The inheritance structure for MemberData traverses the following path:

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Class -> Container -> Global

The inheritance behavior is similar to (but not the same as) standard object-oriented programming inheritance. Visual FoxPro will first look for MemberData at the Class level along the parent hierarchy. If the particular MemberData attribute or tag is not found, then the Containership hierarchy is searched (from inner container to outer). Finally, if the search is not successful at the Container level, then MemberData is searched for at the Global level (the table specified in the _FOXCODE system variable). It is important to understand that searching occurs for a particular attribute or tag within the MemberData XML (not just the existence of MemberData itself). Therefore, it is possible to have MemberData that spans multiple locations. The following example illustrates this.

A form (Myform) containing a pageframe (Mypageframe) that has a button (Mycmd) which is inherited from _commandbutton in FFC\_base.vcx has a property called “Myprop” with MemberData associated with it. The MemberData Hierarchy for Myprop is as follows:

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** Class Level - Mycmd (Myclasses.vcx) <memberdata name="Myprop" display="MYProp" type="property"/> ** Class Level - _commandbutton (_base.vcx) <memberdata name="Myprop" display="MYPROP" type="property"/> ** Container Level - mypageframe (myclasses.vcx) <memberdata name="Myprop" favorites="True" display="myPRop" type="property"/> ** Container Level - myform (myclasses.vcx) <memberdata name="Myprop" favorites="False" helpfile="Myhelp.chm" type="property"/> ** Global Level - foxcode.dbf <memberdata name="Myprop" type="property" display="MYPROP" script="DO (_CODESENSE) WITH 'RunPropertyEditor','','MYPROP'"/>

Based on the priority of (Class -> Container -> Global), the current values for Myprop MemberData settings are as follows:

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display="MYProp" favorites="True" script="DO (_CODESENSE) WITH 'RunPropertyEditor','','myprop'" helpfile="myhelp.chm" (note: this is a custom user-defined attribute)

The following table describes the format in which MemberData information is stored in FOXCODE.dbf. Each MemberData entry requires a single record with a Type field set of "E."

¹ For events, only the favorites attribute is stored. The attribute is specified in the MemberData XML string in the Tip field.

The following is the MemberData XSD schema Visual FoxPro employs. Descriptions of special attributes are included in the schema.

Note:

The VFP MemberData schema shown below includes two MemberData document variants: a sequence of memberdata elements supported for use with Visual FoxPro classes, and a sequence of reportdata elements supported for use in extending the Visual FoxPro Reporting System. Visual FoxPro does not use reportdata elements directly, but the parallel document design allows you to use similar mechanisms to parse both types of extensions and store them in a common global store. Like class memberdata, reporting MemberData can be used both at design time and run time. For more information, see Report XML MemberData Extensions.

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<?xml version="1.0" encoding="utf-8"?> <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified" attributeFormDefault="unqualified"> <xs:element name="VFPData"> <xs:complexType> <xs:choice> <xs:sequence> <xs:element name="reportdata" maxOccurs="unbounded"> <xs:complexType> <xs:attributeGroup ref="Common"/> <xs:attributeGroup ref="ReportTemplate"/> <xs:anyAttribute processContents="lax"/> </xs:complexType> </xs:element> </xs:sequence> <xs:sequence> <xs:element name="memberdata" maxOccurs="unbounded"> <xs:complexType> <xs:attributeGroup ref="Common"/> <xs:attributeGroup ref="PropertySheet"/> <xs:anyAttribute processContents="lax"/> </xs:complexType> </xs:element> </xs:sequence> </xs:choice> </xs:complexType> </xs:element> <xs:annotation> <xs:documentation> You can add extension attributes as required. </xs:documentation> <xs:documentation> Use the name and ref attributes of the Common attribute group to declare that certain rows "belong" to you. Use the script attribute of the Common attribute group for design-time scripting. </xs:documentation> </xs:annotation> <xs:attributeGroup name="Common"> <xs:attribute name="name" type="xs:string" use="required"/> <xs:attribute name="type" type="xs:string"/> <xs:attribute name="script" type="xs:string"/> </xs:attributeGroup> <xs:annotation> <xs:documentation> The ReportTemplate-specific execute attribute is a script run at runtime (by Listeners) whereas the Common script attribute is potentially run by design-time tools. The declass and declasslib attributes are looked for in the header record's template information, not individual DataEnvironment related object records. The class and classlib attributes in the header record are not used, and can be leveraged for a custom helper class for report builders or listeners as desired. Class and classlib attributes in layout objects are meant for use in run-time and design-time templating. You can use these template classes to build custom rendering objects at runtime or to assign common style attributes at design-time, or both. </xs:documentation> </xs:annotation> <xs:attributeGroup name="ReportTemplate"> <xs:attribute name="class" type="xs:string"/> <xs:attribute name="classlib" type="xs:string"/> <xs:attribute name="declass" type="xs:string"/> <xs:attribute name="declasslib" type="xs:string"/> <xs:attribute name="execute" type="xs:string"/> <xs:attribute name="execwhen" type="xs:string"/> </xs:attributeGroup> <xs:attributeGroup name="PropertySheet"> <xs:attribute name="override" type="xs:boolean"/> <xs:attribute name="display" type="xs:string"/> <xs:attribute name="favorites" type="xs:boolean"/> </xs:attributeGroup> </xs:schema>

The following is an example MemberData XML string that demonstrates the use of the reserved Visual FoxPro 9.0 XML elements and attributes. The first section adds the BorderStyle property to the Favorites tab in the Properties window and displays the property name in upper-case.

