Manage operational layers

View inC++QMLView on GitHubSample viewer app

Add, remove, and reorder operational layers in a map.

screenshot

Use case

Operational layers display the primary content of the map and usually provide dynamic content for the user to interact with (as opposed to basemap layers that provide context).

The order of operational layers in a map determines the visual hierarchy of layers in the view. You can bring attention to a specific layer by rendering above other layers.

How to use the sample

When the app starts, a list displays the operational layers that are currently displayed in the map. Select the menu option on the list item to remove or reorder the layer. The map will be updated automatically.

The second list shows layers that have been removed from the map. Select the menu option on the list item to add it to the map.

How it works

  1. Get the operational layers LayerListModel from the map using map.operationalLayers.
  2. Subclass QSortFilterProxyModel so that the order in the view can be reversed. This is important when creating a table of contents so that the first layer in the map draws at the bottom of the list and the last layer in the map (which will render at the top) will draw on the top of the list.
  3. Set the LayerListModel as the source model on you sort proxy model.
  4. Create a QML ListView and set the model property to the reversed sort proxy model.
  5. Create a delegate that displays the layer name and a QML menu which provides options to add, remove, and reorder the layer.
  6. Add or remove layers using operationalLayers.append(layer) and operationalLayers.remove(layer) respectively.
  7. Move layers using operationalLayers.move(from, to).

Relevant API

  • ArcGISMapImageLayer
  • LayerListModel
  • LayerListModel.append
  • LayerListModel.move
  • LayerListModel.remove
  • Map

Tags

add, delete, layer, map, remove

Sample Code

ManageOperationalLayers.qmlManageOperationalLayers.qmlDrawOrderLayerListModel.cppDrawOrderLayerListModel.h
Use dark colors for code blocksCopy
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
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
// [WriteFile Name=ManageOperationalLayers, Category=Layers]
// [Legal]
// Copyright 2019 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.
// [Legal]

import QtQuick 2.6
import QtQuick.Controls 2.5
import QtQuick.Layouts 1.3
import Esri.ArcGISRuntime 100.15
import Esri.Samples 1.0

Rectangle {
    id: rootRectangle
    clip: true
    width: 800
    height: 600

    property var deletedLayerListModel: []
    property alias layerListModel: map.operationalLayers

    MapView {
        id: mapView
        anchors.fill: parent

        Component.onCompleted: {
            // Set the focus on MapView to initially enable keyboard navigation
            forceActiveFocus();
        }

        Map {
            id: map
            Basemap {
                initStyle: Enums.BasemapStyleArcGISTopographic
            }

            onLoadStatusChanged: {
                if (loadStatus !== Enums.LoadStatusLoaded)
                    return;

                // add layers to the map
                operationalLayers.append(elevationLayer);
                operationalLayers.append(censusLayer);
                operationalLayers.append(damageLayer);

                drawOrderModel.setLayerListModel(operationalLayers);
            }
        }
    }

    ArcGISMapImageLayer {
        id: elevationLayer
        url: "https://sampleserver5.arcgisonline.com/arcgis/rest/services/Elevation/WorldElevations/MapServer"
    }

    ArcGISMapImageLayer {
        id: censusLayer
        url: "https://sampleserver5.arcgisonline.com/arcgis/rest/services/Census/MapServer"
    }

    ArcGISMapImageLayer {
        id: damageLayer
        url: "https://sampleserver5.arcgisonline.com/arcgis/rest/services/DamageAssessment/MapServer"
    }

    // Declare a custom DrawOrderListModel. This is a QSortFilterProxyModel used to
    // "reverse" the order appearance so the top level layer displays at the top
    // of the list view instead of the bottom, which is the default behavior. This
    // will closer match the widely accepted standard table of contents UX where
    // the top level layer displays at the top of the view.
    DrawOrderListModel {
        id: drawOrderModel
    }

    Rectangle {
        anchors {
            fill: layerListColumn
            margins: -3
        }
        color: "#F5F5F5"
    }

