#include <QClipboard>
#include <QColor>
#include <QPainter>
+#include <QScrollBar>
#include <QIcon>
IconManager::IconManager(QAbstractItemView* parent, DolphinSortFilterProxyModel* model) :
QObject(parent),
m_showPreview(false),
+ m_clearItemQueues(true),
m_view(parent),
m_previewTimer(0),
+ m_scrollAreaTimer(0),
m_previewJobs(),
m_dolphinModel(0),
m_proxyModel(model),
m_cutItemsCache(),
- m_previews()
+ m_previews(),
+ m_pendingItems(),
+ m_dispatchedItems()
{
Q_ASSERT(m_view->iconSize().isValid()); // each view must provide its current icon size
this, SLOT(updateCutItems()));
m_previewTimer = new QTimer(this);
+ m_previewTimer->setSingleShot(true);
connect(m_previewTimer, SIGNAL(timeout()), this, SLOT(dispatchPreviewQueue()));
+
+ // Whenever the scrollbar values have been changed, the pending previews should
+ // be reordered in a way that the previews for the visible items are generated
+ // first. The reordering is done with a small delay, so that during moving the
+ // scrollbars the CPU load is kept low.
+ m_scrollAreaTimer = new QTimer(this);
+ m_scrollAreaTimer->setSingleShot(true);
+ m_scrollAreaTimer->setInterval(200);
+ connect(m_scrollAreaTimer, SIGNAL(timeout()),
+ this, SLOT(resumePreviews()));
+ connect(m_view->horizontalScrollBar(), SIGNAL(valueChanged(int)),
+ this, SLOT(pausePreviews()));
+ connect(m_view->verticalScrollBar(), SIGNAL(valueChanged(int)),
+ this, SLOT(pausePreviews()));
}
IconManager::~IconManager()
{
- killJobs();
+ killPreviewJobs();
+ m_pendingItems.clear();
+ m_dispatchedItems.clear();
}
return;
}
- killJobs();
+ killPreviewJobs();
m_cutItemsCache.clear();
+ m_pendingItems.clear();
+ m_dispatchedItems.clear();
KFileItemList itemList;
const int rowCount = m_dolphinModel->rowCount();
return;
}
- const QRect visibleArea = m_view->viewport()->rect();
-
// Order the items in a way that the preview for the visible items
// is generated first, as this improves the feeled performance a lot.
+ const QRect visibleArea = m_view->viewport()->rect();
KFileItemList orderedItems;
- foreach (const KFileItem &item, items) {
+ foreach (const KFileItem& item, items) {
const QModelIndex dirIndex = m_dolphinModel->indexForItem(item);
const QModelIndex proxyIndex = m_proxyModel->mapFromSource(dirIndex);
const QRect itemRect = m_view->visualRect(proxyIndex);
if (itemRect.intersects(visibleArea)) {
orderedItems.insert(0, item);
+ m_pendingItems.insert(0, item.url());
} else {
orderedItems.append(item);
+ m_pendingItems.append(item.url());
}
}
- const QSize size = m_view->iconSize();
- KIO::PreviewJob* job = KIO::filePreview(orderedItems, 128, 128);
- connect(job, SIGNAL(gotPreview(const KFileItem&, const QPixmap&)),
- this, SLOT(addToPreviewQueue(const KFileItem&, const QPixmap&)));
- connect(job, SIGNAL(finished(KJob*)),
- this, SLOT(slotPreviewJobFinished(KJob*)));
-
- m_previewJobs.append(job);
- m_previewTimer->start(200);
+ startPreviewJob(orderedItems);
}
void IconManager::addToPreviewQueue(const KFileItem& item, const QPixmap& pixmap)
preview.url = item.url();
preview.pixmap = pixmap;
m_previews.append(preview);
+
+ m_dispatchedItems.append(item.url());
}
void IconManager::slotPreviewJobFinished(KJob* job)
{
const int index = m_previewJobs.indexOf(job);
m_previewJobs.removeAt(index);
+
+ if ((m_previewJobs.count() == 0) && m_clearItemQueues) {
+ m_pendingItems.clear();
+ m_dispatchedItems.clear();
+ }
}
void IconManager::updateCutItems()
}
}
+void IconManager::pausePreviews()
+{
+ foreach (KJob* job, m_previewJobs) {
+ Q_ASSERT(job != 0);
+ job->suspend();
+ }
+ m_scrollAreaTimer->start();
+}
+
+void IconManager::resumePreviews()
+{
+ // Before creating new preview jobs the m_pendingItems queue must be
+ // cleaned up by removing the already dispatched items. Implementation
+ // note: The order of the m_dispatchedItems queue and the m_pendingItems
+ // queue is usually equal. So even when having a lot of elements the
+ // nested loop is no performance bottle neck, as the inner loop is only
+ // entered once in most cases.
+ foreach (const KUrl& url, m_dispatchedItems) {
+ QList<KUrl>::iterator begin = m_pendingItems.begin();
+ QList<KUrl>::iterator end = m_pendingItems.end();
+ for (QList<KUrl>::iterator it = begin; it != end; ++it) {
+ if ((*it) == url) {
+ m_pendingItems.erase(it);
+ break;
+ }
+ }
+ }
+ m_dispatchedItems.clear();
+
+ // Create a new preview job for the remaining items.
