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Juan Carlos Pontaza at Fidelity has created something that a lot of people have been asking about on the forums recently, and that is the Dynamic Listbox. There are a lot of people who wish to have something similar to the Master/Detail Combo example for two listboxes on the same row. This was finally achieved by the Dynamic Listbox, which was included in a modified version of Grid 3.41.

Basically, a standard listbox consists of keys and values. Below is the sample for a Listbox defined with an XML island:


<ntb:textcolumn label="Lookup" xdatafld="ProductCategoryID" width="150">
<ntb:listboxeditor
datasourceid="lookupCategoryDataSource"
displayfields="ProductCategoryName"
valuefield="ProductCategoryName" >
</ntb:listboxeditor>
</ntb:textcolumn>

<!- then, outside the <ntb:columns> tag… ->

<ntb:datasources>
<ntb:datasource id=”lookupCategoryDataSource”>
<ntb:datasourcestructure
id=”lookupCategoryDataSource”
Keys=”ProductCategoryID”
FieldNames=”ProductCategoryID|ProductCategoryName”>
</ntb:datasourcestructure>
<ntb:data id=”lookupCategoryDataSource”>
<ntb:e a=”1″ b=”Cleaners” xi=”0″></ntb:e>
<ntb:e a=”2″ b=”Solvents” xi=”1″></ntb:e>
<ntb:e a=”3″ b=”Adhesives” xi=”2″></ntb:e>
<ntb:e a=”4″ b=”Fuels” xi=”3″></ntb:e>
<ntb:e a=”5″ b=”Waxes” xi=”4″></ntb:e>
<ntb:e a=”6″ b=”Dyes” xi=”5″></ntb:e>
<ntb:e a=”7″ b=”Paints” xi=”6″></ntb:e>
<ntb:e a=”8″ b=”Sealants” xi=”7″></ntb:e>
</ntb:data>
</ntb:datasource>
</ntb:datasources>

In this example, The column is being bound to a ProductCategoryID field and you are getting the ProductCategoryName from the datasource value that matches the ProductCategoryID to be able to render the correct text.

In his case with the dynamic loader, we do not need to display the value, because the datasource will be different per row, so at renderer time we need the description value to write it on the cell. To solve this, the developer has to provide that other column too. For example: