Port tooltips to KToolTipWidget

Use the new KToolTipWidget class (introduced by kwidgetsaddons 5.30) as backend of ToolTipManager.
FileMetaDataToolTip becomes a simple widget used as content of the tooltip.

It is now possible to actually use the metadata widget shown inside the tooltips.
Tooltips are now functional on Wayland as well.

More information about KToolTipWidget in https://git.reviewboard.kde.org/r/129648/

BUG: 352276
BUG: 371223
FIXED-IN: 17.04.0

Closes T4980
Differential Revision: D4449

4 files changed, 21 insertions, 100 deletions

diff --git a/src/views/tooltips/filemetadatatooltip.cpp b/src/views/tooltips/filemetadatatooltip.cpp
index 0d58717d4..2fbba8b9c 100644
--- a/src/views/tooltips/filemetadatatooltip.cpp
+++ b/src/views/tooltips/filemetadatatooltip.cpp
@@ -47,9 +47,6 @@ FileMetaDataToolTip::FileMetaDataToolTip(QWidget* parent) :
     m_name(0),
     m_fileMetaDataWidget(0)
 {
-    setAttribute(Qt::WA_TranslucentBackground);
-    setWindowFlags(Qt::ToolTip | Qt::FramelessWindowHint | Qt::NoDropShadowWindowHint);
-
     // Create widget for file preview
     m_preview = new QLabel(this);
     m_preview->setAlignment(Qt::AlignTop);
@@ -161,19 +158,3 @@ KFileItemList FileMetaDataToolTip::items() const
     return m_fileMetaDataWidget->items();
 }
 
-void FileMetaDataToolTip::paintEvent(QPaintEvent* event)
-{
-    QStylePainter painter(this);
-    QStyleOptionFrame option;
-    option.init(this);
-    painter.drawPrimitive(QStyle::PE_PanelTipLabel, option);
-    painter.end();
-
-    QWidget::paintEvent(event);
-}
-
-void FileMetaDataToolTip::showEvent(QShowEvent *)
-{
-    KWindowEffects::enableBlurBehind(winId(), true, mask());
-}
-
diff --git a/src/views/tooltips/filemetadatatooltip.h b/src/views/tooltips/filemetadatatooltip.h
index 379b025c8..1738e386c 100644
--- a/src/views/tooltips/filemetadatatooltip.h
+++ b/src/views/tooltips/filemetadatatooltip.h
@@ -37,8 +37,8 @@ namespace Baloo {
 #endif
 
 /**
- * @brief Tooltip, that shows the meta information and a preview of one
- *        or more files.
+ * @brief Widget that shows the meta information and a preview of one
+ *        or more files inside a KToolTipWidget.
  */
 class FileMetaDataToolTip : public QWidget
 {
@@ -69,10 +69,6 @@ signals:
      */
     void metaDataRequestFinished(const KFileItemList& items);
 
-protected:
-    virtual void paintEvent(QPaintEvent* event) Q_DECL_OVERRIDE;
-    virtual void showEvent(QShowEvent *) Q_DECL_OVERRIDE;
-
 private:
     QLabel* m_preview;
     QLabel* m_name;
diff --git a/src/views/tooltips/tooltipmanager.cpp b/src/views/tooltips/tooltipmanager.cpp
index 404d6801c..d19e98c81 100644
--- a/src/views/tooltips/tooltipmanager.cpp
+++ b/src/views/tooltips/tooltipmanager.cpp
@@ -24,18 +24,22 @@
 #include <KIO/JobUiDelegate>
 #include <KIO/PreviewJob>
 #include <KJobWidgets>
+#include <KToolTipWidget>
 
 #include <QApplication>
 #include <QDesktopWidget>
 #include <QLayout>
 #include <QStyle>
 #include <QTimer>
+#include <QWindow>
 
 ToolTipManager::ToolTipManager(QWidget* parent) :
     QObject(parent),
     m_showToolTipTimer(0),
     m_contentRetrievalTimer(0),
+    m_transientParent(0),
     m_fileMetaDataToolTip(0),
+    m_tooltipWidget(new KToolTipWidget()),
     m_toolTipRequested(false),
     m_metaDataRequested(false),
     m_appliedWaitCursor(false),
@@ -62,11 +66,9 @@ ToolTipManager::ToolTipManager(QWidget* parent) :
 
 ToolTipManager::~ToolTipManager()
 {
-    delete m_fileMetaDataToolTip;
-    m_fileMetaDataToolTip = 0;
 }
 
-void ToolTipManager::showToolTip(const KFileItem& item, const QRectF& itemRect)
+void ToolTipManager::showToolTip(const KFileItem& item, const QRectF& itemRect, QWindow *transientParent)
 {
     hideToolTip();
 
@@ -75,10 +77,12 @@ void ToolTipManager::showToolTip(const KFileItem& item, const QRectF& itemRect)
     m_itemRect.adjust(-m_margin, -m_margin, m_margin, m_margin);
     m_item = item;
 
