Arcgis silverlight3 layerlist

1、功能

     This sample includes a Map with one tiled map service layer and two dynamic map service layers.  A layer list shows the layer (service) name, a visibility check box, and a slider to adjust opacity.  Element binding in XAML is used to populate the ListBox contents and enable runtime interactivity between layers and UI elements in the layer list.   

     用个list显示不同图层，并可以显示图层名称，修改图层的透明度等，本例中，将一个服务（mxd文件）当成一个图层，和传统的图层（lyr）性质不同，传统图层的例子见SubLayer list

2、代码详解

     MainPage.axml中 

<UserControl x:Class="SilverlightApplication1.MainPage"
    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"
    mc:Ignorable="d"
    d:DesignHeight="300" d:DesignWidth="400" xmlns:esri="http://schemas.esri.com/arcgis/client/2009">

    <Grid x:Name="LayoutRoot" Background="White">

        <esri:Map x:Name="MyMap" Extent="-120,20,-90,60" >
            <esri:ArcGISTiledMapServiceLayer ID="Street Map" 
                    Url="http://server.arcgisonline.com/ArcGIS/rest/services/ESRI_ShadedRelief_World_2D/MapServer"/>
            <esri:ArcGISDynamicMapServiceLayer ID="State,City,Highway" Opacity="0.6" 
                    Url="http://sampleserver1.arcgisonline.com/ArcGIS/rest/services/Specialty/ESRI_StateCityHighway_USA/MapServer"/>
            <esri:ArcGISDynamicMapServiceLayer ID="California" Opacity="0.4"
                    Url="http://serverapps.esri.com/ArcGIS/rest/services/California/MapServer" />
        </esri:Map>

        <Border Background="#996495ED" BorderThickness="1" CornerRadius="5"
            HorizontalAlignment="Right"  VerticalAlignment="Top"
            Margin="20" Padding="5" BorderBrush="Black" >
            <ListBox x:Name="MyList" ItemsSource="{Binding ElementName=MyMap, Path=Layers}">
                <ListBox.ItemTemplate>
                    <DataTemplate>
                        <StackPanel Orientation="Horizontal">
                            <!--Layer visibility checkbox-->
                            <CheckBox IsChecked="{Binding Visible, Mode=TwoWay}" />
                            <!--Opacity slider-->
                            <Slider Margin="-5,0,0,0" Minimum="0" Maximum="1" Width="30" 
                                Value="{Binding Opacity, Mode=TwoWay}" Height="18" />
                            <!--Layer name-->
                            <TextBlock Text="{Binding ID, Mode=OneWay}" Margin="5,0,0,0" > 
                            <!-- Tooltip on hover-->
                                <ToolTipService.ToolTip>
                                    <StackPanel MaxWidth="400">
                                        <TextBlock FontWeight="Bold" Text="{Binding CopyrightText}" TextWrapping="Wrap" />
                                        <TextBlock Text="{Binding Description}" TextWrapping="Wrap" />
                                    </StackPanel>
                                </ToolTipService.ToolTip>
                            </TextBlock>
                        </StackPanel>
                    </DataTemplate>
                </ListBox.ItemTemplate>
            </ListBox>
        </Border>

    </Grid>
</UserControl>

<Border Background="#996495ED" BorderThickness="1" CornerRadius="5"

            HorizontalAlignment="Right"  VerticalAlignment="Top"

            Margin="20" Padding="5" BorderBrush="Black" >

设置ListBox的底色，边框，文字排版，位置等

 

<ListBox x:Name="MyList" ItemsSource="{Binding ElementName=MyMap, Path=Layers}">

设置ListBox的名称，数据源（MyMap的layers），绑定MyMap的Layers

 

<StackPanel Orientation="Horizontal"> 排版方向，横向（即下面的checkbox，Slider，TextBlock横向排列）

           <!--Layer visibility checkbox-->

           <CheckBox IsChecked="{Binding Visible, Mode=TwoWay}" />

           <!--Opacity slider-->

            <Slider Margin="-5,0,0,0" Minimum="0" Maximum="1" Width="30"

            Value="{Binding Opacity, Mode=TwoWay}" Height="18" />

            <!--Layer name-->

            <TextBlock Text="{Binding ID, Mode=OneWay}" Margin="5,0,0,0" >

 

以CheckBox为例，<CheckBox IsChecked="{Binding Visible, Mode=TwoWay}" />

Binding Visible：绑定地图图层的Visible属性，Mode=TwoWay，绑定模式解释如下：

You use the Mode property to specify the direction of the binding. The following enumeration list shows the available options for binding updates:

·         TwoWay updates the target property or the property whenever either the target property or the source property changes.

·         OneWay updates the target property only when the source property changes.

·         OneTime updates the target property only when the application starts or when the DataContext undergoes a change.

·         OneWayToSource updates the source property when the target property changes.

·         Default causes the default Mode value of target property to be used.

 

设置Tooltip on hover，当鼠标放到layerlist上的图层名称上时，显示内容

<ToolTipService.ToolTip>

   <StackPanel MaxWidth="400">排版模式，最宽400

   <TextBlock FontWeight="Bold" Text="{Binding CopyrightText}" TextWrapping="Wrap" /> TextBlock FontWeight设置，绑定图层的CopyrightText属性

   <TextBlock Text="{Binding Description}" TextWrapping="Wrap" />TextBlock设置，绑定图层的Description属性

   </StackPanel>

</ToolTipService.ToolTip>

3.、效果

http://help.arcgis.com/en/webapi/silverlight/samples/start.htm#LayerList