    Column {
        id: layerListColumn
        anchors {
            top: parent.top
            left: parent.left
            margins: 8
        }
        spacing: 2

        Label {
            text: "Layers in map"
            visible: layersList.count > 0
            font {
                pixelSize: 14
                bold: true
            }
        }

        // Declare the ListView, which will display the list of files
        ListView {
            id: layersList
            height: contentHeight
            width: 200
            interactive: true
            clip: true
            visible: count > 0
            spacing: 5
            model: drawOrderModel
            delegate: Component {
                RowLayout {
                    width: parent.width
                    height: 40
                    spacing: 5

                    Label {
                        text: name
                        Layout.leftMargin: 5
                    }

                    Image {
                        Layout.alignment: Qt.AlignRight
                        Layout.preferredHeight: 25
                        Layout.preferredWidth: 25
                        source: "qrc:/Samples/Layers/ManageOperationalLayers/menu.png"

                        MouseArea {
                            anchors.fill: parent
                            onClicked: {
                                layersList.currentIndex = index;
                                menu.open();
                            }
                        }

                        Menu {
                            id: menu
                            width: 125

                            Column {
                                width: parent.width
                                spacing: 10

                                Label {
                                    id: moveUpLabel
                                    text: "  Move down  "
                                    visible: layersList.currentIndex + 1 !== layersList.count

                                    MouseArea {
                                        anchors.fill: parent
                                        onClicked: {
                                            menu.close();
                                            const  modelIndex = drawOrderModel.mappedIndex(index);
                                            layerListModel.move(modelIndex, modelIndex - 1);
                                        }
                                    }
                                }

                                Label {
                                    id: moveDownLabel
                                    text: "  Move up  "
                                    visible: layersList.currentIndex !== 0

                                    MouseArea {
                                        anchors.fill: parent
                                        onClicked: {
                                            menu.close();
                                            const  modelIndex = drawOrderModel.mappedIndex(index);
                                            layerListModel.move(modelIndex, modelIndex + 1);
                                        }
                                    }
                                }

                                Label {
                                    text: "  Remove  "

                                    MouseArea {
                                        anchors.fill: parent
                                        onClicked: {
                                            menu.close();
                                            const  modelIndex = drawOrderModel.mappedIndex(index);
                                            deletedLayerListModel.push(layerListModel.get(modelIndex));
                                            deletedLayersList.model = deletedLayerListModel
                                            layerListModel.remove(modelIndex);
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
            }
        }

        Label {
            text: "Deleted layers"
            visible: deletedLayersList.count > 0
            font {
                pixelSize: 14
                bold: true
            }
        }

        // Declare the ListView, which will display the list of files
        ListView {
            id: deletedLayersList
            height: contentHeight
            visible: deletedLayersList.count > 0
            width: 200
            interactive: true
            clip: true
            spacing: 5
            model: deletedLayerListModel

            delegate: Component {
                RowLayout {
                    width: parent.width
                    height: 40
                    spacing: 5

                    Label {
                        text: modelData.name
                        Layout.leftMargin: 5
                    }

                    Image {
                        Layout.alignment: Qt.AlignRight
                        Layout.preferredHeight: 25
                        Layout.preferredWidth: 25
                        source: "qrc:/Samples/Layers/ManageOperationalLayers/menu.png"

                        MouseArea {
                            anchors.fill: parent
                            onClicked: {
                                layersList.currentIndex = index;
                                addMenu.open();
                            }
                        }

                        // add menu
                        Menu {
                            id: addMenu
                            width: 125

                            Column {
                                width: parent.width
                                spacing: 10

                                Label {
                                    text: "  Add to map  "

                                    MouseArea {
                                        anchors.fill: parent
                                        onClicked: {
                                            addMenu.close();
                                            layerListModel.append(deletedLayersList.model[index])
                                            deletedLayerListModel.splice(index, 1);
                                            deletedLayersList.model = deletedLayerListModel;
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
            }
        }
    }
}

Your browser is no longer supported. Please upgrade your browser for the best experience. See our browser deprecation post for more details.