topic Re: Find & query in ArcGIS API for Silverlight Questions

Find & query

TonyAlmeida — Mon, 19 Jul 2010 20:35:58 GMT

I would like to query a layer, but also incorporate a find. Just like the "Find" and "Query attribute" examples but into one. Anyone have a simple one that's put together that you can share please?

Re: Find & query

TonyAlmeida — Tue, 20 Jul 2010 16:16:56 GMT

How I can i modify the "Attribute Query" to instead of a drop down and select to just a search, input box. I would like to keep the "Attribute Query" functionality except make it into a search?

Re: Find & query

dotMorten_esri — Tue, 20 Jul 2010 16:51:00 GMT

Replace the combobox with a textbox, add a "search" button and when clicked use the text in the textbox as the input, instead of the selected item in the combobox

Re: Find & query

PaulLeedham — Tue, 20 Jul 2010 16:53:04 GMT

Instead of using the dropdown list value as your query text use the text from a textbox then use a button click event to begin your search. Here is an example, using the syntax from the Attribute Query sample:

Dim query As New ESRI.ArcGIS.Client.Tasks.Query()
query.OutFields.Add("*")
query.Text = QueryComboBox.SelectedItem.ToString() (Change this to: TextBox.Text)

queryTask.ExecuteAsync(query)

You may also want to apply auto suggest to your text box to help users refine their searches.

Thanks,

Paul Leedham
City of Hudson
http://gis.hudson.oh.us/

Re: Find & query

TonyAlmeida — Tue, 20 Jul 2010 18:52:57 GMT

pleedham thanks for the replay, i am still unable to correctly make this work... Here is my current xaml code.
<UserControl x:Class="SilverlightApplication1.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:esri="http://schemas.esri.com/arcgis/client/2009"
    xmlns:slData="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Data">
    <Grid x:Name="LayoutRoot" Background="White">

        <Grid.Resources>
            <esri:SimpleFillSymbol x:Key="DefaultFillSymbol" Fill="#500000FF" BorderBrush="Blue" BorderThickness="1" />
        </Grid.Resources>

        <esri:Map x:Name="MyMap" Extent="-130,10,-70,60" >
            <esri:ArcGISTiledMapServiceLayer ID="StreetMapLayer"
                      Url="http://server.arcgisonline.com/ArcGIS/rest/services/ESRI_StreetMap_World_2D/MapServer"/>
            <esri:GraphicsLayer ID="MyGraphicsLayer" />
        </esri:Map>

        <Border x:Name="QueryBorder" Background="#77919191" BorderThickness="1" CornerRadius="5"
                HorizontalAlignment="Right" BorderBrush="Gray" VerticalAlignment="Top"
                Margin="5">

            <Grid x:Name="QueryGrid" HorizontalAlignment="Right" VerticalAlignment="Top" >
                <Grid.RowDefinitions>
                    <RowDefinition Height="30" />
                    <RowDefinition Height="30" />
                    <RowDefinition Height="*" />
                </Grid.RowDefinitions>
                        <TextBlock Text="US State Name contains:" Margin="10,0,0,0" VerticalAlignment="Center"/>
                        <TextBox x:Name="TextBox" Text="New" Height="23" HorizontalAlignment="Left" VerticalAlignment="Center" Width="125" TextWrapping="NoWrap"
                     Margin="10,0,10,0" FontSize="12" Background="White" AcceptsReturn="False" />
                        <Button Content="Do Query" Width="75" VerticalAlignment="Center" HorizontalAlignment="Right" Click="QueryButton_Click" Margin="0,0,10,0" Cursor="Hand" />


                    <slData:DataGrid x:Name="QueryDetailsDataGrid" AutoGenerateColumns="False" HeadersVisibility="None"
                              Background="White">
                        <slData:DataGrid.Columns>
                            <slData:DataGridTextColumn Binding="{Binding Path=Key}" FontWeight="Bold"/>
                            <slData:DataGridTextColumn Binding="{Binding Path=Value}"/>
                        </slData:DataGrid.Columns>
                    </slData:DataGrid>
            </Grid>
        </Border>

    </Grid>
</UserControl>

Re: Find & query

PaulLeedham — Tue, 20 Jul 2010 19:02:45 GMT

Can you provide a copy of your "QueryButton_Click" code from the code-behind page? This is where you create your query task so I assume this is where your problems a coming from.
Thanks,

Paul Leedham

Re: Find & query

TonyAlmeida — Wed, 21 Jul 2010 14:35:41 GMT

I tried a different example and it seems to work ok except for the DataGridColumn displaying over the text box. Also when i try to search by State i get the following error "Query Failed.ESRI.ArcGIS.Client.Tasks.ServiceException??? Here is my current xaml.

