Restrict zooming between specific scale ranges.
Use case
Data may only appear at a certain scale on a map, and may be visually lost if zooming too far in or out. Setting the minimum and maximum scales ensures the zoom extents are appropriately limited for the purposes of the map.
How to use the sample
Zoom in and out of the map. The zoom extents of the map are limited between the given minimum and maximum scales.
How it works
- Instantiate an
Map
object. - Set min and max scales of map with the
MinScale
andMaxScale
properties. - Display the map in a map view.
Relevant API
- Map
- Basemap
- MapView
- ViewPoint
Tags
area of interest, level of detail, maximum, minimum, scale, viewpoint
Sample Code
// 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.
using Android.App;
using Android.OS;
using Android.Widget;
using Esri.ArcGISRuntime.Geometry;
using Esri.ArcGISRuntime.Mapping;
using Esri.ArcGISRuntime.UI.Controls;
namespace ArcGISRuntime.Samples.SetMinMaxScale
{
[Activity (ConfigurationChanges=Android.Content.PM.ConfigChanges.Orientation | Android.Content.PM.ConfigChanges.ScreenSize)]
[ArcGISRuntime.Samples.Shared.Attributes.Sample(
name: "Set min & max scale",
category: "Map",
description: "Restrict zooming between specific scale ranges.",
instructions: "Zoom in and out of the map. The zoom extents of the map are limited between the given minimum and maximum scales.",
tags: new[] { "area of interest", "level of detail", "maximum", "minimum", "scale", "viewpoint" })]
public class SetMinMaxScale : Activity
{
// Hold a reference to the map view
private MapView _myMapView;
protected override void OnCreate(Bundle bundle)
{
base.OnCreate(bundle);
Title = "Set min & max scale";
// Create the UI, setup the control references and execute initialization
CreateLayout();
Initialize();
}
private void Initialize()
{
// Create new Map with Streets basemap
Map myMap = new Map(BasemapStyle.ArcGISStreets)
{
// Set the scale at which this layer can be viewed
// MinScale defines how far 'out' you can zoom where
// MaxScale defines how far 'in' you can zoom.
MinScale = 8000,
MaxScale = 2000
};
// Create central point where map is centered
MapPoint centralPoint = new MapPoint(-355453, 7548720, SpatialReferences.WebMercator);
// Create starting viewpoint
Viewpoint startingViewpoint = new Viewpoint(
centralPoint,
3000);
// Set starting viewpoint
myMap.InitialViewpoint = startingViewpoint;
// Set map to mapview
_myMapView.Map = myMap;
}
private void CreateLayout()
{
// Create a new vertical layout for the app
LinearLayout layout = new LinearLayout(this) { Orientation = Orientation.Vertical };
// Add the map view to the layout
_myMapView = new MapView(this);
layout.AddView(_myMapView);
// Show the layout in the app
SetContentView(layout);
}
}
}