Modify an existing form

Modifying a form involves either changing the attributes of, or adding elements to, an existing form. The element you want to modify must exist in the same hierarchy as the original element. If you are adding an additional element to an existing element, the new element must have all the attributes required of a new element.

For example, if we add two columns—ddmin and ddmax—to the analog form, and these two new columns are grouped under the RTUDD group on the Input tab of the analog Row Details dialog box, the analog.Alter.xml file must declare the following:

• The ddmin and ddmax columns represent a modification to the Input tab of the analog Row Details dialog box.

• A group called RTUDD is being added.

• The ddmin and ddmax columns are being added to the RTUDD group.

The ComesAfter attribute is used for the SubGroup to ensure that the new RTUDD group is placed in the correct order.

Important: If a column defined in the <table>.Alter.xml file depends on a column that does not exist in either the <table>.xml file or the <table>.Replace.xml file, the column will not appear on the form.

For example, the Priority Display column is removed from the analog form in the analog.Replace.xml file, but exists in the analog.xml file. The Station Framework component has added an analog.Alter.xml file, and now adds a column called Display Order. This newly added column has a ComesAfter attribute stating that it comes after the Priority Display column. Since the Priority Display column is not defined in the analog.Replace.xml file, the Display Order column will not display because it depends on a non-existent column. If the IsVisible attribute for the Priority Display column is set to false in the analog.Replace.xml file, the Display Order column defined in the analog.Alter.xml file will appear on the form because the Priority Display column exists, but is hidden.

<?xml version="1.0" encoding="UTF-8"?>

<DataSetTables xmlns="http://www.telvent.com/DataSetSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.telvent.com/DataSetSchema ..\..\DBEditSchemaAlter.xsd">

<DataSetTable

Name="analog">

<Group

Name="Input">

<SubGroup

Name="RTUDD"

ComesAfter="Trend Indicator Image"

Label="RTUDD"

IsArray="false"

ToolTipText="RTUDD">

<Field

Name="rtudd_@ddmin"

RowLabel="RTUDD Minimum"

ColumnLabel="RTUDD Minimum"

ToolTipText="RTUDD Minimum"

TabOrder="500"

IsRequired="false"

IsReadOnly="false"

IsVisible="true"

DisplayWidthToUse="Minimum">

</Field>

<Field

Name="rtudd_@ddmax"

RowLabel="RTUDD Maximum"

ColumnLabel="RTUDD Maximum"

ToolTipText="RTUDD Maximum"

TabOrder="550"

IsRequired="false"

IsReadOnly="false"

IsVisible="true"

DisplayWidthToUse="Minimum">

</Field>

</SubGroup>

</Group>

</DataSetTable>

</DataSetTables>