Initial draft for bringing back the "Folders" panel

The folders panel has been adjusted to use the new view-engine.
A lot of things don't work yet, but are mostly minor issues that
should be fixable during the next 10 days.

6 files changed, 107 insertions, 22 deletions

diff --git a/src/kitemviews/kfileitemlistview.cpp b/src/kitemviews/kfileitemlistview.cpp
index a7fa27f0d..b0ffd3c20 100644
--- a/src/kitemviews/kfileitemlistview.cpp
+++ b/src/kitemviews/kfileitemlistview.cpp
@@ -65,6 +65,8 @@ KFileItemListView::KFileItemListView(QGraphicsWidget* parent) :
     m_updateIconSizeTimer->setInterval(ShortInterval);
     connect(m_updateIconSizeTimer, SIGNAL(timeout()), this, SLOT(updateIconSize()));
 
+    setVisibleRoles(QList<QByteArray>() << "name");
+
     updateMinimumRolesWidths();
 }
 
@@ -302,7 +304,8 @@ void KFileItemListView::initializeItemListWidget(KItemListWidget* item)
     default:            Q_ASSERT(false); break;
     }
 
-    fileItemListWidget->setAlternatingBackgroundColors(m_itemLayout == DetailsLayout);
+    fileItemListWidget->setAlternatingBackgroundColors(m_itemLayout == DetailsLayout &&
+                                                       visibleRoles().count() > 1);
 }
 
 bool KFileItemListView::itemSizeHintUpdateRequired(const QSet<QByteArray>& changedRoles) const
@@ -332,6 +335,8 @@ void KFileItemListView::onModelChanged(KItemModelBase* current, KItemModelBase*
     m_modelRolesUpdater = new KFileItemModelRolesUpdater(static_cast<KFileItemModel*>(current), this);
     const int size = styleOption().iconSize;
     m_modelRolesUpdater->setIconSize(QSize(size, size));
+
+    applyRolesToModel();
 }
 
 void KFileItemListView::onScrollOrientationChanged(Qt::Orientation current, Qt::Orientation previous)
@@ -360,6 +365,19 @@ void KFileItemListView::onVisibleRolesChanged(const QList<QByteArray>& current,
     Q_UNUSED(current);
     Q_UNUSED(previous);
     applyRolesToModel();
+
+    if (m_itemLayout == DetailsLayout) {
+        // Only enable the alternating background colors if more than one role
+        // is visible
+        const int previousCount = previous.count();
+        const int currentCount = current.count();
+        if ((previousCount <= 1 && currentCount > 1) || (previousCount > 1 && currentCount <= 1)) {
+            const bool enabled = (currentCount > 1);
+            foreach (KItemListWidget* widget, visibleItemListWidgets()) {
+                widget->setAlternatingBackgroundColors(enabled);
+            }
+        }
+    }
 }
 
 void KFileItemListView::onStyleOptionChanged(const KItemListStyleOption& current, const KItemListStyleOption& previous)
@@ -410,6 +428,9 @@ void KFileItemListView::slotSortRoleChanged(const QByteArray& current, const QBy
 
 void KFileItemListView::triggerVisibleIndexRangeUpdate()
 {
+    if (!model()) {
+        return;
+    }
     m_modelRolesUpdater->setPaused(true);
     m_updateVisibleIndexRangeTimer->start();
 }
@@ -439,6 +460,9 @@ void KFileItemListView::updateVisibleIndexRange()
 
 void KFileItemListView::triggerIconSizeUpdate()
 {
+    if (!model()) {
+        return;
+    }
     m_modelRolesUpdater->setPaused(true);
     m_updateIconSizeTimer->start();
 }
@@ -494,6 +518,10 @@ QSizeF KFileItemListView::visibleRoleSizeHint(int index, const QByteArray& role)
 
 void KFileItemListView::updateLayoutOfVisibleItems()
 {
+    if (!model()) {
+        return;
+    }
+
     foreach (KItemListWidget* widget, visibleItemListWidgets()) {
         initializeItemListWidget(widget);
     }
@@ -528,6 +556,10 @@ void KFileItemListView::updateMinimumRolesWidths()
 
 void KFileItemListView::applyRolesToModel()
 {
+    if (!model()) {
+        return;
+    }
+
     Q_ASSERT(qobject_cast<KFileItemModel*>(model()));
     KFileItemModel* fileItemModel = static_cast<KFileItemModel*>(model());
 
diff --git a/src/kitemviews/kfileitemmodel.cpp b/src/kitemviews/kfileitemmodel.cpp
index d46bfc8da..363503b02 100644
--- a/src/kitemviews/kfileitemmodel.cpp
+++ b/src/kitemviews/kfileitemmodel.cpp
@@ -49,7 +49,7 @@ KFileItemModel::KFileItemModel(KDirLister* dirLister, QObject* parent) :
     m_groups(),
     m_rootExpansionLevel(-1),
     m_expandedUrls(),
-    m_restoredExpandedUrls()
+    m_urlsToExpand()
 {
     // Apply default roles that should be determined
     resetRoles();
@@ -431,9 +431,43 @@ QSet<KUrl> KFileItemModel::expandedUrls() const
     return m_expandedUrls;
 }
 
