MapControl.ZoomToFitLayerItems(IEnumerable<LayerBase>, Boolean, Double) Method

Zooms a map to fit vector items contained in the specified map layers. Allows you to specify whether to use an integer zoom level, and set the padding factor.

Namespace: DevExpress.Xpf.Map

Assembly: DevExpress.Xpf.Map.v25.1.dll

NuGet Package: DevExpress.Wpf.Map

Declaration

C#

public void ZoomToFitLayerItems(
    IEnumerable<LayerBase> layers,
    bool roundZoomLevel,
    double paddingFactor = 0.15
)

VB.NET

Public Sub ZoomToFitLayerItems(
    layers As IEnumerable(Of LayerBase),
    roundZoomLevel As Boolean,
    paddingFactor As Double = 0.15
)

Parameters

Name	Type	Description
layers	IEnumerable<LayerBase>	A collection of layers that contain items to be displayed on the map.
roundZoomLevel	Boolean	Specifies whether to round the zoom level value.

Optional Parameters

Name	Type	Default	Description
paddingFactor	Double	0.15	Specifies the size of the border around displayed map items.

Remarks

The ZoomToFitLayerItems method works as follows:

• Calculates a bounding box around map items contained in map layers.

  

• Zooms the map to fit the box.

  The padding factor is applied to the larger dimension of the bounding box that contains visible items.

  The following image shows an instance of a horizontal dimension that is larger than the vertical (“PF” means “Padding Factor” on images):

  

  When the vertical dimension is larger than the horizontal, the zoom appears as follows:

  

  Note that the padding factor is divided by two for each side of the region.

The following image shows a map with the padding factor parameter set to 0.3:

The following example shows how to zoom a map to display items contained in the specified map layers:

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:MapApp"
        xmlns:dxc="http://schemas.devexpress.com/winfx/2008/xaml/charts" 
        xmlns:dxm="http://schemas.devexpress.com/winfx/2008/xaml/map" 
        x:Class="MapApp.MainWindow"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800" Loaded="OnWindowLoaded">
    <Grid>

        <dxm:MapControl x:Name="mapControl">
            <dxm:VectorLayer x:Name="vectorLayer">
                <dxm:MapItemStorage x:Name="mapItemStorage">
                    <dxm:MapDot Location="51.30, 0.07" Size="20" Fill="Wheat"/>
                    <dxm:MapDot Location="52.31, 13.23" Size="20" Fill="Gold"/>
                    <dxm:MapDot Location="48.51, 2.21" Size="20" Fill="CadetBlue"/>
                    <dxm:MapDot Location="41.54, 12.3" Size="20" Fill="Red"/>
                    <dxm:MapDot Location="40.23, -3.43" Size="20" Fill="Green"/>
                </dxm:MapItemStorage>
            </dxm:VectorLayer>
        </dxm:MapControl>
    </Grid>
</Window>

C#

using DevExpress.Xpf.Map;
using System.Windows;

namespace MapApp {
    public partial class MainWindow : Window {

        private void OnWindowLoaded(object sender, RoutedEventArgs e) {
            mapControl.ZoomToFitLayerItems(layers: new LayerBase[] { vectorLayer }, roundZoomLevel: true, paddingFactor: 0.15);
        }

    }
}

VB.NET

Imports DevExpress.Xpf.Map

Namespace MapApp
    Public Partial Class MainWindow
        Inherits Window

        Private Sub OnWindowLoaded(ByVal sender As Object, ByVal e As RoutedEventArgs)
            mapControl.ZoomToFitLayerItems(layers:=New LayerBase() {vectorLayer}, roundZoomLevel:=True, paddingFactor:=0.15)
        End Sub
    End Class
End Namespace