A problem with Raster

[xueyue]

I would like a Raster to have the following function:
Suppose I draw to objects (say, two lines
[aRaster lineX0:Y0:X1...]), now if I click the first line
then the data associated with the line (in my case,
a line may represent a link of a transport network) can
be shown on another widget (e.g., on a Canvas), if I click
on the second line, then data associated with it can
be shown. I found
[aRaster setButton:Client:Message] is not enough since
we are unable to specify the client as the object we clicked on.
May be my understanding is not correct.
Anyone can help with this?

BTW: the following message is to Canvas developers:
I found the following functions are obviously not included in methods of
Canvas:
(1) The foreground and background color can not be
specified;
(2) text color can not be specified;

Thanks!


--
Dr Xueyue Huang
Center for Transport Studies
Imperial College
London SW7 2BU

(+44) 171 594 6037

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