CacheOptions.KeepInterval Property

Specifies the time interval after which tile images are updated from a map data provider.

Namespace: DevExpress.Xpf.Map

Assembly: DevExpress.Xpf.Map.v21.2.dll

NuGet Package: DevExpress.Wpf.Map

Declaration

C#

public TimeSpan KeepInterval { get; set; }

VB.NET

Public Property KeepInterval As TimeSpan

Property Value

Type	Description
TimeSpan	A TimeSpan structure that is the keep interval for a local cache.

Property Paths

You can access this nested property as listed below:

Object Type	Path to KeepInterval
MapControl	.CacheOptions .KeepInterval
MapDataProviderBase	.CacheOptions .KeepInterval

Example

This example illustrates what actions should be executed to customize the local cache of a map control.

The local cache allows you to save internet resources and significantly increases map performance by loading saved map tiles from the local directory.

To enable the map cache, it is necessary to assign the MapControl.CacheOptions property to the CacheOptions object and specify the directory to which the loaded map tiles will be saved using the CacheOptions.Directory property. It is also necessary to specify the time interval after which map tile images will be updated from a map data provider via the CacheOptions.KeepInterval property.

In this example tile images of a map are loaded from the openstreetmap.org resource.

View Example

MainWindow.xaml

<Window x:Class="MapCacheOptions.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:dxm="http://schemas.devexpress.com/winfx/2008/xaml/map"
        Title="MainWindow" Height="350" Width="525" >
    <Grid>
        <dxm:MapControl>
            <dxm:MapControl.CacheOptions>
                <dxm:CacheOptions Directory="C://MapTiles" KeepInterval="01:00:00"/>
            </dxm:MapControl.CacheOptions>
            <dxm:ImageTilesLayer >
                <dxm:ImageTilesLayer.DataProvider>
                    <dxm:OpenStreetMapDataProvider Kind="Road" />
                </dxm:ImageTilesLayer.DataProvider>
            </dxm:ImageTilesLayer>
        </dxm:MapControl>
    </Grid>
</Window>