DataWindow.HelpRequest Method |  |
Provide a method that is invoked when the user requests help from the application using one of the available context-sensitive help mechanisms.
Namespace:
VO
Assembly:
VOGUIClasses (in VOGUIClasses.dll) Version: 2.19
Syntax VIRTUAL METHOD HelpRequest(
oHelpRequestEvent
) AS USUAL CLIPPER
[ClipperCallingConventionAttribute(new string[] { ... })]
public override Usual HelpRequest(
Usual oHelpRequestEvent = default
)Parameters
- oHelpRequestEvent (Optional)
- Type: Usual
The HelpRequestEvent object that describes which item help is being requested for.
Return Value
Type:
UsualRemarks  Tip |
|---|
|
Important! This is a callback method used by X#.
Normally, it should not be called in your application code.
|
This event handler is invoked only if the help mechanism has been enabled for the current data window (or one of its owners). The help mechanism is enabled by assigning a HelpDisplay object to the windows HelpDisplay property.
The default implementation of this event handler is to display the help topic that is associated with the control, menu command, or window region with focus when the HelpRequestEvent was generated. This is accomplished using HelpDisplay:Show(
cKeyword), where
cKeyword is either a HyperLabel:HelpContext property or a default keyword generated by this event handler in cases where a hyperlabel is not available.
If there is no hyperlabel for an item, the keyword generated is as follows:
A HELPCONTROL request generates the keyword Control_xxxx, where xxxx is the numeric ID of the control, in decimal. For example, an OK push button might generate the keyword Control_101.
A HELPMENU request generates the keyword Menu_xxxx, where xxxx is the "cleaned" text of the menu command. The cleaned text has all leading and trailing spaces and the ampersand character (&) removed. In addition, all sequences of spaces are replaced by a single underscore, and the string is truncated at the first tab character.
For example, the keyword generated for the menu command:
Save &As\tF3
is
Menu_Save_As
A HELPWINDOW request generates one of the keywords listed in the table below, depending on the window region that has focus.
Keyword Window Region
Window_Border Border
Window_Caption Title bar
Window_MaxBox Maximize button
Window_MinBox Minimize button
Window_SysMenuBox System menu button
Window_Unknown Any area of the window not explicitly identified in this table
Window_WindowCanvas Canvas area
| Tip |
|---|
| If the Window_Unknown keyword is generated, the default behavior of HelpRequest() is to display the Contents topic as defined in the HelpDisplay (that is, HelpDisplay:Show("HelpIndex")). |
If a HELPWINDOW request is received, while DataWindow:HelpContext is defined, DataWindow:HelpRequest() uses the HelpContext property, regardless of the window region that has focus.
Refer to the "GUI Classes" chapter in the Programmer's Guide for more information on programming an online help system for your application.
See Also 
