ImageTileSource Class

The class that should be implemented by classes that are tile sources for the ImageTileDataProvider.

Namespace: DevExpress.Xpf.Map

Assembly: DevExpress.Xpf.Map.v23.1.dll

NuGet Package: DevExpress.Wpf.Map

Declaration

C#

public abstract class ImageTileSource :
    MapDependencyObject,
    IImageTileSource,
    ITileItemSourceProvider

VB.NET

Public MustInherit Class ImageTileSource
    Inherits MapDependencyObject
    Implements IImageTileSource,
               ITileItemSourceProvider

Related API Members

The following members return ImageTileSource objects:

• ImageTileDataProvider.TileSource

Example

This example shows how to use an ImageTileDataProvider instance to generate map tiles.

• Create an ImageTileDataProvider object and assign it to the ImageLayer.DataProvider property.
• Create a class that inherits the ImageTileSource class.
• Implement the interface’s ImageTileSource.GetImageSource method that returns a bitmap for each tile based on its indices and the map control’s zoom level.
• Assign an instance of the class you developed to the ImageTileDataProvider.TileSource property.

View Example: https://github.com/DevExpress-Examples/dxmap-how-to-use-in-memory-image-tile-provider

Markup

XAML

<Window
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:DXMapInMemoryTileProvider"
        xmlns:dxm="http://schemas.devexpress.com/winfx/2008/xaml/map" 
        x:Class="DXMapInMemoryTileProvider.MainWindow"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <Grid>
        <dxm:MapControl>
            <dxm:ImageLayer x:Name="imageLayer"/>
        </dxm:MapControl>
    </Grid>
</Window>

Code-Behind

C#

using DevExpress.Xpf.Map;
using System;
using System.Globalization;
using System.Windows;
using System.Windows.Media;
using System.Windows.Media.Imaging;
namespace DXMapInMemoryTileProvider {
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window {
        public MainWindow() {
            InitializeComponent();
            ImageTileDataProvider tileDataProvider = new ImageTileDataProvider();
            tileDataProvider.TileSource = new SimpleTileGenerator();
            this.imageLayer.DataProvider = tileDataProvider;
        }
    }
    public class SimpleTileGenerator : ImageTileSource {
        Random rnd = new Random();
        public override string Name => nameof(SimpleTileGenerator);
        public override ImageSource GetImageSource(long x, long y, int level, Size size) {
            DrawingVisual drawingVisual = new DrawingVisual();
            using (DrawingContext drawingContext = drawingVisual.RenderOpen()) {
                FormattedText text = new FormattedText($"{x}:{y}:{level}", new CultureInfo("en-us"),
                                     FlowDirection.LeftToRight, new Typeface("Arial"), 14, Brushes.Black);
                drawingContext.DrawRectangle(new SolidColorBrush(Color.FromArgb(128, (byte)rnd.Next(255),
                                                                        (byte)rnd.Next(255), (byte)rnd.Next(255))), null, 
                                                                        new Rect(new Point(), size));
                drawingContext.DrawText(text, new Point(5, 5));
                drawingContext.Close();
            }
            RenderTargetBitmap bmp = new RenderTargetBitmap((int)size.Width, (int)size.Height, 96, 96, PixelFormats.Pbgra32);
            bmp.Render(drawingVisual);
            return bmp;
        }
        protected override MapDependencyObject CreateObject() {
            return new SimpleTileGenerator();
        }
    }
}

VB.NET

Imports DevExpress.Xpf.Map
Imports System
Imports System.Globalization
Imports System.Windows
Imports System.Windows.Media
Imports System.Windows.Media.Imaging
Namespace DXMapInMemoryTileProvider
    Public Partial Class MainWindow
        Inherits Window
        Public Sub New()
            InitializeComponent()
            Dim tileDataProvider As ImageTileDataProvider = New ImageTileDataProvider()
            tileDataProvider.TileSource = New SimpleTileGenerator()
            Me.imageLayer.DataProvider = tileDataProvider
        End Sub
    End Class
    Public Class SimpleTileGenerator
        Inherits ImageTileSource
        Private rnd As Random = New Random()
        Public Overrides ReadOnly Property Name As String
            Get
                Return NameOf(SimpleTileGenerator)
            End Get
        End Property
        Public Overrides Function GetImageSource(ByVal x As Long, ByVal y As Long, ByVal level As Integer, ByVal size As Size) As ImageSource
            Dim drawingVisual As DrawingVisual = New DrawingVisual()

            Using drawingContext As DrawingContext = drawingVisual.RenderOpen()
                Dim text As FormattedText = New FormattedText($"{x}:{y}:{level}", New CultureInfo("en-us"), FlowDirection.LeftToRight, New Typeface("Arial"), 14, Brushes.Black)
                drawingContext.DrawRectangle(New SolidColorBrush(Color.FromArgb(128, CByte(rnd.[Next](255)), CByte(rnd.[Next](255)), CByte(rnd.[Next](255)))), Nothing, New Rect(New Point(), size))
                drawingContext.DrawText(text, New Point(5, 5))
                drawingContext.Close()
            End Using
            Dim bmp As RenderTargetBitmap = New RenderTargetBitmap(CInt(size.Width), CInt(size.Height), 96, 96, PixelFormats.Pbgra32)
            bmp.Render(drawingVisual)
            Return bmp
        End Function

        Protected Overrides Function CreateObject() As MapDependencyObject
            Return New SimpleTileGenerator()
        End Function
    End Class
End Namespace

Inheritance

Object

DispatcherObject

DependencyObject

Freezable

MapDependencyObject

ImageTileSource