Executing the MouseHelp method causes the cursor to change to an arrow/question mark combination. The user can then click any of the controls on the form and if Popup Help is assigned it will appear.
If there is no Popup Help assigned, a "forbidden" symbol (circle and slash) will be superimposed on the cursor. This symbol is a significant advantage over other help methods, since it graphically shows that a help topic does not exist where clicking would be futile.
In certain circumstances the user can also click on another form and still get Popup Help. This has been enabled to allow easy support for MDI children.
Note that Popup Help is available wherever a standard Borland "Hint" would be available in the same circumstances. Hints are sometimes not available on disabled controls - which was apparently a design decision we don't actually understand - you often want to know why a control is disabled! For that reason, the TMFMHelp component allows you to put a Popup Help feature on disabled buttons, and most other features that Hints are excluded from.
Example:
The following code is all that is required to initiate mouse activated Popup Help. It assumes the TMFMHelp control is named MFMHelp1 and that it is in response to a click on a SpeedButton:
procedure TForm1.SpeedButtonClick(Sender: TObject);
begin
MFMHelp1.MouseHelp;
end;