Add gas consumption statistic for selected dives

We already did a list of gases and volume consumed for the selected dive
on the Dive Info tab, but did not provide that same data on the Stats tab
for all the selected dives.

I arbitrary limited this to eight gases (as the list can get quite long
when you select a lot of dives). The gases are sorted by volume consumed.

Fixes #535

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/helpers.h b/helpers.h
index 445e9135c..392dcb5ac 100644
--- a/helpers.h
+++ b/helpers.h
@@ -33,6 +33,7 @@ QString get_dive_date_string(timestamp_t when);
 QString get_short_dive_date_string(timestamp_t when);
 QString get_trip_date_string(timestamp_t when, int nr);
 QString uiLanguage(QLocale *callerLoc);
+void selectedDivesGasUsed(QVector<QPair<QString, int> > &gasUsed);
 
 #define M_OR_FT(_m, _f) ((prefs.units.length == units::METERS) ? ((_m) * 1000) : (feet_to_mm(_f)))