-void KFileItemModel::restoreExpandedUrls(const QSet<KUrl>& urls)
+void KFileItemModel::setExpanded(const QSet<KUrl>& urls)
 {
-    m_restoredExpandedUrls = urls;
+
+    const KDirLister* dirLister = m_dirLister.data();
+    if (!dirLister) {
+        return;
+    }
+
+    const int pos = dirLister->url().url().length();
+
+    // Assure that each sub-path of the URLs that should be
+    // expanded is added to m_urlsToExpand too. KDirLister
+    // does not care whether the parent-URL has already been
+    // expanded.
+    QSetIterator<KUrl> it1(urls);
+    while (it1.hasNext()) {
+        const KUrl& url = it1.next();
+
+        KUrl urlToExpand = dirLister->url();
+        const QStringList subDirs = url.url().mid(pos).split(QDir::separator());
+        for (int i = 0; i < subDirs.count(); ++i) {
+            urlToExpand.addPath(subDirs.at(i));
+            m_urlsToExpand.insert(urlToExpand);
+        }
+    }
+
+    // KDirLister::open() must called at least once to trigger an initial
+    // loading. The pending URLs that must be restored are handled
+    // in slotCompleted().
+    QSetIterator<KUrl> it2(m_urlsToExpand);
+    while (it2.hasNext()) {
+        const int idx = index(it2.next());
+        if (idx >= 0 && !isExpanded(idx)) {
+            setExpanded(idx, true);
+            break;
+        }
+    }
 }
 
 void KFileItemModel::onGroupedSortingChanged(bool current)
@@ -520,7 +554,7 @@ void KFileItemModel::resortAllItems()
 
 void KFileItemModel::slotCompleted()
 {
-    if (m_restoredExpandedUrls.isEmpty() && m_minimumUpdateIntervalTimer->isActive()) {
+    if (m_urlsToExpand.isEmpty() && m_minimumUpdateIntervalTimer->isActive()) {
         // dispatchPendingItems() will be called when the timer
         // has been expired.
         m_pendingEmitLoadingCompleted = true;
@@ -530,25 +564,26 @@ void KFileItemModel::slotCompleted()
     m_pendingEmitLoadingCompleted = false;
     dispatchPendingItemsToInsert();
 
-    if (!m_restoredExpandedUrls.isEmpty()) {
+    if (!m_urlsToExpand.isEmpty()) {
         // Try to find a URL that can be expanded.
         // Note that the parent folder must be expanded before any of its subfolders become visible.
         // Therefore, some URLs in m_restoredExpandedUrls might not be visible yet
         // -> we expand the first visible URL we find in m_restoredExpandedUrls.
-        foreach(const KUrl& url, m_restoredExpandedUrls) {
+        foreach(const KUrl& url, m_urlsToExpand) {
             const int index = m_items.value(url, -1);
             if (index >= 0) {
-                // We have found an expandable URL. Expand it and return - when
-                // the dir lister has finished, this slot will be called again.
-                m_restoredExpandedUrls.remove(url);
-                setExpanded(index, true);
-                return;
+                m_urlsToExpand.remove(url);
+                if (setExpanded(index, true)) {
+                    // The dir lister has been triggered. This slot will be called
+                    // again after the directory has been expanded.
+                    return;
+                }
             }
         }
 
         // None of the URLs in m_restoredExpandedUrls could be found in the model. This can happen
         // if these URLs have been deleted in the meantime.
-        m_restoredExpandedUrls.clear();
+        m_urlsToExpand.clear();
     }
 
     emit loadingCompleted();
diff --git a/src/kitemviews/kfileitemmodel.h b/src/kitemviews/kfileitemmodel.h
index b28887b2c..a049f6766 100644
--- a/src/kitemviews/kfileitemmodel.h
+++ b/src/kitemviews/kfileitemmodel.h
@@ -120,7 +120,11 @@ public:
     bool isExpanded(int index) const;
     bool isExpandable(int index) const;
     QSet<KUrl> expandedUrls() const;
-    void restoreExpandedUrls(const QSet<KUrl>& urls);
+
+    /**
+     * Expands all parent-items of each URL given by \a urls.
+     */
+    void setExpanded(const QSet<KUrl>& urls);
 
 signals:
     void loadingCompleted();
@@ -291,8 +295,9 @@ private:
     // Stores the URLs of the expanded folders.
     QSet<KUrl> m_expandedUrls;
 
