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Item Picker Form Element

The Item Picker form element displays a filterable list of items and optionally allows the user to select one or more items. If you configure an item picker to allow selection, you can access the selection later in the workflow to perform additional processing.

The items can be any type of object, for example, each item could be a map feature. In this case, you can configure an item picker to display multiple lines of Markdown-formatted information about each item, including feature attributes.

If the items have geometry, the geometries are highlighted on the map. Different highlighting is used for items that are unselected (), selected (), or hovered over (). This is shown in the screen capture below.

The screen capture shows an item picker that allows the user to select multiple items. Each item has a checkbox beside it for selecting the item. Single-selection item pickers have radio buttons instead of checkboxes, and item pickers that do not allow selection have nothing beside the items.

Example of the Item Picker form element, shown in a Geocortex HTML5 viewer

See also...

Use the Item Picker Form Element for Visualization

Item Picker Properties

The following table describes the properties of the Item Picker form element. Some properties can be configured in the Properties panel in Workflow Designer. These properties have configuration information in the table. Similarly, some properties can be accessed in expressions. These properties have information about how to access the property in an expression.

If a property can be configured in the Properties panel and accessed in expressions, the property has two names: the name that appears in the Properties panel and the name that is used in expressions. Both names are given in the table. Sometimes the names only differ in capitalization, for example, Visible (in the Properties panel) or visible (in expressions).

Properties of the Item Picker Form Element

Item Picker Events

The following table describes the events associated with the Item Picker form element. As in Workflow Designer, the events are listed in the order that they fire.

Events for the Item Picker Form Element

Configure the Items in an Item Picker

As part of the configuration of an item picker, you must specify where to get the items to present to the user. This is done using a subworkflow that runs when the item picker loads.

Workflow Designer provides templates that you use as the starting point for the subworkflow:

• ArcGIS Query: The ArcGIS Query template provides a subworkflow that queries ArcGIS Server for items to use in the item picker.

• Blank: The Blank template provides a blank subworkflow to use as the starting point for the subworkflow.

Use the Item Picker Element's ArcGIS Query Template

The ArcGIS Query template provides a subworkflow that queries ArcGIS Server for items to use in the item picker. You will need to adapt the subworkflow to work within your workflow.

Subworkflow for the ArcGIS Query template

The subworkflow has the following activities:

1. Query Layer: This activity queries an ArcGIS Server map service for features on a particular layer and filters the features. The query also gets the specified feature attributes that you want to use later in the workflow.

2. Get Form Element Items From Features: This activity converts the features returned by the query to items that can be used by the item picker. Form elements cannot use features directly—the features must be converted first.

3. Set Form Element Items: This activity associates the converted features with the item picker.

The ArcGIS Query template is based on a query for US state names. When the item picker loads, the subworkflow queries the States layer for US states. The subworkflow then converts the features and assigns them to the item picker to display in a list.

To use the ArcGIS Query template:

This procedure presents one possible adaptation of the template which you can build on in many ways. To explore additional capabilities of an activity, refer to the activity's documentation.

1. In the Items area of the item picker's properties, click ArcGIS Query.

   The subworkflow opens.

2. Query Layer: Adapt the Query Layer activity to work in your workflow:

   1. Update the Description property to describe what you are querying for.

   2. Set the Url input to the URL of the layer that you want to query.

      Click the Expand icon to open a larger input area.

   3. In the Where box, enter a SQL WHERE clause to filter the features that the query returns.

      For example, if you only want to show sparsely populated states, you could use a Where input similar to this:

      POP2007 < 1000000

      Setting the Where input to 1=1 gets all the features.

      To do a literal text search on the display field, configure the Text input instead of the Where input.

      To perform a spatial query, configure the Geometry input. You can filter on both attribute values and location by configuring the Geometry input and the Where or Text input.

   4. Change the Output Fields input to specify the fields that you want the query to return. Use commas to separate the field names.

      If you want to get all the fields, enter an asterisk (*) in the Output Fields input.

   5. Make sure Return Geometry is set to true and set Output Spatial Reference to the spatial reference of the map.

      This ensures that the geometries can be drawn in their correct locations on the map.

      If you leave Output Spatial Reference blank, the spatial reference of the map service is used.

      If the geometries do not appear on the map in the running workflow, refer to the console (F12). When the geometries cannot be drawn, the map's spatial reference and the value of Output Spatial Reference are logged to the console, provided Value Field Name is blank. This allows you to check whether the spatial references are different.

   6. Configure any other properties and inputs that you want to customize. See Query Layer Activity for information.

3. Get Form Element Items From Features: Adapt the Get Form Element Items From Features activity to work in your workflow:

   You should not need to change the Features input. The Features input specifies the features returned by the query.

   1. Configure the Label input:

      • If you want the items to consist of a single field, set the Label input to the name of the field.

        For example, to use the value of the STATE_NAME field as the items, set Label to STATE_NAME.

        or

      • If you want the items to contain formatting or multiple fields, set the Label input to the Markdown-formatted information that you want to include in each item. Surround each field name with curly brackets. To go to a new line, type a backslash (\) and press Enter.

        For example, suppose you set Label to the following:

        **{STATE_NAME}**\
        Abbreviation: {STATE_ABBR}\
        2007 Population: {POP2007}

        The items will have three lines, each of which displays a field, for example:

        • Maryland
        • Abbreviation: MD
        • 2007 Population: 5727376

        If a field placeholder such as {STATE_NAME} appears in the items at run time instead of being replaced by the field's value, the workflow could not find the field. This can be caused by a spelling or capitalization error in the placeholder or by forgetting to include the field as an output field in the Query Layer activity.

   2. Make sure the Value Field Name input is blank.

      This ensures that the item is the entire feature, including the geometry which will be drawn on the map.

   3. Configure any other properties that you want to customize. See Get Form Element Items from Features Activity for information.

4. Set Form Element Items:  You should not need to change the inputs. The Items input specifies the items created by the Get Form Element Items From Features activity. Leaving the Element input blank assigns the items to the form element that the subworkflow belongs to.

5. To return to the form designer, click Display Form in the breadcrumbs.

   If you need to re-open the subworkflow, click Edit in the Properties panel or double-click the item picker in the form preview.

Use the Item Picker Element's Blank Template

The Blank template provides a subworkflow with an Event block and nothing else in it. You will have to create the subworkflow from scratch.

Subworkflow for the Blank template

By its very nature, the Blank template can be used to create a wide variety of subworkflows that get items for an item picker. For example, you might have a feature set that contains the items you want to use.

If the feature set doesn't exist in the workflow yet, you may want to use the ArcGIS Query template.

You could use the following activities to get the items from an existing feature set:

1. Get Form Element Items From Features: This activity converts the features to items that can be used by the item picker.

   Form elements cannot use feature sets directly—the feature set must be converted first.

2. Set Form Element Items: This activity associates the converted items with the item picker.