Application Development

As of Panther 5, you can import and export data from a Panther screen in XML format.

Defining XML Properties

To use the XML feature available as of Panther 5, the screen and its widgets must have the appropriate XML properties set. There are four XML properties that can be specified for widgets or screens:

XML Tag

A tag associated with the screen, container, or widget.

XML Attributes

Additional information to be output in the opening tag following the XML Tag value.

For example, if the XML Tag is gadget and the XML Attributes is magnetic color='blue', the opening tag in the generated XML would be:

<gadget magnetic color='blue'>

Note: If you use special characters, such as > or <, they must be escaped.

XML Prefix

Data to be output before the opening tag. This property can contain more than one line of text and will be output even if the widget does not have the XML Tag property set.

XML Postfix

Data to be output after the closing tag. This property can contain more than one line of text and will be output even if the widget does not have the XML Tag property set.

The screen being used for XML generation must either have the XML Tag property specified or both the XML Prefix and the XML Postfix properties specified.

For screens, if the XML Prefix property is empty, the generated XML starts with the following line:

<?xml version='1.0'?>

If a different opening line is needed, specify it in the screen's XML Prefix property.

Processing XML Properties

For screens and other containers (boxes, tab decks, tab cards and grids), Panther generates the following:

• If specified, the XML Prefix property value is output.

• The opening tag and any attributes are output.

• XML is generated for the widgets within the container.

• The closing tag is output.

• If specified, the XML Postfix property value is output.

  Note: Even if the container does not have any XML properties specified, widgets in it will be included in the generated XML when they have XML properties set.

For data entry and selection widgets (dynamic labels, single line text widgets, multiline text widgets, option menus, combo boxes and list boxes), Panther generates the following :

• If specified, the XML Prefix property value is output.

• The opening tag and any attributes are output.

• The data from the widget is output.

• The closing tag is output.

• If specified, the XML Postfix property value is output.

Processing XML for Multiple Occurrences

When a grid is converted to XML, the maximum number of occurrences of each grid member having an XML Tag property determines the number of occurrences to output. All offscreen data will be written to the XML.

Processing Hidden Widgets

It is recommended that all widgets used in the XML generation have the same value for Hidden Always. Either all of the widgets must be set to Hidden Always, or none of the widgets must be set to Hidden Always.

Generating XML

You can generate XML by calling one of the following functions:

• sm_xml_export and its variants generate the XML to a buffer. Since the buffer can contain TAB and NL characters, sm_ww_write should be called put the output in a word wrapped array when calling these functions from JPL.

• sm_xml_export_file and its variants write the generated XML to a file.

The form of the function depends on how you specify the screen or LDB.

• To generate XML for the current screen, call sm_xml_export or sm_xml_export_file.

• To specify the screen by GSD, call sm_n_xml_export or sm_n_xml_export_file.

• To specify the screen by Object ID, call sm_obj_xml_export or sm_obj_xml_export_file.

The following JPL procedure generates XML for the current screen to the file titles.xml:

proc export
	call sm_xml_export_file("titles.xml")
	return

---

Importing XML

You can import XML by calling one of the following functions:

• sm_xml_import and its variants import XML from a buffer. Since the buffer can contain TAB and NL characters, sm_ww_read.can be used to provide this buffer when calling these functions from JPL.

• sm_xml_import_file and its variants import XML from a file.

The form of the function depends on how you specify the screen or LDB.

• To import XML into the current screen, call sm_xml_import or sm_xml_import_file.

• To specify the screen by GSD, call sm_n_xml_import or sm_n_xml_import_file.

• To specify the screen by Object ID, call sm_obj_xml_import or sm_obj_xml_import_file.

The following JPL procedure reads in XML for the current screen from the file titles.xml:

proc import
	call sm_xml_import_file("titles.xml")
	return

Notes:

• In order to write data values into fields, the names of the fields and their corresponding containers must match the names specified in the XML file.

• Data originally exported from a multi-line text widget must be imported back into a multi-line text widget.

Sample XML File

The following file contains the data from one of the videobiz database screens:

<?xml version='1.0'?>
<titles>
<title_id>2</title_id>
<name>Aliens</name>
<genre>SCFI</genre>
<rating>R</rating>
<release_year>1986</release_year>
<title_id>4</title_id>
<name>All the President&apos;s Men</name>
<genre>DRAM</genre>
<rating>PG</rating>
<release_year>1976</release_year>
<title_id>26</title_id>
<name>Moonstruck</name>
<genre>COM</genre>
<rating>PG</rating>
<release_year>1987</release_year>
</titles>