Mark, At 07:32 PM 21/09/2012, Mark Rotteveel wrote: >On Fri, 21 Sep 2012 08:21:54 +0100, Andrea Raimondi ><andrea.raimo...@gmail.com> wrote: >> Oh I can answer that :-) A component in Delphi terms is a self contained >> class that can be placed on a form and that is not necessarily visible >at >> run time :-) Visible components, in Delphi, are called controls :-) > >Thanks, so my guess was right that it is a UI element, but then >not-visible ;)
Ah, no, not quite. Confusion comes here from some slight linguistic mismatches. ;-) A component is a class. Components are usually grouped in higher-level classes by inheritance, although that's far from the whole story in ObjectPascal. The non-visual components - such as a TIB_Events in IBOBjects - carry methods (functions and procedures) and properties that wrap the API calls and all their bits and pieces. The visual components are the things you place on forms (screens), such as grids, edit boxes and all the other things. They are known as controls. Special classes of controls are containers for data from databases. They are known (astonishingly!) as data-aware controls. These are linked to the non-visual database components by a linker component called a datasource, to provide the UI for working with data. Is this clearer, or not? ;-) ./hb
