Scrolling of DataGrid driven by Database on IOS

[Michael Doub]

Thanks for your response Terry, but what I meant by being directly loaded into the database was when the app directly filled in the data from the data base upon receiving the 

     on GetDataForLine pLine, @pOutData

message.  The only thing that I have seen so far is the  setting dgNumberofRecordsto turn on the use of GetDataForLine.

     set the dgNumberOfRecords of group "Data Grid" to sRecordCount

I can see where this would allow a calculation of dgFormattedHeight if the rows were fixed.   I am trying to understand how this should work when the row height is variable.



On 2011-11-14, at 6:21 PM, Terry Judd wrote:

> 
> On 15/11/2011, at 09:22 AM, Michael Doub wrote:
> 
>> Does anyone have an example of a DataGrid form with non fixed height rows being directly loaded from the database that is also hooked up to the IOS scroller?
>> 
>> Yes I am being kind of specific here.   I have found examples for large datasets using data grids, but none of which have variable hight rows.  Hooking it up to the IOS scroller is interesting because I don't know how one would figure out the "contentRect" of the scroller.
> 
> I create a locked group containing the datagrid that is set to the dimensions. I then populate the datagrid (usually with data fetched from a database via a PHP script and converted to an array) and set its height based on ALL the records it contains.
> So, for example if my datagrid is name myData_DG, I place it in a locked and sized group called myData. And do something like this...
> 
> set the dgData of grp "myData_DG" to tData
> set the height of grp "myData_DG" to the max((the dgFormattedheight of grp "myData_DG"),(the height of grp "myData"))
> 
> then to setup the scroller, something like...
> 
> local pScrollerID, pScrollerGrp
> iphoneControlCreate "scroller"
> put the result into pScrollerId
> put "myData" into pScrollerGrp
> put the rect of grp pScrollerGrp into theGridRect
> iphoneControlSet pScrollerId, "rect", theGridRect
> # setup other scroller properties here
> # now setup the scroller ContectRect
> put (the dgFormattedHeight of group "myData_DG") into tHeight
> put the width of group pScrollerGrp into tWidth
> iphoneControlSet pScrollerId, "contentRect", (0,0, tWidth, tHeight)
> 
> If you're using a table datagrid then you'll need to create a separate 'header' (I use another datagrid for this) and 'link' it to the datagrid containing the data so that it will respond when you click the column names in the header to sort the datagrid.
> 
> My datagrids all have fixed line heights so if you're toggling rows and changing line heights in the process I guess you might need to reset the height of the datagrid using...
> 
> set the height of grp "myData_DG" to the max((the dgFormattedheight of grp "myData_DG"),(the height of grp "myData"))
> 
> and reset the scroller's content rect using...
> 
> put (the dgFormattedHeight of group "myData_DG") into tHeight
> put the width of group pScrollerGrp into tWidth
> iphoneControlSet pScrollerId, "contentRect", (0,0, tWidth, tHeight)
> 
> Not sure what toggling rows will do to the actual scroll value of the scroller however (could be messy).
> 
> Terry...
> 
>> 
>> Thanks
>>  Mike
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> 
> Dr Terry Judd
> Senior Lecturer in Medical Education
> Medical Eduction Unit
> Faculty of Medicine, Dentistry & Health Sciences
> The University of Melbourne
> 
> 
> 
> 
> 
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