Standalone and Valentina

[Trevor DeVore]

On Dec 22, 2004, at 3:18 AM, Jean-Claude SERRANO wrote:

> I have an application developed in revolution.
> This application works with a database Valentina.
> The Connection to the database is good by using Revolution on Mac OS X.
> But, I can’t connect to the database in the standalone version.
>
> Can somebody help me?

Oui, on peut vous aider.

When you build a standalone you need to make the database dll/bundles 
available to your standalone executable.  There are a couple of ways to 
do this.

Method 1: Use the Standalone Builder

If you are using Rev 2.5 (maybe 2.2 as well, I don't remember) then you 
configure your standalone application by selecting "Standalone 
Application Settings..." from the file menu or the Application Browser 
contextual menu.  From the "General" section select the "Database 
Support" checkbox and select "Valentina".  In theory this should place 
all the files you need for database connectivity in the folder the 
Standalone Builder puts your executable in.  I haven't tried it for 
Valentina but I know it doesn't work for MySQL in 2.5.

Method 2: Do it manually

This is my preferred method.  Once you understand how everything works 
it isn't too hard and you can place the required database files 
anywhere you would like.  I'm an organization freak so this suits me 
nicely :-)

When working with databases and Revolution you generally need two 
externals whether working on OS X or Windows.  The first is 
revdb.dll/.bundle which is the database abstraction external for 
Revolution.  When you call a handler such as revOpenDatabase you are 
using this external.  You can find these files in the 
"components/global environment/" folder in your Revolution application 
folder.

The second file is the database external itself, in your case 
VXCMD_macho/VXCMD.dll.  These files are located in "components/global 
environment/database_drivers/MacOSX/" and "components/global 
environment/database_drivers/Win32/".

To begin with you must copy these files in a location where your 
executable will easily be able to find them.  Here is what I do:

./myExecutable.exe
./data/externals/revdb.dll
./data/externals/revdb.bundle
./data/externals/VXCMD_macho
./data/externals/VXCMD.dll

Now that the files are in the proper location you need to tell your 
executable where to find the files.  This requires two steps.  First 
you need to set the externals property of the stack used to make your 
standalone so the engine knows where to find revdb.dll/.bundle.  Second 
you need to set the the database driver path using 
revSetDatabaseDriverPath.

Though there are other ways to set externals property of a stack the 
most straightforward way is to set the externals in the "startup" 
handler that is called when your executable launches.  You could put 
something like this in your stack script:

on startup
	local tExternals	= ""

	put	sys_AppPath() & "/data/externals/revdb.dll" &cr into tExternals
	put	sys_AppPath() & "/data/externals/revdb.bundle" after tExternals

	set the externals of this stack to tExternals

	pass startup
end startup

/**
  * Set the database driver path.
  */
on preOpenStack
	--> TEST: DISPLAY THE EXTERNAL PACKAGES AVAILABLE TO THE STACK
	--> SHOULD DISPLAY "RevDB".
	answer the externalPackages of this stack

	revSetDatabaseDriverPath (sys_AppPath() & "/data/externals/")

	pass preOpenStack
end preOpenStack


/**
  * Returns the path to the executable.
  */
function sys_AppPath
   local tPath	= ""

   put address into tPath
   set itemDel to ":"
   delete item 1 of tPath

   return tPath
end sys_AppPath


This code will set the externals of the stack and display a dialog box 
showing which external packages are available to the stack.  If 
everything went as planned then the dialog box should display "RevDB".  
Hopefully this will get you started.  If you aren't using revDB and are 
just accessing Valentina directly using the XCMD then you would do 
things slightly differently.  If this is the case then let me know I 
can explain how to do that.

Hope this helps,


-- 
Trevor DeVore
Blue Mango Multimedia
trevor at mangomultimedia.com