remove duplicated code and use CListHelpers::UpDownKey().
Some variable types had to be changed to avoid typecasts, as
a result (int) casts to foo.size() had to be added :-)
Origin commit data
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Commit: ed7eaafbcb
Author: Stefan Seyfried <seife@tuxbox-git.slipkontur.de>
Date: 2016-01-16 (Sat, 16 Jan 2016)
this can be used to factor out duplicate code implementations
from all the various channel-, bouquet-, eventlists etc...
Origin commit data
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Commit: ec4aa07e17
Author: Stefan Seyfried <seife@tuxbox-git.slipkontur.de>
Date: 2016-01-16 (Sat, 16 Jan 2016)
