the renderer in the form of a list, in this case we are only adding a single field
        renderer.fieldNames = ["STATE_ABBR"]

        // create symbols to be used in the renderer
        let defaultSymbol = AGSSimpleFillSymbol(style: .null, color: .clear, outline: AGSSimpleLineSymbol(style: .solid, color: .gray, width: 2))
        let californiaSymbol = AGSSimpleFillSymbol(style: .solid, color: .red, outline: AGSSimpleLineSymbol(style: .solid, color: .red, width: 2))
        let arizonaSymbol = AGSSimpleFillSymbol(style: .solid, color: .green, outline: AGSSimpleLineSymbol(style: .solid, color: .green, width: 2))
        let nevadaSymbol = AGSSimpleFillSymbol(style: .solid, color: .blue, outline: AGSSimpleLineSymbol(style: .solid, color: .blue, width: 2))

        // set the default symbol
        renderer.defaultSymbol = defaultSymbol
        renderer.defaultLabel = "Other"

        // create unique values
        let californiaValue = AGSUniqueValue(description: "State of California", label: "California", symbol: californiaSymbol, values: ["CA"])
        let arizonaValue = AGSUniqueValue(description: "State of Arizona", label: "Arizona", symbol: arizonaSymbol, values: ["AZ"])
        let nevadaValue = AGSUniqueValue(description: "State of Nevada", label: "Nevada", symbol: nevadaSymbol, values: ["NV"])

        // add the values to the renderer
        renderer.uniqueValues.append(contentsOf: [californiaValue, arizonaValue, nevadaValue])

        return renderer
    }

    // MARK: UIViewController

    override func viewDidLoad() {
        super.viewDidLoad()

        // add the source code button item to the right of navigation bar
        (self.navigationItem.rightBarButtonItem as! SourceCodeBarButtonItem).filenames = ["UniqueValueRendererViewController"]
    }
}