Hi Graham, The following (nonsense) example works:
getProp foo[bar] answer bar return "hello world" end foo setProp foo[bar] theData answer theData pass foo end foo You can use only one index, i.e. the setProp/getProp handlers are one-dimensional. An additional parameter contains the data that the property is being set to. Use the target to find out which control's property is being set. -- Best regards, Mark Schonewille Economy-x-Talk Consulting and Software Engineering Homepage: http://economy-x-talk.com Twitter: http://twitter.com/xtalkprogrammer KvK: 50277553 Get the extIco2Png external for LiveCode here http://qery.us/1w6 On 2 apr 2012, at 12:13, Graham Samuel wrote: > For the very first time in a pretty long career as a LiveCode coder, I'm > trying to make sense of DataGrids, which I see were a heroic effort to extend > LiveCode - with a very sophisticated implementation and literally hundreds of > pages of documentation. AFAIK it was done by Trevor deVore - I am deeply > impressed, even as I stumble. > > I am trying to implement some spreadsheet-like behaviour and have fallen more > or less at the first fence during the lesson on Page 94 "How do I get > Aggregate Values for Columns?". > > I can make the example work if I follow it exactly. It depends on a getProp > handler the first line of which is: > > getprop uSumOfColumn [pColumn] > > I would like to multiply two columns using this as a starting point, so I > would like to refer to two columns in my getProp handler. However when I look > up getProp in the LC documentation, I don't see that getProp can take any > parameters at all, certainly not an array reference, so my attempt to extend > this structure with a line like > > getProp usMultipleOfColumns [pColumn1] [ pColumn2] > > can't be compiled - putting a comma in between the parameters (if that's what > they are) doesn't help. As you see I have no idea what I'm doing. My question > is, how does the syntax of the original getProp handler work? How is the bit > in square brackets allowed, and why isn't it featured in the LC > documentation? If I did want to provide a getProp handler with the names of > two different columns, how would I do it? I do realise there are much more > pedestrian ways of achieving what I want, but it seems important to > understand the mechanism shown in the DataGrid docs. > > Ignorantly > > Graham _______________________________________________ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
