Cache group view geometry -- speed up instance view by caching sizes of stuff

This commit is contained in:
Petr Mrázek 2014-07-12 12:49:07 +02:00
parent 6a8984a21d
commit d570037331
2 changed files with 22 additions and 10 deletions

View File

@ -8,6 +8,7 @@
#include <QPersistentModelIndex>
#include <QDrag>
#include <QMimeData>
#include <QCache>
#include <QScrollBar>
#include "Group.h"
@ -68,6 +69,7 @@ void GroupView::rowsAboutToBeRemoved(const QModelIndex &parent, int start, int e
void GroupView::updateGeometries()
{
geometryCache.clear();
int previousScroll = verticalScrollBar()->value();
QMap<QString, Group *> cats;
@ -658,6 +660,13 @@ QRect GroupView::geometryRect(const QModelIndex &index) const
return QRect();
}
int row = index.row();
if(geometryCache.contains(row))
{
return *geometryCache[row];
}
else
{
const Group *cat = category(index);
QPair<int, int> pos = categoryInternalPosition(index);
int x = pos.first;
@ -667,8 +676,9 @@ QRect GroupView::geometryRect(const QModelIndex &index) const
out.setTop(cat->verticalPosition() + cat->headerHeight() + 5 + categoryInternalRowTop(index));
out.setLeft(m_spacing + x * (itemWidth() + m_spacing));
out.setSize(itemDelegate()->sizeHint(viewOptions(), index));
const_cast<QCache<int, QRect>&>(geometryCache).insert(row, new QRect(out));
return out;
}
}
/*

View File

@ -3,6 +3,7 @@
#include <QListView>
#include <QLineEdit>
#include <QScrollBar>
#include <QCache>
struct GroupViewRoles
{
@ -128,6 +129,7 @@ private: /* variables */
QItemSelectionModel::SelectionFlag m_ctrlDragSelectionFlag;
QPoint m_lastDragPosition;
int m_spacing = 5;
QCache<int, QRect> geometryCache;
private: /* methods */
QPair<int, int> categoryInternalPosition(const QModelIndex &index) const;