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How do I Dynamically Populate the Choices for a List Field?

Description

List fields can be dynamically populated when opened using the ON *editor event.

The list field can be populated dynamically in the ON *editor event for the List. The event is passed an object that represents the List field. You can retrieve the object using the args() function:

listChoices = args(1)

The object has a property, qList, that defines what choices are shown for the List. qList is an array of objects that contain the following properties:

text

The text to display in the choice list.

value

An optional value for the displayed choices. The value can be different from the text shown to the user.

For example, the code below shows how to populate a List with a selection of colors:

ON *editor_colors
    listChoices = args(1)

    colors = array()
    arrayPush(colors, obj("text","Red"))
    arrayPush(colors, obj("text","Orange"))
    arrayPush(colors, obj("text","Yellow"))
    arrayPush(colors, obj("text","Green"))
    arrayPush(colors, obj("text","Blue"))
    arrayPush(colors, obj("text","Purple"))

    listChoices.qList = colors
ENDON

The optional value property can be used to set a stored value different from the displayed value. This lets you create a list where the displayed value is a Customer's but the stored value is their customer ID. For example, the code below retrieves a list of customers from a SQLite database from the on-device assets. It then creates a list of choices where the displayed value (text) is the Contact Name and the stored value (value) is the Customer ID.

ON *editor_Customers
    ' Get an object for the field's list editor
    s = args(1)

    db = "SQLiteNorthwind.db"
    sql = "SELECT CustomerID, ContactName FROM customers"
    sqlresults = phoneGapTFExecuteSQL(db, sql)

    choices = array()
    if sqlresults.length<1
        arrayPush(choices, obj("value","No customers"))
        s.qList = choices
        return ' No query results
    endif

    FOR i=0 TO len(sqlresults)-1

        row = sqlresults[i]
        name = row.ContactName
        id = row.CustomerID

        ' Add the Contact Name to the list of choices
        arrayPush(choices, obj("text",name,"value",id))

    ENDFOR

    s.qList = choices

ENDON