Show magnifier

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Tap and hold on a map to show a magnifier.

Image of show magnifier sample

Use case

Due to the limited screen size of some mobile devices, it may be difficult to identify individual features on a map where there is a high density of information, or the scale is very small. This can be the case when a mobile device is used for navigation, and the user wishes to magnify a particular area to better identify a road intersection.

How to use the sample

Tap and hold on the map to show a magnifier, then drag across the map to move the magnifier. You can also pan the map while holding the magnifier, by dragging the magnifier to the edge of the map.

How it works

Create a new MapView, and set a Map on it.
Enable or diabled the magnifier using magnifierDisabled(_:) modifier. Enabling this will set the magnifier to be shown on the Map when the user performs a long press gesture. Note: The magnifier is enabled by default.
Optionally, use the magnifierEdgePanningDisabled(_:) modifier to allow the map to be panned automatically when the magnifier gets near the edge of the Map.

Relevant API

Map
MapView
MapView.magnifierDisabled(_:)
MapView.magnifierEdgePanningDisabled(_:)

Sample Code

ShowMagnifierView.swift
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// Copyright 2025 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 ShowMagnifierView: View {
    /// A map with a "World Topographic Map" tiled layer.
    @State private var map = Map(basemapStyle: .arcGISTopographic)

    /// A Boolean value indicating if the magnifier is enabled.
    @State private var magnifierIsEnabled = true

    var body: some View {
        MapView(map: map)
            // Enable/disable magnifier.
            .magnifierDisabled(!magnifierIsEnabled)
            // Enable/disable panning as the magnifier approaches a map edge.
            .magnifierEdgePanningDisabled(false)
            .toolbar {
                ToolbarItem(placement: .bottomBar) {
                    // Button to toggle whether the magnifier is enabled.
                    Button {
                        magnifierIsEnabled.toggle()
                    } label: {
                        Image(
                            systemName: magnifierIsEnabled ? "magnifyingglass.circle.fill" : "magnifyingglass.circle"
                        )
                    }
                }
            }
    }
}

#Preview {
    ShowMagnifierView()
}