From 28e97e75556e50c33fb064a60725ab7937ef5440 Mon Sep 17 00:00:00 2001
From: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
Date: Thu, 28 Nov 2019 21:55:26 +0100
Subject: [PATCH] Cleanup: remove DiveListView::expandedRows member variable

The QList served as backing store for backupExpandedRows()
and restoreExpandedRows(). However, these always came in
pairs in the same scope. There is no reason to store the
expanded rows over a longer time.

Therefore, return the expanded rows from backupExpandedRows()
and take them as argument in restoreExpandedRows(). Morover
replace the QList<int> by the much lighter std::vector<int>.
We certainly don't need copy-on-write, reference-counting and
immutability of iterators in this case.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
---
 desktop-widgets/divelistview.cpp | 20 +++++++++++---------
 desktop-widgets/divelistview.h   |  5 ++---
 2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/desktop-widgets/divelistview.cpp b/desktop-widgets/divelistview.cpp
index a4b5ad282..ee0c1c98f 100644
--- a/desktop-widgets/divelistview.cpp
+++ b/desktop-widgets/divelistview.cpp
@@ -135,7 +135,7 @@ void DiveListView::calculateInitialColumnWidth(int col)
 void DiveListView::setColumnWidths()
 {
 	QSettings settings;
-	backupExpandedRows();
+	std::vector<int> expandedRows = backupExpandedRows();
 	settings.beginGroup("ListWidget");
 	/* if no width are set, use the calculated width for each column;
 	 * for that to work we need to temporarily expand all rows */
@@ -150,7 +150,7 @@ void DiveListView::setColumnWidths()
 			setColumnWidth(i, initialColumnWidths[i]);
 	}
 	settings.endGroup();
-	restoreExpandedRows();
+	restoreExpandedRows(expandedRows);
 	setColumnWidth(lastVisibleColumn(), 10);
 }
 
@@ -165,18 +165,19 @@ int DiveListView::lastVisibleColumn()
 	return lastColumn;
 }
 
-void DiveListView::backupExpandedRows()
+std::vector<int> DiveListView::backupExpandedRows()
 {
-	expandedRows.clear();
+	std::vector<int> expandedRows;
 	for (int i = 0; i < model()->rowCount(); i++)
 		if (isExpanded(model()->index(i, 0)))
 			expandedRows.push_back(i);
+	return expandedRows;
 }
 
-void DiveListView::restoreExpandedRows()
+void DiveListView::restoreExpandedRows(const std::vector<int> &expandedRows)
 {
 	setAnimated(false);
-	Q_FOREACH (const int &i, expandedRows)
+	for (int i: expandedRows)
 		setExpanded(model()->index(i, 0), true);
 	setAnimated(true);
 }
@@ -437,13 +438,14 @@ void DiveListView::sortIndicatorChanged(int i, Qt::SortOrder order)
 		sortByColumn(i, order);
 	} else {
 		// clear the model, repopulate with new indexes.
-		if (currentLayout == DiveTripModelBase::TREE)
-			backupExpandedRows();
+		std::vector<int> expandedRows;
+		if(currentLayout == DiveTripModelBase::TREE)
+			expandedRows = backupExpandedRows();
 		currentLayout = newLayout;
 		resetModel();
 		sortByColumn(i, order);
 		if (newLayout == DiveTripModelBase::TREE)
-			restoreExpandedRows();
+			restoreExpandedRows(expandedRows);
 	}
 }
 
diff --git a/desktop-widgets/divelistview.h b/desktop-widgets/divelistview.h
index d4954ee86..ce3021b3f 100644
--- a/desktop-widgets/divelistview.h
+++ b/desktop-widgets/divelistview.h
@@ -69,7 +69,6 @@ private:
 	void setSelection(const QRect &rect, QItemSelectionModel::SelectionFlags flags) override;
 	void selectAll() override;
 	void selectionChangeDone();
-	QList<int> expandedRows;
 	DiveTripModelBase::Layout currentLayout;
 	QModelIndex contextMenuIndex;
 	bool dontEmitDiveChangedSignal;
@@ -80,8 +79,8 @@ private:
 	void merge_trip(const QModelIndex &a, const int offset);
 	void setColumnWidths();
 	void calculateInitialColumnWidth(int col);
-	void backupExpandedRows();
-	void restoreExpandedRows();
+	std::vector<int> backupExpandedRows();
+	void restoreExpandedRows(const std::vector<int> &);
 	int lastVisibleColumn();
 	void selectTrip(dive_trip *trip);
 	void updateLastImageTimeOffset(int offset);