-    // Stores the URLs which have to be expanded in order to restore a previous state of the model.
-    QSet<KUrl> m_restoredExpandedUrls;
+    // URLs that must be expanded. The expanding is initially triggered in setExpanded()
+    // and done step after step in slotCompleted().
+    QSet<KUrl> m_urlsToExpand;
 
     friend class KFileItemModelTest; // For unit testing
 };
diff --git a/src/kitemviews/kitemlistcontainer.cpp b/src/kitemviews/kitemlistcontainer.cpp
index d006e2c4d..8ca983acd 100644
--- a/src/kitemviews/kitemlistcontainer.cpp
+++ b/src/kitemviews/kitemlistcontainer.cpp
@@ -314,7 +314,14 @@ void KItemListContainer::updateSmoothScrollers(Qt::Orientation orientation)
 
 void KItemListContainer::initialize()
 {
-    if (!m_controller) {
+    if (m_controller) {
+        if (m_controller->model()) {
+            slotModelChanged(m_controller->model(), 0);
+        }
+        if (m_controller->view()) {
+            slotViewChanged(m_controller->view(), 0);
+        }
+    } else {
         m_controller = new KItemListController(this);
     }
 
diff --git a/src/kitemviews/kitemliststyleoption.cpp b/src/kitemviews/kitemliststyleoption.cpp
index f26b220bc..83af31202 100644
--- a/src/kitemviews/kitemliststyleoption.cpp
+++ b/src/kitemviews/kitemliststyleoption.cpp
@@ -19,13 +19,15 @@
 
 #include "kitemliststyleoption.h"
 
+#include <KIconLoader>
+
 KItemListStyleOption::KItemListStyleOption() :
     rect(),
     font(),
     fontMetrics(QFont()),
     palette(),
     margin(0),
-    iconSize(0)
+    iconSize(KIconLoader::SizeMedium)
 {
 }
 
diff --git a/src/kitemviews/kitemlistview.cpp b/src/kitemviews/kitemlistview.cpp
index 4ded4a93e..389069ce3 100644
--- a/src/kitemviews/kitemlistview.cpp
+++ b/src/kitemviews/kitemlistview.cpp
@@ -1196,7 +1196,7 @@ void KItemListView::setModel(KItemModelBase* model)
     }
 
     m_model = model;
-    m_layouter->setModel(model);
+    m_layouter->setModel(model);   
     m_grouped = model->groupedSorting();
 
     if (m_model) {
@@ -1231,7 +1231,7 @@ void KItemListView::doLayout(LayoutAnimationHint hint, int changedIndex, int cha
         m_layoutTimer->stop();
     }
 
-    if (m_model->count() < 0 || m_activeTransactions > 0) {
+    if (!m_model || m_model->count() < 0 || m_activeTransactions > 0) {
         return;
     }
 
@@ -1675,6 +1675,10 @@ void KItemListView::updateVisibleRolesSizes(const KItemRangeList& itemRanges)
 
 void KItemListView::updateVisibleRolesSizes()
 {
+    if (!m_model) {
+        return;
+    }
+
     const int itemCount = m_model->count();
     if (itemCount > 0) {
         updateVisibleRolesSizes(KItemRangeList() << KItemRange(0, itemCount));
@@ -1683,7 +1687,7 @@ void KItemListView::updateVisibleRolesSizes()
 
 void KItemListView::updateStretchedVisibleRolesSizes()
 {
-    if (!m_itemSize.isEmpty() || m_useHeaderWidths) {
+    if (!m_itemSize.isEmpty() || m_useHeaderWidths || m_visibleRoles.isEmpty()) {
         return;
     }
 
@@ -1692,7 +1696,7 @@ void KItemListView::updateStretchedVisibleRolesSizes()
     // size does not use the available view-size it the size of the
     // first role will get stretched.
     m_stretchedVisibleRolesSizes = m_visibleRolesSizes;
-    const QByteArray role = visibleRoles().first();
+    const QByteArray role = m_visibleRoles.first();
     QSizeF firstRoleSize = m_stretchedVisibleRolesSizes.value(role);
 
     QSizeF dynamicItemSize = m_itemSize;