Enabling Editable Fields in a Canvas Grid

[Jeff_Stone]

Our VFP apps allow clients to tag deals listed in a grid to enable batch processing of those deals. Using the below page load() proc, the grid successfully populates but the grid is not modifiable even though the "editable" box is checked. This makes sense as the "SELECT" results are not attached to a table or cursor. (In VFP, we just allow the Chosen column to be modified as a checkbox -- haven't figured how to get the checkbox in Lianja yet.)

proc page1_load()
messagebox("Made it 1")
m_deals = lianja.getelementbyID("gDealList") //get the Grid ID
m_deals.addItems("select chosen,long_name,filename,settle_dt from deallist597") //populate the Grid
endproc


So, I wanted to try populating the grid from a readwrite cursor to see if the would solve the problem using the following code:

proc page1_load()
messagebox("Made it 1")
select chosen,long_name,filename,settle_dt from deallist597 into cursor deals597 readwrite
m_deals = lianja.getelementbyID("gDealList")
m_deals.addItems("select * from deals597")
endproc

However, this code produces the following error messages:

Thu May 9 16:27:19 2013
**** Lianja error ****
DECLARE _DAO000C READ ONLY CURSOR FOR select * from deals597;

^
METHOD 'ADDITEMS' not found
Called from procedure - page1_load at line 13

Naturally the grid display is now empty. Any suggestions?

[Jeff_Stone]

fwiw, if I remove the READONLY clause, the debug errors window still shows:

Thu May 9 16:52:47 2013
**** Lianja error ****
DECLARE _DAO0012 READ ONLY CURSOR FOR select * from deals597;
^
METHOD 'ADDITEMS' not found
Called from procedure - page1_load at line 13

Also, the SQl command:
select chosen,long_name,filename,settle_dt from deallist597 into cursor deals597 readwrite

works fine in VFP 9

[HankFay]

fwiw, if I remove the READONLY clause, the debug errors window still shows:

Thu May 9 16:52:47 2013
**** Lianja error ****
DECLARE _DAO0012 READ ONLY CURSOR FOR select * from deals597;
^
METHOD 'ADDITEMS' not found
Called from procedure - page1_load at line 13

Also, the SQl command:
select chosen,long_name,filename,settle_dt from deallist597 into cursor deals597 readwrite

works fine in VFP 9

Hi Jeff,

every cursor in Lianja is readwrite; try leaving that off.

Also, you can use that SELECT to populate the grid directly.

For more control, you can create a virtual table, which allows you to set various properties, etc., and also to change backends as you wish, using a macro "{m.cMyConnStr}" for the connection string -- which I declare in the INIT of the app, and which I would program to load dynamically when deploying.

hth,

Hank

[Jeff_Stone]

Hank,

Thanks for the reply. The error is the same even with "readwrite" removed. I have never worked with virtual tables. What did you mean "you can use that SELECT to populate the grid directly"? As mentioned above, when I used the following commands, the grid populated correctly but was not editable:
m_deals = lianja.getelementbyID("gDealList") //get the Grid ID
m_deals.addItems("select chosen,long_name,filename,settle_dt from deallist597") //populate the Grid

Is there a different way of populating the grid with SELECT?

I have never heard of or used VIRTUALTABLE before. I looked at the Lianja documentation on it but I'm confused as to how I would employ VIRTUALTABLE any differently than what I did with the SQL command that does populate the grid but was not editable. Would I create the virtualtable first and then SELECT from that?

tia

Jeff

[hmischel@diligentsystems.com]

Hi Jeff,

I started out looking at it the same way you did. Virtualtables handle the connectstring to the SQL Server backend and greatly simplify updating your data.
I'll look for an example that I use and post it a little later.

Herb

[yvonne.milne]

Hi Jeff,

Have you thought of using a standard Grid Section? (I know you'd like to have a checkbox rather than a combobox for the logical field - we've got your ticket for that one). If you 'Hide header' on the Grid Section, you can have a Canvas above it with your other controls and the two will blend together (note: Header shows in Development mode and is hidden in Runtime mode). If the Grid Section itself is 'Readonly' = False, but all columns apart from your logical 'Chosen' field are set to 'Readonly' = True (double-click on the column header to set the attributes for individual grid colums), then only that column will be editable. Any columns from the table not required can be Removed (right-click on column header). The data in the Grid itself can be restricted using the grid.filter property. For example, in my screenshot I use the southwind!products table in the Grid Section called section1 and I could do this to only show Category 2 products:

oGrid = Lianja.get("section1").grid
oGrid.filter = "categoryid = 2"

Note the Canvas Section TreeGrid does not have in-column editing, so you would need to change the Chosen field using scripting in, for example, the Click event.

[Jeff_Stone]

Hi Yvonne,

We considered the approach you outlined previously. Our problem is our clients want on OptionGroup and some other fields placed to the side of the grid. Because Lianja default sections take up the entire width of a page, we couldn't figure any other way to meet there wishes than to use a canvas or customized section.

Thanks,

Jeff

[yvonne.milne]

Hi Jeff,

In that case, you might want to consider using a custom Navigation Panel - maybe not available when you first looked at the standard Grid Section. Your Navigation Panel could be based on a Custom UI Page with a Canvas and appear along side the Grid Section. The example_customnavpanel App in the distribution has an example Navigation Panel based on a Page with standard sections; my screenshot below shows a Page with a Canvas section. Just build the Page you want in a new App, giving it a unique Page name and use the 'Save in the Page Library' button to make it available to other Apps.




Yvonne

[Jeff_Stone]

Hi Yvonne,

That may do the trick. I will play for a bit. Thanks very much for the suggestion.

Regards,

Jeff

(Incidentally, I noticed that when a checkbox is used with the header above it, the checkbox itself is left aligned relative to the header. Esthetically, it might look nicer if it were centered underneath the header.)