Dive list: make filter model aware of its source

The data-flow from C-core to list-view is as follows:

C-core --> DiveTripModel --> MultiSortFilterModel --> DiveListView

The control-flow, on the other hand, differs as DiveListView
accesses both MultiSortFilterModel and DiveTripModel, whereas
MultiSortFilterModel is mostly unaware of its source model.

This is in principle legitimate, as the MultiSortFilterModel might
be used for different sources. In our particular case, this is
not so. MultiSortFilterModel is written for a particular use case.

Therefore, model control-flow follow after data-flow: Let MultiSortFilterModel
set its own source model and DiveListView access the MultiSortFilterModel,
which then manages its source model.

This is not bike-shedding, but will enable a more flexible and
higher-performance sorting.

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

5 files changed, 18 insertions, 12 deletions

diff --git a/desktop-widgets/divelistview.cpp b/desktop-widgets/divelistview.cpp
index c01a6189a..30364a8eb 100644
--- a/desktop-widgets/divelistview.cpp
+++ b/desktop-widgets/divelistview.cpp
@@ -33,12 +33,7 @@ DiveListView::DiveListView(QWidget *parent) : QTreeView(parent), mouseClickSelec
 	setItemDelegate(new DiveListDelegate(this));
 	setUniformRowHeights(true);
 	setItemDelegateForColumn(DiveTripModel::RATING, new StarWidgetsDelegate(this));
-	MultiFilterSortModel *model = MultiFilterSortModel::instance();
-	model->setSortRole(DiveTripModel::SORT_ROLE);
-	model->setFilterKeyColumn(-1); // filter all columns
-	model->setFilterCaseSensitivity(Qt::CaseInsensitive);
-	model->setSourceModel(DiveTripModel::instance());
-	setModel(model);
+	setModel(MultiFilterSortModel::instance());
 
 	setSortingEnabled(false);
 	setContextMenuPolicy(Qt::DefaultContextMenu);
@@ -503,8 +498,7 @@ void DiveListView::reload(DiveTripModel::Layout layout, bool forceSort)
 	header()->setSectionsClickable(true);
 	connect(header(), SIGNAL(sectionPressed(int)), this, SLOT(headerClicked(int)), Qt::UniqueConnection);
 
-	DiveTripModel *tripModel = DiveTripModel::instance();
-	tripModel->setLayout(layout);	// Note: setLayout() resets the whole model
+	MultiFilterSortModel::instance()->setLayout(layout);
 
 	if (!forceSort)
 		return;
diff --git a/qt-models/divetripmodel.cpp b/qt-models/divetripmodel.cpp
index 14bc744f6..0194a312f 100644
--- a/qt-models/divetripmodel.cpp
+++ b/qt-models/divetripmodel.cpp
@@ -320,9 +320,6 @@ DiveTripModel::DiveTripModel(QObject *parent) :
 	connect(&diveListNotifier, &DiveListNotifier::divesSelected, this, &DiveTripModel::divesSelected);
 	connect(&diveListNotifier, &DiveListNotifier::divesDeselected, this, &DiveTripModel::divesDeselected);
 	connect(&diveListNotifier, &DiveListNotifier::currentDiveChanged, this, &DiveTripModel::currentDiveChanged);
-
-	// Update trip headers if filter finished
-	connect(MultiFilterSortModel::instance(), &MultiFilterSortModel::filterFinished, this, &DiveTripModel::filterFinished);
 }
 
 int DiveTripModel::columnCount(const QModelIndex&) const
diff --git a/qt-models/divetripmodel.h b/qt-models/divetripmodel.h
index fb826eec1..b372a981f 100644
--- a/qt-models/divetripmodel.h
+++ b/qt-models/divetripmodel.h
@@ -55,6 +55,7 @@ public:
 	int rowCount(const QModelIndex &parent) const;
 	QModelIndex index(int row, int column, const QModelIndex &parent) const;
 	QModelIndex parent(const QModelIndex &index) const;
+	void filterFinished();
 signals:
 	// The propagation of selection changes is complex.
 	// The control flow of dive-selection goes:
@@ -74,7 +75,6 @@ private slots:
 	void divesSelected(dive_trip *trip, const QVector<dive *> &dives);
 	void divesDeselected(dive_trip *trip, const QVector<dive *> &dives);
 	void currentDiveChanged();
-	void filterFinished();
 private:
 	// The model has up to two levels. At the top level, we have either trips or dives
 	// that do not belong to trips. Such a top-level item is represented by the "Item"
diff --git a/qt-models/filtermodels.cpp b/qt-models/filtermodels.cpp
index ce0c2528c..857c5d698 100644
--- a/qt-models/filtermodels.cpp
+++ b/qt-models/filtermodels.cpp
@@ -562,6 +562,16 @@ MultiFilterSortModel::MultiFilterSortModel(QObject *parent) : QSortFilterProxyMo
 	divesDisplayed(0),
 	curr_dive_site(NULL)
 {
+	setSortRole(DiveTripModel::SORT_ROLE);
+	setFilterKeyColumn(-1); // filter all columns
+	setFilterCaseSensitivity(Qt::CaseInsensitive);
+	setSourceModel(DiveTripModel::instance());
+}
+
+void MultiFilterSortModel::setLayout(DiveTripModel::Layout layout)
+{
+	DiveTripModel *tripModel = DiveTripModel::instance();
+	tripModel->setLayout(layout);	// Note: setLayout() resets the whole model
 }
 
 void MultiFilterSortModel::divesAdded(const QVector<dive *> &dives)
@@ -656,6 +666,8 @@ void MultiFilterSortModel::myInvalidate()
 
 	invalidateFilter();
 
+	// Tell the dive trip model to update the displayed-counts
+	DiveTripModel::instance()->filterFinished();
 	emit filterFinished();
 
 #if !defined(SUBSURFACE_MOBILE)
diff --git a/qt-models/filtermodels.h b/qt-models/filtermodels.h
index f962386a1..f579df1a9 100644
--- a/qt-models/filtermodels.h
+++ b/qt-models/filtermodels.h
@@ -2,6 +2,8 @@
 #ifndef FILTERMODELS_H
 #define FILTERMODELS_H
 
+#include "divetripmodel.h" // For DiveTripModel::Layout. TODO: remove in due course
+
 #include <QStringListModel>
 #include <QSortFilterProxyModel>
 #include <stdint.h>
@@ -132,6 +134,7 @@ slots:
 	void startFilterDiveSite(struct dive_site *ds);
 	void stopFilterDiveSite();
 	void filterChanged(const QModelIndex &from, const QModelIndex &to, const QVector<int> &roles);
+	void setLayout(DiveTripModel::Layout layout);
 
 signals:
 	void filterFinished();