Synchronize offline edits with a feature service.
Use case
A survey worker who works in an area without an internet connection could take a geodatabase of survey features offline at their office, make edits and add new features to the offline geodatabase in the field, and sync the updates with the online feature service after returning to the office.
How to use the sample
Pan and zoom to position the red rectangle around the area you want to take offline. Tap "Generate Geodatabase" to take the area offline. When complete, the map will update to only show the offline area. To edit features, tap on a feature to select it and tap again anywhere else on the map to move the selected feature to the tapped location. To sync the edits with the feature service, tap the "Sync Geodatabase" button.
How it works
- Create a
GeodatabaseSyncTask
from a URL to a feature service. - Create the default
GenerateGeodatabaseParameters
usingGeodatabaseSyncTask.makeDefaultGenerateGeodatabaseParameters(extent:)
, passing in anEnvelope
extent. - Create a
GenerateGeodatabaseJob
usingGeodatabaseSyncTask.makeGenerateGeodatabaseJob(parameters:downloadFileURL:)
, passing in the parameters and a path to where the geodatabase should be downloaded locally. - Start the job and get the result
Geodatabase
. - To enable editing, load the geodatabase and get its feature tables. Create feature layers from the feature tables and add them to the map's operational layers collection.
- Create the default
SyncGeodatabaseParameters
usingGeodatabaseSyncTask.makeDefaultSyncGeodatabaseParameters(geodatabase:syncDirection:)
. - Create a
SyncGeodatabaseJob
fromGeodatabaseSyncTask
usingmakeSyncGeodatabaseJob(parameters:geodatabase:)
passing in the parameters and geodatabase as arguments. - Start the sync job to synchronize the edits.
Relevant API
- FeatureLayer
- FeatureTable
- GenerateGeodatabaseJob
- GenerateGeodatabaseParameters
- GeodatabaseSyncTask
- SyncGeodatabaseJob
- SyncGeodatabaseParameters
- SyncLayerOption
Offline data
This sample uses a San Francisco offline basemap tile package.
About the data
The basemap uses an offline tile package of San Francisco. The online feature service has features with wildfire information.
Tags
feature service, geodatabase, offline, synchronize
Sample Code
// Copyright 2024 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
//
// https://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 ArcGIS
import SwiftUI
struct EditAndSyncFeaturesWithFeatureServiceView: View {
/// The view model for the sample.
@StateObject private var model = Model()
/// The asynchronous action currently being preformed.
@State private var selectedAction: AsyncAction? = .setUpMap
/// The text describing the status of the sample.
@State private var statusText = ""
/// The error shown in the error alert.
@State private var error: Error?
var body: some View {
GeometryReader { geometryProxy in
MapViewReader { mapViewProxy in
MapView(map: model.map)
.interactionModes(
// Disables the map when a geodatabase has been generated.
model.geodatabase == nil ? [.all] : []
)
.onSingleTapGesture { screenPoint, mapPoint in
guard model.geodatabase != nil else { return }
selectedAction = model.selectedFeature == nil
? .selectFeature(screenPoint: screenPoint)
: .moveSelectedFeature(mapPoint: mapPoint)
}
.task(id: selectedAction) {
// Performs the selected action.
guard let action = selectedAction else { return }
do {
switch action {
case .setUpMap:
statusText = "Loading feature layers…"
try await model.setUpMap()
statusText = action.completionMessage
case .generateGeodatabase:
// Creates an envelope from the area of interest.
let viewRect = geometryProxy.frame(in: .local).inset(
by: UIEdgeInsets(
top: 20,
left: geometryProxy.safeAreaInsets.leading + 20,
bottom: 44,
right: -geometryProxy.safeAreaInsets.trailing + 20
)
)
guard let extent = mapViewProxy.envelope(
fromViewRect: viewRect
) else { return }
// Generates the geodatabase using the envelope.
try await model.generateGeodatabase(extent: extent)
statusText = action.completionMessage
case .selectFeature(let screenPoint):
// Identifies and selects a feature at the tapped screen point.
let identifyLayerResults = try await mapViewProxy.identifyLayers(
screenPoint: screenPoint,
tolerance: 22,
maximumResultsPerLayer: 1
)
model.selectFeature(identifyLayerResults: identifyLayerResults)
if model.selectedFeature != nil {
statusText = action.completionMessage
}
case .moveSelectedFeature(mapPoint: let mapPoint):
try await model.moveSelectedFeature(point: mapPoint)
statusText = action.completionMessage
case .sync:
try await model.syncGeodatabase()
statusText = action.completionMessage
case .cancelJob:
await model.cancelJob()
statusText = action.completionMessage
case .reset:
await model.reset()
await mapViewProxy.setViewpoint(model.map.initialViewpoint!)
selectedAction = .setUpMap
return
}
} catch {
self.error = error
}
selectedAction = nil
}
.errorAlert(presentingError: $error)
}
}
.overlay(alignment: .top) {
VStack {
Text(statusText)
.multilineTextAlignment(.center)
.frame(maxWidth: .infinity, alignment: .center)
.padding(8)
.background(.regularMaterial, ignoresSafeAreaEdges: .horizontal)
// The red rectangle representing the extent of data to include in the geodatabase.
Rectangle()
.stroke(.red, lineWidth: 2)
.padding(EdgeInsets(top: 20, leading: 20, bottom: 44, trailing: 20))
.opacity(model.geodatabase == nil ? 1 : 0)
}
}
.toolbar {
ToolbarItemGroup(placement: .bottomBar) {
Button("Reset") {
selectedAction = .reset
}
.disabled(model.geodatabase == nil)
if model.geodatabase == nil {
Button("Generate Geodatabase") {
selectedAction = .generateGeodatabase
}
} else {
Button("Sync Geodatabase") {
selectedAction = .sync
}
.disabled(!(model.geodatabase?.hasLocalEdits ?? false))
}
}
}
.disabled(selectedAction != nil)
.overlay(alignment: .center) {
// Shows a progress view when there is a job currently running.
if let progress = model.currentJob?.progress {
VStack {
Text(selectedAction == .generateGeodatabase
? "Creating geodatabase…"
: "Syncing geodatabase…"
)
.padding(.bottom)
ProgressView(progress)
.frame(maxWidth: 180)
Button("Cancel") {
selectedAction = .cancelJob
}
.disabled(selectedAction == .cancelJob)
}
.padding()
.background(.ultraThickMaterial)
.cornerRadius(10)
.shadow(radius: 50)
}
}
.onDisappear {
// Cancels any running jobs when the sample is exited.
Task { await model.cancelJob() }
}
}
}
/// An asynchronous action associated with the sample.
private enum AsyncAction: Equatable {
/// Sets up the map for the sample.
case setUpMap
/// Generates a geodatabase from the current area of interest.
case generateGeodatabase
/// Identifies and selects a feature identified at a given screen point.
case selectFeature(screenPoint: CGPoint)
/// Moves the selected feature to a given map point.
case moveSelectedFeature(mapPoint: Point)
/// Synchronizes the geodatabase and the feature service.
case sync
/// Cancels the current job.
case cancelJob
/// Resets the sample.
case reset
/// The message to display when the action successfully completes.
var completionMessage: String {
switch self {
case .setUpMap: "Tap the generate button to take the area offline."
case .generateGeodatabase: "Tap on a feature to edit."
case .selectFeature: "Tap on the map to move the feature."
case .moveSelectedFeature: "Tap the sync button to sync the edits."
case .sync: "Geodatabase sync successful."
case .cancelJob: "Job canceled."
default: "Unknown"
}
}
}