Filter: add reference counting for dive-site mode

The dive-site-edit and dive-site-table tabs both put the filter
into a special dive-site mode. When switching between both, it
could happen that the one got its show befor the other got
its hide event.

Thus, the first would start dive-site filtering and the second
stop it. Now the app was not in filter mode even though it should.

To solve this problem, add reference counting for the filter's
dive-site mode. In both tabs call the enter/exit functions
on show/hide. In the dive-site-table tab, when the selection
changes, use a set function that doesn't modify the reference count.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

1 files changed, 9 insertions, 0 deletions

diff --git a/qt-models/filtermodels.h b/qt-models/filtermodels.h
index b91b91a04..b726c2d28 100644
--- a/qt-models/filtermodels.h
+++ b/qt-models/filtermodels.h
@@ -70,6 +70,7 @@ slots:
 	void myInvalidate();
 	void clearFilter();
 	void startFilterDiveSites(QVector<dive_site *> ds);
+	void setFilterDiveSite(QVector<dive_site *> ds);
 	void stopFilterDiveSites();
 	void filterChanged(const QModelIndex &from, const QModelIndex &to, const QVector<int> &roles);
 	void resetModel(DiveTripModelBase::Layout layout);
@@ -86,6 +87,14 @@ private:
 	QVector<dive_site *> dive_sites;
 	void countsChanged();
 	FilterData filterData;
+
+	// We use ref-counting for the dive site mode. The reason is that when switching
+	// between two tabs that both need dive site mode, the following course of
+	// events may happen:
+	//	1) The new tab appears -> enter dive site mode.
+	//	2) The old tab gets its hide() signal -> exit dive site mode.
+	// The filter is now not in dive site mode, even if it should
+	int diveSiteRefCount;
 };
 
 #endif