The second section creates a custom property named MyProperty that is also added to the Favorites tab in the Properties window. The script named MyPropertyScript is executed when the ellipsis button for the custom property is chosen or you double-click the property.

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<?xml version="1.0" encoding="Windows-1252" standalone="yes"?> <VFPData> <memberdata name="borderstyle" type="property" favorites="True" display="BORDERSTYLE"override="False"/> <memberdata name="MyProperty" type="property" display="MyProperty" favorites="True" override="False" script="MyPropertyScript"/> </VFPData>

You can execute your own custom property editor when you choose the MemberData Editor… option from the Form menu, or when you right-click a property, event, or method and choose the Add to Favorites… option in the shortcut menu.

When you choose the MemberData Editor… option from the Form menu, four parameters are passed to the application specified in the _BUILDER System Variable. The following table describes the type of data passed to the parameters in the Builder application.

For example, choosing the MemberData Editor… option from the Form menu is identical to executing the following command:

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DO (_BUILDER) WITH oForm, "MemberData", 1

If no property is selected or the Properties window is closed, the last parameter will contain an empty string. If the Properties window is closed, the base object is passed as the first parameter. If multiple objects are selected, only the first one is passed as the first parameter.

When you choose the Add to Favorites… option in the shortcut menu, four parameters are passed to the application specified in the _BUILDER System Variable. The following table describes the type of data passed to the parameters in the Builder application.

For example, choosing the Add to Favorites… option in the shortcut menu when the Caption property is selected in the Property window is identical to executing the following command:

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DO (_BUILDER) WITH oForm, "MemberData", 11, "Caption"

Note:
The Add to Favorites… option in the shortcut menu is disabled when the Properties window is open for the Visual FoxPro _SCREEN application system variable.

The _GetMemberData script can be used by a custom property editor to add a _MEMBERDATA property to a container or controls when they are opened in the Form or Class designers. The _GetMemberData script is called for the following events:

• When the Form or Class Designer is opened.
  
  
• When a new control is added to the Form or Class Designer.
  
  
• When a control is selected in the Form or Class Designer, or a container is clicked to select it.
  
  

The following table lists the fields and field values in the Foxcode.dbf record.

The _GetMemberData script is not passed any parameters.

Note:
The _GetMemberData script can use the ASELOBJ( ) Function to obtain an object reference for the currently selected control or container.

The MenuHit script is called when a Visual FoxPro system menu is chosen. It can be used to override an existing Visual FoxPro dialog box with a custom dialog box.

The following table lists the fields and field values in the Foxcode.dbf record.

The MenuHit script is passed two parameters as character strings:

See System Menu Names for a listing of the internal Visual FoxPro system menu names.

To prevent Visual FoxPro from handling the menu, set the parameter object's ValueType property to V or L.

Note:
Since _Foxcode supports a single MenuHit script record and it is possible that you may want to handle multiple menu items with your own custom scripts, it is recommended that you create a default MenuHit handler record that can call other records. The Foxcode menu scripts Solution Sample contains a recommended generic Menuhit script that you can use.

The following is an example script for the MenuHit record that you can use for looking up other records in _Foxcode whose Type field = "M", Abbrev field is name of menu and Data field contains script to execute. This is the same script installed for both MenuHit and MenuContext scripts by the Foxcode menu scripts Solution Sample.

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LPARAMETERS toParameter LOCAL lnSelect, lcCode, llReturn, lScriptHandled, lcSaveUdfParms TRY * First try FoxCode lookup for Type="M" records lnSelect = SELECT() SELECT 0 USE (_FOXCODE) AGAIN SHARE ORDER 1 IF SEEK('M' + PADR(UPPER(toParameter.MenuItem), LEN(ABBREV))) lcCode = DATA ENDIF USE SELECT (lnSelect) IF NOT EMPTY(lcCode) llReturn = EXECSCRIPT(lcCode, toParameter) lScriptHandled=.T. ENDIF * Handle by passing to external routine as specified in Tip field IF !lScriptHandled lcProgram = ALLTRIM(toParameter.Tip) IF FILE(lcProgram) lcSaveUdfParms=SET("Udfparms") SET UDFPARMS TO REFERENCE DO (lcProgram) WITH toParameter,llReturn SET UDFPARMS TO &lcSaveUdfParms ENDIF ENDIF * Custom script successful so let's disable native behavior IF llReturn toParameter.ValueType = 'V' ENDIF CATCH ENDTRY RETURN llReturn

The MenuContext script can be used to override an existing Visual FoxPro shortcut menu with a custom shortcut menu, and is called just before a Visual FoxPro shortcut menu is displayed. A shortcut menu is displayed by right-clicking a window or object.

The following table lists the fields and field values in the Foxcode.dbf record.

The MenuContext script is passed a single parameter which is an object containing properties that can be referenced by the script including following:

To suppress the Visual FoxPro shortcut menu from appearing, set the parameter object's ValueType property to V or L. You can use the DEFINE MENU Command with the SHORTCUT option to create a custom shortcut menu.

NoteВ В В Since _Foxcode supports a single MenuContext script record and it is possible that you may want to handle multiple shortcut menus with your own custom scripts, it is recommended that you create a default MenuContext handler record that can call other records. The Foxcode menu scripts Solution Sample contains a recommended generic MenuContext script that you can use. See the MenuHit section above for this code.