Add smaller statusbar and set it as default

- Statusbar has three modes: Small, FullWidth and Disabled
- FullWidth is the original statusbar
- Small is the new default statusbar
  - This statusbar overlays on top of the items instead of taking space
  - It changes size according to content
- Disabled turns statusbar completely off
- Zoom slider and space information is only shown in full-width statusbar
  - Space information is now always on
- If user navigates with keyboard, or scrolls to selection, the scrolling will take the statusbar into account
  - This makes sure the statusbar does not cover any items

Related discussion: https://invent.kde.org/system/dolphin/-/issues/50

4 files changed, 40 insertions, 1 deletions

diff --git a/src/kitemviews/kitemlistview.cpp b/src/kitemviews/kitemlistview.cpp
index 369415f1b..c56785c36 100644
--- a/src/kitemviews/kitemlistview.cpp
+++ b/src/kitemviews/kitemlistview.cpp
@@ -106,6 +106,7 @@ KItemListView::KItemListView(QGraphicsWidget *parent)
     , m_header(nullptr)
     , m_headerWidget(nullptr)
     , m_indicatorAnimation(nullptr)
+    , m_statusBarOffset(0)
     , m_dropIndicator()
     , m_sizeHintResolver(nullptr)
 {
@@ -192,7 +193,7 @@ qreal KItemListView::scrollOffset() const
 
 qreal KItemListView::maximumScrollOffset() const
 {
-    return m_layouter->maximumScrollOffset();
+    return m_layouter->maximumScrollOffset() + m_statusBarOffset;
 }
 
 void KItemListView::setItemOffset(qreal offset)
@@ -554,6 +555,9 @@ void KItemListView::scrollToItem(int index, ViewItemPosition viewItemPosition)
         const qreal headerHeight = m_headerWidget->size().height();
         viewGeometry.adjust(0, headerHeight, 0, 0);
     }
+    if (m_statusBarOffset != 0) {
+        viewGeometry.adjust(0, 0, 0, -m_statusBarOffset);
+    }
     QRectF currentRect = itemRect(index);
 
     if (layoutDirection() == Qt::RightToLeft && scrollOrientation() == Qt::Horizontal) {
@@ -829,6 +833,16 @@ void KItemListView::paint(QPainter *painter, const QStyleOptionGraphicsItem *opt
     }
 }
 
+void KItemListView::setStatusBarOffset(int offset)
+{
+    if (m_statusBarOffset != offset) {
+        m_statusBarOffset = offset;
+        if (m_layouter) {
+            m_layouter->setStatusBarOffset(offset);
+        }
+    }
+}
+
 QVariant KItemListView::itemChange(GraphicsItemChange change, const QVariant &value)
 {
     if (change == QGraphicsItem::ItemSceneHasChanged && scene()) {
diff --git a/src/kitemviews/kitemlistview.h b/src/kitemviews/kitemlistview.h
index 30ce4d871..7fb3344b4 100644
--- a/src/kitemviews/kitemlistview.h
+++ b/src/kitemviews/kitemlistview.h
@@ -302,6 +302,12 @@ public:
 
     void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget = nullptr) override;
 
+    /**
+     * Set the bottom offset for moving the view so that the small overlayed statusbar
+     * won't cover any items by accident.
+     */
+    void setStatusBarOffset(int offset);
+
 Q_SIGNALS:
     void scrollOrientationChanged(Qt::Orientation current, Qt::Orientation previous);
     void scrollOffsetChanged(qreal current, qreal previous);
@@ -776,6 +782,8 @@ private:
 
     QPropertyAnimation *m_indicatorAnimation;
 
+    int m_statusBarOffset;
+
     // When dragging items into the view where the sort-role of the model
     // is empty, a visual indicator should be shown during dragging where
     // the dropping will happen. This indicator is specified by an index
diff --git a/src/kitemviews/private/kitemlistviewlayouter.cpp b/src/kitemviews/private/kitemlistviewlayouter.cpp
index 99a95d98c..3ed2343a8 100644
--- a/src/kitemviews/private/kitemlistviewlayouter.cpp
+++ b/src/kitemviews/private/kitemlistviewlayouter.cpp
@@ -40,6 +40,7 @@ KItemListViewLayouter::KItemListViewLayouter(KItemListSizeHintResolver *sizeHint
     , m_groupHeaderHeight(0)
     , m_groupHeaderMargin(0)
     , m_itemInfos()
+    , m_statusBarOffset(0)
 {
     Q_ASSERT(m_sizeHintResolver);
 }
@@ -341,6 +342,13 @@ void KItemListViewLayouter::markAsDirty()
     m_dirty = true;
 }
 
+void KItemListViewLayouter::setStatusBarOffset(int offset)
+{
+    if (m_statusBarOffset != offset) {
+        m_statusBarOffset = offset;
+    }
+}
+
 #ifndef QT_NO_DEBUG
 bool KItemListViewLayouter::isDirty()
 {
@@ -378,6 +386,7 @@ void KItemListViewLayouter::doLayout()
         itemSize.transpose();
         itemMargin.transpose();
         size.transpose();
+        size.rwidth() -= m_statusBarOffset;
 
         if (grouped) {
             // In the horizontal scrolling case all groups are aligned
diff --git a/src/kitemviews/private/kitemlistviewlayouter.h b/src/kitemviews/private/kitemlistviewlayouter.h
index 77d59c947..fed541a4c 100644
--- a/src/kitemviews/private/kitemlistviewlayouter.h
+++ b/src/kitemviews/private/kitemlistviewlayouter.h
@@ -154,6 +154,12 @@ public:
         return m_columnCount;
     }
 
+    /**
+     * Set the bottom offset for moving the view so that the small overlayed statusbar
+     * won't cover any items by accident.
+     */
+    void setStatusBarOffset(int offset);
+
 #ifndef QT_NO_DEBUG
     /**
      * @return True if the layouter has been marked as dirty and hence has
@@ -219,6 +225,8 @@ private:
     };
     QVector<ItemInfo> m_itemInfos;
 
+    int m_statusBarOffset;
+
     friend class KItemListControllerTest;
 };