Great minds think alike.... LOL
The DLL(s) can contain the GUI(s) I have completed two different projects along this line. In one, each DLL contains a feature. When the feature is selected, the DLL places its base panel on the EXEs form. The user then interacts with the DLL. This project belongs to a client so I don't have the code. The other one is an extensible simulator. Each component is a separate DLL and an implementation of the same abstract class. In this case, each DLL has it's own form. Each DLL exports a function that returns a class (class of) type. This a class type can be used to call the class constructor. The EXE creates a list of DLLs by looking in a directory. It builds an array of classes by loading each DLL and calling it's API to return the class. There are Class methods that return data about the class including a descriptive string to display for user selection. I own this code, so I can show it if there is interest. Doug Charlie Chambers wrote: > Hi Neal, > What you need to remember is that the main unit code is to cover the needs of > the GUI of the main form and the DLL will take care of areas you wish to > update for the future. I'd put the update code in the main form code unit > and load the DLL as part of the activation of the main unit. When you wish > to download a new update, i'd unload DLL, download then reload the new DLL. > Having said this, this is precisely where the term "DLL Hell" came from. It > might be good to have code to revert to a previous dll just in case to cover > all bases or at least, put a DLL version function into the DLL. > > Looks like Doug beat me to this! <g> > > Cheers, > Charlie > > > > > ----- Original Message ----- > From: Neal Campbell > To: [email protected] > Sent: Thursday, January 15, 2009 1:14 PM > Subject: Re: [delphi-en] Problem with ShellExecute > > > Hi Charlie > > Please excuse my newness to the list and Delphi programming (I am > returning after 10+ years). In the DLL example, how would that work? > The main program will call the functions in the DLL to determine if a > new release is available and downloads it, while quitting the main > program? How does the DLL stay alive when you kill the main program so > that you can delete/init it with the new version? > > I need to do this myself and am learning from this email chain tremendously? > > Why hasn't someone created a small framework for this like we have for > OS X (Sparkle)? > > Thanks > Neal Campbell > Abroham Neal Software > > On Thu, Jan 15, 2009 at 12:33 PM, Charlie Chambers > <[email protected]> wrote: > > Hi Bobby, > > Another idea is to put the update functions/procedures into a DLL > > and just update the DLL as opposed to the full exe. > > > > Cheers, > > Charlie > > > > ----- Original Message ----- > > From: Bobby Clarke > > To: [email protected] > > Sent: Thursday, January 15, 2009 8:09 AM > > Subject: [delphi-en] Problem with ShellExecute > > > > I wanted to provide a web update facility for my program B.exe and > > decided that the easiest way was to write a small control program, > > A.exe, which checked the web for updates to program B.exe and then > > starts, via ShellExecute, the latest version of B, perhaps B009.exe. > > > > This all works very well. The problem comes when I try to update the > > control program A.exe. Clearly the new version must be called A.exe so > > that all the shortcuts work. I can download A.new and the only task now > > is to delete A.exe and rename A.new to A.exe. I have written a small > > console program C.exe that does this. The problem is knowing how to > > start C.exe. If I start with a ShellExecute from A.exe, the file A.exe > > seems to be locked even after A has finished and even if C.exe waits for > > two minutes before trying to change the A filenames. The A filenames > > themselves are not locked as I can change using Windows Explorer during > > the 2 minute wait. I can even change the names by hand-starting a > > different occurrence of C.exe. Starting C from B fails as the A file is > > still locked. > > > > I could place C.exe to be run on the next re-boot, but this seems messy > > and interferes with the user's control of his PC. Is there another > > option? All suggestions welcome. How do others update programs using the > > web? > > > > Bobby Clarke > > > > [Non-text portions of this message have been removed] > > > > [Non-text portions of this message have been removed] > > > > > > > > > [Non-text portions of this message have been removed] > > > ------------------------------------ > > ----------------------------------------------------- > Home page: http://groups.yahoo.com/group/delphi-en/ > To unsubscribe: [email protected]! Groups Links > > > > > ------------------------------------------------------------------------ > > > No virus found in this incoming message. > Checked by AVG - http://www.avg.com > Version: 8.0.176 / Virus Database: 270.10.7/1895 - Release Date: 1/15/2009 > 7:46 AM > > ---------- ---------- No virus found in this outgoing message. Checked by AVG - http://www.avg.com Version: 8.0.176 / Virus Database: 270.10.7/1895 - Release Date: 1/15/2009 7:46 AM [Non-text portions of this message have been removed]
