4 files changed, 36 insertions, 3 deletions
diff --git a/qt-models/divetripmodel.cpp b/qt-models/divetripmodel.cpp
index 7c6655ba8..1281ed84c 100644
--- a/qt-models/divetripmodel.cpp
+++ b/qt-models/divetripmodel.cpp
@@ -964,10 +964,19 @@ QVariant DiveTripModelTree::data(const QModelIndex &index, int role) const
 		const Item &item = items[index.row()];
 		return std::find(item.dives.begin(), item.dives.end(), current_dive) != item.dives.end();
 	}
-	if (entry.trip)
+	if (entry.trip) {
 		return tripData(entry.trip, index.column(), role);
-	else
+	} else if (entry.dive) {
+#if defined(SUBSURFACE_MOBILE)
+		if (role == MobileListModel::TripAbove)
+			return tripInDirection(entry.dive, +1);
+		if (role == MobileListModel::TripBelow)
+			return tripInDirection(entry.dive, -1);
+#endif
 		return diveData(entry.dive, index.column(), role);
+	} else {
+		return QVariant();
+	}
 }
 
 // After a trip changed, the top level might need to be reordered.
@@ -1136,6 +1145,26 @@ static QVector<dive *> visibleDives(const QVector<dive *> &dives)
 	return res;
 }
 
+#ifdef SUBSURFACE_MOBILE
+int DiveTripModelTree::tripInDirection(const struct dive *d, int direction) const
+{
+	for (int i = 0; i < (int)items.size(); ++i) {
+		if (items[i].d_or_t.dive == d || (items[i].d_or_t.trip && findDiveInTrip(i, d) != -1)) {
+			// now walk in the direction given to find a trip
+			int offset = direction;
+			while (i + offset >= 0 && i + offset < (int)items.size()) {
+				if (items[i + offset].d_or_t.trip && (!d->divetrip || items[i + offset].d_or_t.trip->id != d->divetrip->id))
+					// we found a trip (and if the dive is already in a trip, we make sure this is a different trip)
+					return items[i + offset].d_or_t.trip->id;
+				offset += direction;
+			}
+			break;
+		}
+	}
+	return -1;
+}
+#endif
+
 void DiveTripModelTree::divesAdded(dive_trip *trip, bool newTrip, const QVector<dive *> &divesIn)
 {
 	QVector <dive *> dives = visibleDives(divesIn);
diff --git a/qt-models/divetripmodel.h b/qt-models/divetripmodel.h
index c5def254a..49fc3ce69 100644
--- a/qt-models/divetripmodel.h
+++ b/qt-models/divetripmodel.h
@@ -77,7 +77,6 @@ public:
 	// Used for sorting. This is a bit of a layering violation, as sorting should be performed
 	// by the higher-up QSortFilterProxyModel, but it makes things so much easier!
 	virtual bool lessThan(const QModelIndex &i1, const QModelIndex &i2) const = 0;
-
 signals:
 	// The propagation of selection changes is complex.
 	// The control flow of dive-selection goes:
@@ -120,6 +119,7 @@ public slots:
 
 public:
 	DiveTripModelTree(QObject *parent = nullptr);
+	int tripInDirection(const struct dive *d, int direction) const;
 private:
 	int rowCount(const QModelIndex &parent) const override;
 	void clearData() override;
diff --git a/qt-models/mobilelistmodel.cpp b/qt-models/mobilelistmodel.cpp
index 75753b12a..cbb6871b6 100644
--- a/qt-models/mobilelistmodel.cpp
+++ b/qt-models/mobilelistmodel.cpp
@@ -47,6 +47,8 @@ QHash<int, QByteArray> MobileListModelBase::roleNames() const
 	roles[FirstGasRole] = "firstGas";
 	roles[SelectedRole] = "selected";
 	roles[DiveInTripRole] = "diveInTrip";
+	roles[TripAbove] = "tripAbove";
+	roles[TripBelow] = "tripBelow";
 	return roles;
 }
 
diff --git a/qt-models/mobilelistmodel.h b/qt-models/mobilelistmodel.h
index 572a3b146..d00f26c62 100644
--- a/qt-models/mobilelistmodel.h
+++ b/qt-models/mobilelistmodel.h
@@ -55,6 +55,8 @@ public:
 		FirstGasRole,
 		SelectedRole,
 		DiveInTripRole,
+		TripAbove,
+		TripBelow,
 	};
 	QHash<int, QByteArray> roleNames() const override;
 protected: