4 files changed, 16 insertions, 41 deletions
diff --git a/qt-models/divetripmodel.cpp b/qt-models/divetripmodel.cpp
index ae6dfe651..64bb28533 100644
--- a/qt-models/divetripmodel.cpp
+++ b/qt-models/divetripmodel.cpp
@@ -357,22 +357,6 @@ QVariant DiveTripModelBase::headerData(int section, Qt::Orientation orientation,
 	return QVariant();
 }
 
-static std::unique_ptr<DiveTripModelBase> currentModel;
-DiveTripModelBase *DiveTripModelBase::instance()
-{
-	if (!currentModel)
-		resetModel(TREE);
-	return currentModel.get();
-}
-
-void DiveTripModelBase::resetModel(DiveTripModelBase::Layout layout)
-{
-	if (layout == TREE)
-		currentModel.reset(new DiveTripModelTree);
-	else
-		currentModel.reset(new DiveTripModelList);
-}
-
 // After resetting the model, the higher up model or view may call this
 // function to get informed on the current selection.
 // TODO: Currently, this reads and resets the selection. Make this more
diff --git a/qt-models/divetripmodel.h b/qt-models/divetripmodel.h
index 66af0a32a..eed6913cf 100644
--- a/qt-models/divetripmodel.h
+++ b/qt-models/divetripmodel.h
@@ -18,12 +18,6 @@ struct DiveFilter;
 // from DiveTripModelBase, which implements common features (e.g.
 // definition of the column types, access of data from the core
 // structures) and a common interface.
-//
-// The currently active model is set via DiveTripModelBase::resetModel().
-// This will create a new model. The model can be accessed with
-// DiveTripModelBase::instance(). A pointer obtained by instance()
-// is invalidated by a call to resetModel()! Yes, this is surprising
-// behavior, so care must be taken.
 class DiveTripModelBase : public QAbstractItemModel {
 	Q_OBJECT
 public:
@@ -63,15 +57,6 @@ public:
 		LIST,
 	};
 
-	// Functions implemented by base class
-	static DiveTripModelBase *instance();
-
-	// Reset the model using the given layout. After this call instance() will return
-	// a newly allocated object and the old model will have been destroyed! Thus, the
-	// caller is responsible for removing all references to any previous model obtained
-	// by instance().
-	static void resetModel(Layout layout);
-
 	// Call after having set the model to be informed of the current selection.
 	void initSelection();
 
diff --git a/qt-models/filtermodels.cpp b/qt-models/filtermodels.cpp
index 463276e13..d07de02c0 100644
--- a/qt-models/filtermodels.cpp
+++ b/qt-models/filtermodels.cpp
@@ -15,6 +15,7 @@ MultiFilterSortModel *MultiFilterSortModel::instance()
 
 MultiFilterSortModel::MultiFilterSortModel(QObject *parent) : QSortFilterProxyModel(parent)
 {
+	resetModel(DiveTripModelBase::TREE);
 	setFilterKeyColumn(-1); // filter all columns
 	setFilterRole(DiveTripModelBase::SHOWN_ROLE); // Let the proxy-model known that is has to react to change events involving SHOWN_ROLE
 	setFilterCaseSensitivity(Qt::CaseInsensitive);
@@ -22,19 +23,20 @@ MultiFilterSortModel::MultiFilterSortModel(QObject *parent) : QSortFilterProxyMo
 
 void MultiFilterSortModel::resetModel(DiveTripModelBase::Layout layout)
 {
-	DiveTripModelBase::resetModel(layout);
-	// DiveTripModelBase::resetModel() generates a new instance.
-	// Thus, the source model must be reset and the connections must be reset.
-	DiveTripModelBase *m = DiveTripModelBase::instance();
-	setSourceModel(m);
-	connect(m, &DiveTripModelBase::selectionChanged, this, &MultiFilterSortModel::selectionChangedSlot);
-	connect(m, &DiveTripModelBase::currentDiveChanged, this, &MultiFilterSortModel::currentDiveChangedSlot);
-	m->initSelection();
+	if (layout == DiveTripModelBase::TREE)
+		model.reset(new DiveTripModelTree);
+	else
+		model.reset(new DiveTripModelList);
+
+	setSourceModel(model.get());
+	connect(model.get(), &DiveTripModelBase::selectionChanged, this, &MultiFilterSortModel::selectionChangedSlot);
+	connect(model.get(), &DiveTripModelBase::currentDiveChanged, this, &MultiFilterSortModel::currentDiveChangedSlot);
+	model->initSelection();
 }
 
 void MultiFilterSortModel::clear()
 {
-	DiveTripModelBase::instance()->clear();
+	model->clear();
 }
 
 // Translate selection into local indexes and re-emit signal
@@ -68,5 +70,5 @@ bool MultiFilterSortModel::filterAcceptsRow(int source_row, const QModelIndex &s
 bool MultiFilterSortModel::lessThan(const QModelIndex &i1, const QModelIndex &i2) const
 {
 	// Hand sorting down to the source model.
-	return DiveTripModelBase::instance()->lessThan(i1, i2);
+	return model->lessThan(i1, i2);
 }
diff --git a/qt-models/filtermodels.h b/qt-models/filtermodels.h
index fef39e0d5..33d17791b 100644
--- a/qt-models/filtermodels.h
+++ b/qt-models/filtermodels.h
@@ -5,7 +5,10 @@
 #include "divetripmodel.h"
 
 #include <QSortFilterProxyModel>
+#include <memory>
 
+// This proxy model sits on top of either a DiveTripList or DiveTripTree model
+// and does filtering and/or sorting.
 class MultiFilterSortModel : public QSortFilterProxyModel {
 	Q_OBJECT
 public:
@@ -23,6 +26,7 @@ private slots:
 	void currentDiveChangedSlot(QModelIndex index);
 private:
 	MultiFilterSortModel(QObject *parent = 0);
+	std::unique_ptr<DiveTripModelBase> model;
 };
 
 #endif