Show field on grid if session.__protected__ulink = '' (or null)

[leetv]

Hi,

I'm trying to only show a column to a user if the user is not signed in i.e. if session.__protected__ulink is null/or ''

I have tried the following in the show/hide expression, but either way it still shows the column once the user signs in:

1) session.__protected__ulink = ''
2) isnull(session.__protected__ulink) = .t.
3) (session.__protected__ulink + '') = ''


Please help

Lee

[christappan]

Re: Show field on grid if session.__protected__ulink = '' (or null)

Are you doing server-side expressions? If not, you'll have to look into "publishing" the session variable to Javascript for client-side Show/Hide. If so, I *think* you could do this: convert_type(session.__protected__ulink,"C") = ""

[leetv]

Re: Show field on grid if session.__protected__ulink = '' (or null)

Hi Chris,

Thanks for replying... I'm doing client side. The standard grid doesn't have an option like the UX component for Server side.

I did try the example you posted above, convert_type(session.__protected__ulink,"C") = "" , and it still shows the column when signed in... this has me very perplexed!

[leetv]

Re: Show field on grid if session.__protected__ulink = '' (or null)

update: i tried to use (in the show/hide expression field of the client side properties of the grid) eval_valid("session.__protected__ulink") = .f. still didnt work.
Why is it that I read prior posts that this works in other settings, but not in this box?

[leetv]

Re: Show field on grid if session.__protected__ulink = '' (or null)

figured it out... (well i'm sure it is not a true way to do it but it works).
I did it by manipulating the SQL statement. ie.

SELECT *, :whatuser AS ulink FROM tbl etc...

the field that i want to show only while logged in is then shown if the arguemnt "ulink" field is = '' -- works like a charm. although i'm sure i'm about to find out that there is some flaw about to come and slap my in the face..

Regardless I'd like to know how I should have accomplished this...

[christappan]

Re: Show field on grid if session.__protected__ulink = '' (or null)

That'll work as far as I know.

Did you try looking up publishing session variables per my previous post? If I'm understanding correctly that you're trying to put this in the Client-Side Show/Hide expressions, you can't use XBasic or session variables because they are server-side. Use the show/hide expression smart button--the functions available to you there are the only ones available with the exception of writing your own javascript functions. This info as well as the info about publishing session variables is all there in the smart field links.

There's Xbasic running on the server, pure Javascript running on the browser, and then there's these expressions that allow simpler-than-javascript entries that get converted by Alpha Five into pure Javascript functions when the component is saved and published.

[leetv]

Re: Show field on grid if session.__protected__ulink = '' (or null)

Is there a reference on what are xbasic functions and which ones are not (i.e. js)?

I see under the expression builder for the show/hide properties there are some functions listed. Is this an all inclusive list? or can we use the many other functions available to a5?

I guess I simply forget that XB is not processed on the client and only html/js.

I did attempt to publish the session variable on the client, but i didn't work when i tried to reference it. Likely because I declared it incorrectly.

[christappan]

Re: Show field on grid if session.__protected__ulink = '' (or null)

That's the key--if it's client-side it has to be Javascript because any browser can process that, albeit slightly different on occasion. Only the server can process XBasic through an a5w page being loaded or some sort of Ajax callback to the server, many of which are built-in as validation checks, data submission, refreshing, etc.

When you use A5's Javascript methods, it uses placeholders like {grid.object} and {row.number}, but those are simply placeholders in Javascript strings.

I *think* the only place where there is client-side settings in A5 that doesn't use actual Javascript in the development is the client-side Show/Hide and Enable expressions. You have to read the information in that smart button dialog to see what's allowed there. The list there is all-inclusive unless you write your own Javascript function as referenced there.

[leetv]

Re: Show field on grid if session.__protected__ulink = '' (or null)

Thanks a ton for that explanation. This whole issue enticed me to take a 40 module basic JS course over the weekend. Although I feel a little more versed with JS I find i need to learn how to apply the JS with regards to A5 (i.e. where to write the function, how to call it, etc..).

[christappan]

Re: Show field on grid if session.__protected__ulink = '' (or null)

I probably need to take that course too. Took me a while to get it too. At this point, I've added a lot of basic Javascript to our application for further user-friendliness/robustness, but I understand just enough to get it working and often add Javascript that works some places but not in others. And, Google and returned-search programming forums are your friend. Use them.

[aburningflame]

Re: Show field on grid if session.__protected__ulink = '' (or null)

IMO - learn javascript SEPERATE from alpha.
A simple html page (in notepad) and <script> tags are all you need

<!doctype html>
<html>
<head>
<script>
function myJSFunction(){ 
        alert('Hi im javascript');
}
</script>
</head>
<body>
<a href="#" onclick="myJSFunction(); return false;">Test</a>
</body>
</html>

WHen youre comfortable with this: create a javascript.js page.
Move your script to that page
and link to it from the html like this
<script src="javascript.js"></script> or <script src="js/javascript.js"></script> (It is better to put your files in a folder - keep it organized)