<UserControl x:Class="SilverlightApplicationFindQuery.MainPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:esri="clr-namespace:ESRI.ArcGIS.Client;assembly=ESRI.ArcGIS.Client"
    xmlns:esriConverters="clr-namespace:ESRI.ArcGIS.Client.ValueConverters;assembly=ESRI.ArcGIS.Client"
xmlns:esriSymbols="clr-namespace:ESRI.ArcGIS.Client.Symbols;assembly=ESRI.ArcGIS.Client"
             xmlns:slData="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Data">


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

        

        <Grid.Resources>
            <esriConverters:DictionaryConverter x:Name="MyDictionaryConverter" />
            <esriSymbols:SimpleFillSymbol x:Name="ResultsFillSymbol" Fill="#500000FF" BorderBrush="Blue"
BorderThickness="1" />

        </Grid.Resources>

        
        <esri:Map x:Name="MyMap" Extent="-80.05,36.93,-68.79,43.18" >
            <esri:Map.Layers>
                <esri:ArcGISTiledMapServiceLayer ID="StreetMapLayer"
     Url="http://server.arcgisonline.com/ArcGIS/rest/services/ESRI_StreetMap_World_2D/MapServer"/>
                <esri:GraphicsLayer ID="MyGraphicsLayer">
                    <esri:GraphicsLayer.MapTip>
                        <Grid Background="LightYellow">
                            <StackPanel>
                                <TextBlock Text="{Binding Converter={StaticResource MyDictionaryConverter},
       ConverterParameter=STATE_NAME, Mode=OneWay}" FontWeight="Bold" />
                                <StackPanel Orientation="Horizontal">
                                    <TextBlock Text="Population Density (2007): " />
                                    <TextBlock Text="{Binding Converter={StaticResource MyDictionaryConverter},
        ConverterParameter=POP07_SQMI, Mode=OneWay}" />
                                </StackPanel>
                            </StackPanel>
                            <Border BorderBrush="Black" BorderThickness="1" />
                        </Grid>
                    </esri:GraphicsLayer.MapTip>
                </esri:GraphicsLayer>
            </esri:Map.Layers>
        </esri:Map>




        <Canvas HorizontalAlignment="Right" VerticalAlignment="Top" Margin="0,15,7,0" Width="250" >
            <Rectangle Fill="#CC5C90B2" Stroke="Gray" RadiusX="10" RadiusY="10" Width="230" Height="55" />
            <TextBlock Text="Type a query and click Execute" Foreground="White" FontSize="10" Margin="10,5,0,0" />
            <TextBox x:Name="QueryTextBox" Width="150" Margin="15,22,0,0" Text="POP07_SQMI > 500" />
            <Button x:Name="QueryButton" Content="Execute" Margin="168,23,0,0" Click="QueryButton_Click" />
            <slData:DataGrid x:Name="QueryDetailsDataGrid" AutoGenerateColumns="False" HeadersVisibility="None"
                              Background="White">
                <slData:DataGrid.Columns>
                    <slData:DataGridTextColumn Binding="{Binding Path=Key}" FontWeight="Bold"/>
                    <slData:DataGridTextColumn Binding="{Binding Path=Value}"/>
                </slData:DataGrid.Columns>
            </slData:DataGrid>
        </Canvas>
    </Grid>
</UserControl>

Re: Find & query

TonyAlmeida — Wed, 21 Jul 2010 15:01:38 GMT

Code behind page.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using ESRI.ArcGIS.Client;
using ESRI.ArcGIS.Client.Tasks;
using ESRI.ArcGIS.Client.Symbols;
using ESRI.ArcGIS.Client.ValueConverters;

namespace SilverlightApplicationFindQuery
{
    public partial class MainPage : UserControl
    {
        public MainPage() {InitializeComponent();}

            private void QueryButton_Click(object sender, RoutedEventArgs e)
               {
            QueryTask queryTask = new QueryTask("http://sampleserver1.arcgisonline.com/ArcGIS/rest/services/" +
      "Demographics/ESRI_Census_USA/MapServer/5");
                queryTask.ExecuteCompleted += QueryTask_ExecuteCompleted;
                queryTask.Failed += QueryTask_Failed;