+ // Order the items in a way that the preview for the visible items
+ // is generated first, as this improves the feeled performance a lot.
+ const QRect visibleArea = m_view->viewport()->rect();
+ KFileItemList orderedItems;
+ foreach (const KUrl& url, m_pendingItems) {
+ const QModelIndex dirIndex = m_dolphinModel->indexForUrl(url);
+ const KFileItem item = m_dolphinModel->itemForIndex(dirIndex);
+ const QModelIndex proxyIndex = m_proxyModel->mapFromSource(dirIndex);
+ const QRect itemRect = m_view->visualRect(proxyIndex);
+ if (itemRect.intersects(visibleArea)) {
+ orderedItems.insert(0, item);
+ } else {
+ orderedItems.append(item);
+ }
+ }
+
+ // Kill all suspended preview jobs. Usually when a preview job
+ // has been finished, slotPreviewJobFinished() clears all item queues.
+ // This is not wanted in this case, as a new job is created afterwards
+ // for m_pendingItems.
+ m_clearItemQueues = false;
+ killPreviewJobs();
+ m_clearItemQueues = true;
+
+ startPreviewJob(orderedItems);
+}
+
void IconManager::replaceIcon(const KUrl& url, const QPixmap& pixmap)
{
Q_ASSERT(url.isValid());
}
}
-void IconManager::killJobs()
+void IconManager::startPreviewJob(const KFileItemList& items)
+{
+ if (items.count() == 0) {
+ return;
+ }
+
+ const QSize size = m_view->iconSize();
+ KIO::PreviewJob* job = KIO::filePreview(items, 128, 128);
+ connect(job, SIGNAL(gotPreview(const KFileItem&, const QPixmap&)),
+ this, SLOT(addToPreviewQueue(const KFileItem&, const QPixmap&)));
+ connect(job, SIGNAL(finished(KJob*)),
+ this, SLOT(slotPreviewJobFinished(KJob*)));
+
+ m_previewJobs.append(job);
+ m_previewTimer->start(200);
+}
+
+void IconManager::killPreviewJobs()
{
foreach (KJob* job, m_previewJobs) {
Q_ASSERT(job != 0);
* Per default a preview is generated for each item.
* Additionally the clipboard is checked for cut items.
* The icon state for cut items gets dimmed automatically.
+ *
+ * The following strategy is used when creating previews:
+ * - The previews for currently visible items are created before
+ * the previews for invisible items.
+ * - If the user changes the visible area by using the scrollbars,
+ * all pending previews get paused. As soon as the user stays
+ * on the same position for a short delay, the previews are
+ * resumed. Also in this case the previews for the visible items
+ * are generated first.
*/
class IconManager : public QObject
{
void updateCutItems();
/**
- * Dispatches the preview queue m_previews block by block within
+ * Dispatches the preview queue block by block within
* time slices.
*/
void dispatchPreviewQueue();
+ /**
+ * Pauses all preview jobs and invokes IconManager::resumePreviews()
+ * after a short delay. Is invoked as soon as the user has moved
+ * a scrollbar.
+ */
+ void pausePreviews();
+
+ /**
+ * Resumes the previews that have been paused after moving the
+ * scrollbar. The previews for the current visible area are
+ * generated first.
+ */
+ void resumePreviews();
+
private:
/**
* Replaces the icon of the item with the \a url by the preview pixmap
*/
void limitToSize(QPixmap& icon, const QSize& maxSize);
+ /**
+ * Starts a new preview job for the items \a to m_previewJobs
+ * and triggers the preview timer.
+ */
+ void startPreviewJob(const KFileItemList& items);
+
/** Kills all ongoing preview jobs. */
- void killJobs();
+ void killPreviewJobs();
private:
- /**
- * Remembers the pixmap for an item specified by an URL.
- */
+ /** Remembers the pixmap for an item specified by an URL. */
struct ItemInfo
{
KUrl url;
bool m_showPreview;
+ /**
+ * True, if m_pendingItems and m_dispatchedItems should be
+ * cleared when the preview jobs have been finished.
+ */
+ bool m_clearItemQueues;
+
QAbstractItemView* m_view;
QTimer* m_previewTimer;
+ QTimer* m_scrollAreaTimer;
QList<KJob*> m_previewJobs;
DolphinModel* m_dolphinModel;
DolphinSortFilterProxyModel* m_proxyModel;
QList<ItemInfo> m_cutItemsCache;
QList<ItemInfo> m_previews;
+
+ /**
+ * Contains the URLs of all items where a preview must be generated, but
+ * where the preview job has not dispatched the items yet.
+ */
+ QList<KUrl> m_pendingItems;
+
+ /**
+ * Containts the URLs of all items, where a preview has already been
+ * generated by the preview jobs.
+ */
+ QList<KUrl> m_dispatchedItems;
};
inline bool IconManager::showPreview() const
projects / dolphin.git / commitdiff