+    m_transientParent = transientParent;
+
     // Only start the retrieving of the content, when the mouse has been over this
     // item for 200 milliseconds. This prevents a lot of useless preview jobs and
     // meta data retrieval, when passing rapidly over a lot of items.
-    Q_ASSERT(!m_fileMetaDataToolTip);
+    delete m_fileMetaDataToolTip;
     m_fileMetaDataToolTip = new FileMetaDataToolTip();
     connect(m_fileMetaDataToolTip, &FileMetaDataToolTip::metaDataRequestFinished,
             this, &ToolTipManager::slotMetaDataRequestFinished);
@@ -100,14 +104,7 @@ void ToolTipManager::hideToolTip()
     m_metaDataRequested = false;
     m_showToolTipTimer->stop();
     m_contentRetrievalTimer->stop();
-
-    if (m_fileMetaDataToolTip) {
-        m_fileMetaDataToolTip->hide();
-        // Do not delete the tool tip immediately to prevent crashes when
-        // QCoreApplication tries to deliver an 'Enter' event to it, see bug 310579.
-        m_fileMetaDataToolTip->deleteLater();
-        m_fileMetaDataToolTip = 0;
-    }
+    m_tooltipWidget->hideLater();
 }
 
 void ToolTipManager::startContentRetrieval()
@@ -200,68 +197,9 @@ void ToolTipManager::showToolTip()
         return;
     }
 
-    const QRect screen = QApplication::desktop()->screenGeometry(QCursor::pos());
-
-    // Restrict tooltip size to current screen size when needed.
-    // Because layout controlling widget doesn't respect widget's maximumSize property
-    // (correct me if I'm wrong), we need to let layout do its work, then manually change
-    // geometry if resulting widget doesn't fit the screen.
-
-    // Step #1 - make sizeHint return calculated tooltip size
-    m_fileMetaDataToolTip->layout()->setSizeConstraint(QLayout::SetFixedSize);
+    // Adjust the size to get a proper sizeHint()
     m_fileMetaDataToolTip->adjustSize();
-    QSize size = m_fileMetaDataToolTip->sizeHint();
-
-    // Step #2 - correct tooltip size when needed
-    if (size.width() > screen.width()) {
-        size.setWidth(screen.width());
-    }
-    if (size.height() > screen.height()) {
-        size.setHeight(screen.height());
-    }
-
-    // m_itemRect defines the area of the item, where the tooltip should be
-    // shown. Per default the tooltip is shown centered at the bottom.
-    // It must be assured that:
-    // - the content is fully visible
-    // - the content is not drawn inside m_itemRect
-    const bool hasRoomToLeft  = (m_itemRect.left()   - size.width()  - m_margin >= screen.left());
-    const bool hasRoomToRight = (m_itemRect.right()  + size.width()  + m_margin <= screen.right());
-    const bool hasRoomAbove   = (m_itemRect.top()    - size.height() - m_margin >= screen.top());
-    const bool hasRoomBelow   = (m_itemRect.bottom() + size.height() + m_margin <= screen.bottom());
-    if (!hasRoomAbove && !hasRoomBelow && !hasRoomToLeft && !hasRoomToRight) {
-        return;
-    }
-
-    int x, y;
-    if (hasRoomBelow || hasRoomAbove) {
-        x = qMax(screen.left(), m_itemRect.center().x() - size.width() / 2);
-        if (x + size.width() >= screen.right()) {
-            x = screen.right() - size.width() + 1;
-        }
-        if (hasRoomBelow) {
-            y = m_itemRect.bottom() + m_margin;
-        } else {
-            y = m_itemRect.top() - size.height() - m_margin;
-        }
-    } else {
-        Q_ASSERT(hasRoomToLeft || hasRoomToRight);
-        if (hasRoomToRight) {
-            x = m_itemRect.right() + m_margin;
-        } else {
-            x = m_itemRect.left() - size.width() - m_margin;
-        }
-        // Put the tooltip at the bottom of the screen. The x-coordinate has already
-        // been adjusted, so that no overlapping with m_itemRect occurs.
-        y = screen.bottom() - size.height() + 1;
-    }
-
-    // Step #3 - Alter tooltip geometry
-    m_fileMetaDataToolTip->setFixedSize(size);
-    m_fileMetaDataToolTip->layout()->setSizeConstraint(QLayout::SetNoConstraint);
-    m_fileMetaDataToolTip->move(QPoint(x, y));
-    m_fileMetaDataToolTip->show();
-
+    m_tooltipWidget->showBelow(m_itemRect, m_fileMetaDataToolTip, m_transientParent);
     m_toolTipRequested = false;
 }
 
diff --git a/src/views/tooltips/tooltipmanager.h b/src/views/tooltips/tooltipmanager.h
index f6d8b8f26..58fe68763 100644
--- a/src/views/tooltips/tooltipmanager.h
+++ b/src/views/tooltips/tooltipmanager.h
@@ -26,7 +26,9 @@
 #include <KFileItem>
 
 class FileMetaDataToolTip;
+class KToolTipWidget;
 class QTimer;
+class QWindow;
 
 /**
  * @brief Manages the tooltips for an item view.
@@ -47,9 +49,9 @@ public:
      * Triggers the showing of the tooltip for the item \p item
      * where the item has the maximum boundaries of \p itemRect.
      * The tooltip manager takes care that the tooltip is shown
-     * slightly delayed.
+     * slightly delayed and with a proper \p transientParent.
      */
-    void showToolTip(const KFileItem& item, const QRectF& itemRect);
+    void showToolTip(const KFileItem& item, const QRectF& itemRect, QWindow *transientParent);
 
     /**
      * Hides the currently shown tooltip.
@@ -72,7 +74,11 @@ private:
     /// the tooltip content like preview and meta data gets started.
     QTimer* m_contentRetrievalTimer;
 
+    /// Transient parent of the tooltip, mandatory on Wayland.
+    QWindow* m_transientParent;
+
     FileMetaDataToolTip* m_fileMetaDataToolTip;
+    QScopedPointer<KToolTipWidget> m_tooltipWidget;
 
     bool m_toolTipRequested;
     bool m_metaDataRequested;