                Query query = new Query();
                query.ReturnGeometry = true;
                query.OutFields.AddRange(new string[] { "STATE_NAME", "POP07_SQMI" });
                query.Where = QueryTextBox.Text;

                queryTask.ExecuteAsync(query);
            }

            // Do query when execute button is clicked
            private void QueryTask_ExecuteCompleted(object sender, ESRI.ArcGIS.Client.Tasks.QueryEventArgs args)
            {
                FeatureSet featureSet = args.FeatureSet;
                GraphicsLayer graphicsLayer = MyMap.Layers["MyGraphicsLayer"] as GraphicsLayer;
                graphicsLayer.ClearGraphics();

                if (args.FeatureSet.Features.Count > 0)
                {
                    // Show selected feature attributes in DataGrid
                    Graphic selectedFeature = featureSet.Features[0];
                    QueryDetailsDataGrid.ItemsSource = selectedFeature.Attributes;

                    // Hightlight selected feature
                selectedFeature.Symbol = LayoutRoot.Resources["DefaultFillSymbol"] as ESRI.ArcGIS.Client.Symbols.Symbol;
                graphicsLayer.Graphics.Add(selectedFeature);

                // Zoom to selected feature (define expand percentage)
                ESRI.ArcGIS.Client.Geometry.Envelope selectedFeatureExtent = selectedFeature.Geometry.Extent;

                double expandPercentage = 30;

                double widthExpand = selectedFeatureExtent.Width * (expandPercentage / 100);
                double heightExpand = selectedFeatureExtent.Height * (expandPercentage / 100);

                ESRI.ArcGIS.Client.Geometry.Envelope displayExtent = new ESRI.ArcGIS.Client.Geometry.Envelope(
                selectedFeatureExtent.XMin - (widthExpand / 2),
                selectedFeatureExtent.YMin - (heightExpand / 2),
                selectedFeatureExtent.XMax + (widthExpand / 2),
                selectedFeatureExtent.YMax + (heightExpand / 2));

                MyMap.ZoomTo(displayExtent);
                    foreach (Graphic resultFeature in args.FeatureSet.Features)
                    {
                        resultFeature.Symbol = ResultsFillSymbol;
                        graphicsLayer.Graphics.Add(resultFeature);
                    }
                }
                else
                    QueryDetailsDataGrid.ItemsSource = null;
                {


                }
            }
                private void QueryTask_Failed(object sender, TaskFailedEventArgs args)
{
                    MessageBox.Show("Query failed: " + args.Error);
       }
   }
}

Re: Find & query

PaulLeedham — Wed, 21 Jul 2010 16:48:24 GMT

In order for your state name query to work you will need to have the query syntax something like:
query.Where = "STATE_NAME LIKE '%" +QueryTextBox.Text+ "%'"

As you can see from the example above the where statement needs to contain the field name and texbox syntax. I apologize if I did not make that clear in my last posting. I would recommend using just one field to search against unless you want to do some string interogation prior to creating the where string--you could check if the user is searching for numbers or strings and change the search field appropriately.

Your grid is being placed on-top of your search box because you have not configured your grid display margins correctly. You may want to place everything in a vertical stackpanel so that the grid is displayed below the textbox. In order to do this, you may want to add some logic to the display of the grid. For Example, only showing the grid if there are some features selected--try using a border around your grid and toggling the control to visible or not visible. There are other samples that use this method on the ESRI samples page.

Thanks,

Paul Leedham
http://gis.hudson.oh.us/

Re: Find & query

TonyAlmeida — Wed, 21 Jul 2010 21:50:47 GMT

Sweet! I got the grid displaying underneath the search box. How can i get it to show all the attributes for that layer and make it scroll down and up?

Re: Find & query

PaulLeedham — Thu, 22 Jul 2010 01:17:53 GMT

In order to display all the fields use the following syntax:
Replace query.OutFields.AddRange(new string[] { "STATE_NAME", "POP07_SQMI" });
With query.OutFields.Add("*");

Have you considered using the feature data grid? Check out the ESRI sample--this is a great way to display this type of information.

Paul Leedham
http://gis.hudson.oh.us

Re: Find & query

TonyAlmeida — Thu, 22 Jul 2010 14:35:32 GMT

pleedham thanks and i have looked at that sample. My main object is to have something simuler to Baldwin County (http://isv.kcsgis.com/baldwinisv/). Where you have your basic zoom out, zoom in, pan, zoom to full extents, zoom forward, zoom previous. Then if you click on tools/settings icon, it gives a new set of tools like find, locate address, identify, measure, buffer and select parcels. Pretty much the same tools as that silverlight application. I am new to silverlight and i am learning a whole hell of allot. The city of Hudson interactive mapper (http://gis.hudson.oh.us/HudsonGIS93/) is awesome! Was it made with silverlight or with ArcGIS Server Manager?