Ask before closing Alpha 5 v6

[Paul Main]

I have looked for an answer to this but can't find a solution. I am sure there is one. My app works fine and I have locked it down so the user can't use the red X buttons to escape forms. But now I have gone full screen which looks tidier and more professitional I find the Alpha Five red X button works to well in that it closes the app and Alpha Five with no warning. This basically screws things up for me.

Is there a way of testing the Alpha Five red X before shut down and where will I find how to do it?

Thanks

Paul

[Jim Chapman]

Hello Paul,

Check out the can_database_exit() function. You would run your script in possibly an autoexec script which registers the code. Then when a user tries to close the database, your code would run and have the opportunity to cancel() the exit.

Jim

[Paul Main]

Ask before closing Alpha 5 v6

Hello Paul,

Check out the can_database_exit() function. You would run your script in possibly an autoexec script which registers the code. Then when a user tries to close the database, your code would run and have the opportunity to cancel() the exit.

Jim

Jim, thanks for this it seems to be what I need. I would appreciate an example as I am still very much a beginer and find worked example easier to relate back to the reference manual.

Thanks

Paul

[Jim Chapman]

Ok,

Don't know if you have an autoexec script or not. If not just create one, and add something like the following code. If you already have one, just add to the existing code.

'This is the code you want to run when someone tries to close the database or A5:

vCode =<<%a%
vReturn = ui_msg_box("ARE YOU SURE?","Do you really want to exit?",UI_YES_NO)
if vReturn = UI_NO_SELECTED
	cancel()
end if 
%a%

can_database_exit(vCode)

In an autoexec script, this code runs at the startup of the database and registers (defines) that the code contained in the vCode variable will be run when an attempt to shutdown the database occurs.

So when an attempt to shut down the database occurs, the code is run. This example code only pops up a message box asking the user if they are sure they want to exit (the database or, because the database has to close if you are shutting down A5, A5). If they select the 'No' button, then the IF statement runs and issues a cancel() command which aborts the shutdown.

Now you probably want to prevent the user from shutting down except when they use your predefined approach to shutting down. So I'll assume that you want to only allow a shutdown when the user presses a particular button on a particular form. So change the autoexec script that registers the code to run when a shutdown is attempted to:

vCode =<<%code%
dim Global vA5ShutDownVariable as l
if vA5ShutDownVariable = .f.
    cancel()
end if 
%code%

can_database_exit(vCode)

Now assuming that you have a particular button which is the only place you want to allow your users to shut down from. On this button's OnPush event, place the following code:

dim global vA5ShutDownVariable as l
vA5ShutDownVariable = .t.
a5.Close()

Now whenever a user tries to shut down, the registered can_database_exit() code runs. It dimensions (declares) a global variable named "vA5ShutDownVariable. This variable is dim'med (dimensioned) as a logical variable. But as this code only creates it, and doesn't assign a value, it will be by default a logical false value (.f.). Now the can_database_exist() code checks to see if this variable is True. It is not True so the action is cancelled and the database is NOT closed.

But if you press your button, the button code also dim's this variable AND sets its value to TRUE (.t.), then it attempts to close A5. This causes the can_database_close() code to run which now will see that the vA5shutDownVariable is now true, and allow A5 to close.

One point that you may find confusing is that we are defining the variable in both places. This does not overwrite the variable if it already exists. You might say why do this, why not just check the value of the vA5ShutDownVariable in the can_database_close() code. The reason is, if a shut down is attempted from any other place in the application other than your Close Button, this variable does not exist. So checking the value of a variable that does not exist will raise an error. This is why I dim'med the variable in both code locations.

Another 'gotcha' to remember while testing is that the can_database_close() code is 'additive'. IOW, if you run a script that assigns code to the can_database_close event, it ADDS TO any existing code in this instance of the database. So if you make an error in your code, just correcting the error and re-running the script will not clear out your first defective code, it adds to it. This is a good thing, but it may cause you to do a 'three fingered salute to get A5 closed down :-)

Good luck,
Jim

[Paul Main]

Ask before closing Alpha 5 v6

Jim,

Now this explanation I understand. Can't thank you enough. I appreciate the time you have taken to put this down.

I am sure this will help a great many who are new to Alpha 5.

Best Regards

Paul