Guys, Guys, VCL are Visual Components Libraries, and they are exactly what their name says: for you they appears visually in the IDE on component palettes, from where you may pick-up and place on your forms. For the system - more specifically, for the Delphi IDE and Delphi Compiler - VCL are a Borland protocol embedded in Delphi - actually what makes Delphi - which allows packing code in libraries and integrating from the Delphi's IDE palette to your forms and your code. There are two ways to see VCLs' visibility: at design-time and at run-time. During design-time all VCLs are visible, from where the letter V in VCL comes. At run-time, only some VCLs are visible on your forms, from where the confusion visual/non-visual VCLs. So, VCL is a way to pack code and to display it on palettes. The packed code can do anything; some VCLs just wraps around other useful code from Windows: on the Win32 tab of the palette you will find Windows controls exposed as VCL, sometimes enhanced; on the System palette - you will find some system code interfaces as the Timer. Another VCL classification is data-aware and non-data- aware, and this relate to the ability of the component to bind to some data- sources. Data-aware VCLs comes usually related with a database model, providing connectivity to that database type. Some data-aware collections are more general than other, giving universality, but reducing all supported models to their common denominator. Other collection gives connectivity to other channels as TCP/IP, Internet etc; or other facilitate the interfacing with other programs as Office Automation. With just a little bit of study, you may find programming in VCLs very convenient - it helps you to keep your code as encapsulated as possible and easy to use it across many of your programs; eventually - if generalized enough - you may even sell it. Unwisely used it will over-crowded your palette, as can do buying or downloading from too many sources. Note that since some recent versions of Delphi, there is another protocol of packing code - CLI (or something like that) - which is closer to Microsoft's as in .Net or other technologies as Linux. VCL and CLI cannot choexist in the same application, which should define two type of Delphi applications, but allpications are just EXEs files, aren't they?
Horia -------------------------------------------------------------------------------- From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of Nesler, Thomas J Sent: Tuesday, January 03, 2006 11:25 AM To: [email protected] Subject: RE: [delphi-en] vcl? Hi Pete! I have always believed that the VCL contains standard Win32 components which have been improved by Borland to make life easier for programmers. Therefore, the inputbox (which is a visual compnenent) is not part of the VCL because it is only a wrapper around a standard Win32 component. The Editbox, on the otherhand, is part of the VCL because it takes a standard Win32 component and improves it (passwordChar). If you look at the help for Tedit and select properties, you can see those properties which come from TCustomEdit as opposed to the properties from TWinControl, or Tcontrol. Hope this clarifies things. Tom Nesler Live long!... Code Well!... and Prosper!... V -----Original Message----- From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of Software Developer Sent: Monday, January 02, 2006 4:07 PM To: [email protected] Subject: Re: [delphi-en] vcl? Visual Component Library --- petesouthwest <[EMAIL PROTECTED]> wrote: > Hi > > Sorry to ask what is probably a daft question, but > can someone please > explain exactly what the vcl is? > > Is it only the graphical components of delphi? > > Is for example an input box created by a line of > code (ie > inputbox('','','') part of the vcl or somethign > different? > > Thanks for any help given > Pete > > > > ----------------------------------------------------- Home page: http://groups.yahoo.com/group/delphi-en/ To unsubscribe: [EMAIL PROTECTED] Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/delphi-en/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
