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How to Deal with a Canvas Reference Change


Question:

How to deal with the canvas reference change that took place with the shift from release 10.0 to 10.1?

Answer:

The change of the declarations concerning the referencing of a canvas in some event declarations had to be performed in order to support future compiler versions and to improve C++ compatibility. The following declarations are affected by the change:

'var' removed:

'const' removed: As a consequence you have to apply a few changes in your source code when updating from any release of the SDL Suite previous to 10.1 to a release 10.1 or higher. If you do not apply the changes, two effects will arise: (1) the compiler may complain about an invalid reference and will ask whether to remove the reference (say NO); (2) your program may generate a "general access error" and crash on certain actions.

In any case you should search through your source code for expressions such as 'var XYXYXY: TCanvas' and 'const XYXYXY: TCanvas'. The best way to do this is to use the following regular expression in your search term: 'var .*TCanvas' (or 'const .*TCanvas') and remove the 'var' (or the 'const') substring, respectively.


Last Update: 2023-Feb-06