5 files changed, 66 insertions, 1 deletions

diff --git a/src/kitemviews/kitemlistcontroller.cpp b/src/kitemviews/kitemlistcontroller.cpp
index b4d28047e..aea59c711 100644
--- a/src/kitemviews/kitemlistcontroller.cpp
+++ b/src/kitemviews/kitemlistcontroller.cpp
@@ -830,6 +830,7 @@ bool KItemListController::dragMoveEvent(QGraphicsSceneDragDropEvent *event, cons
             if (!m_autoActivationTimer->isActive() && m_autoActivationTimer->interval() >= 0) {
                 m_autoActivationTimer->setProperty("index", index);
                 m_autoActivationTimer->start();
+                newHoveredWidget->startActivateSoonAnimation(m_autoActivationTimer->remainingTime());
             }
         } else {
             m_autoActivationTimer->stop();
diff --git a/src/kitemviews/kitemlistwidget.cpp b/src/kitemviews/kitemlistwidget.cpp
index c4fa1f2cc..4c9f25986 100644
--- a/src/kitemviews/kitemlistwidget.cpp
+++ b/src/kitemviews/kitemlistwidget.cpp
@@ -438,6 +438,11 @@ QPixmap KItemListWidget::createDragPixmap(const QStyleOptionGraphicsItem *option
     return pixmap;
 }
 
+void KItemListWidget::startActivateSoonAnimation(int timeUntilActivation)
+{
+    Q_UNUSED(timeUntilActivation)
+}
+
 void KItemListWidget::dataChanged(const QHash<QByteArray, QVariant> &current, const QSet<QByteArray> &roles)
 {
     Q_UNUSED(current)
diff --git a/src/kitemviews/kitemlistwidget.h b/src/kitemviews/kitemlistwidget.h
index 55d924719..fdfe5e78a 100644
--- a/src/kitemviews/kitemlistwidget.h
+++ b/src/kitemviews/kitemlistwidget.h
@@ -188,6 +188,12 @@ public:
      */
     virtual QPixmap createDragPixmap(const QStyleOptionGraphicsItem *option, QWidget *widget = nullptr);
 
+    /**
+     * Starts an animation that makes clear that the item will be activated soon.
+     * @param timeUntilActivation time in milliseconds until the item will activate
+     */
+    virtual void startActivateSoonAnimation(int timeUntilActivation);
+
 Q_SIGNALS:
     void roleEditingCanceled(int index, const QByteArray &role, const QVariant &value);
     void roleEditingFinished(int index, const QByteArray &role, const QVariant &value);
diff --git a/src/kitemviews/kstandarditemlistwidget.cpp b/src/kitemviews/kstandarditemlistwidget.cpp
index 2a28d198a..b534338ce 100644
--- a/src/kitemviews/kstandarditemlistwidget.cpp
+++ b/src/kitemviews/kstandarditemlistwidget.cpp
@@ -24,6 +24,7 @@
 #include <QGraphicsView>
 #include <QPixmapCache>
 #include <QStyleOption>
+#include <QVariantAnimation>
 
 // #define KSTANDARDITEMLISTWIDGET_DEBUG
 
@@ -589,6 +590,50 @@ QPixmap KStandardItemListWidget::createDragPixmap(const QStyleOptionGraphicsItem
     return clippedPixmap;
 }
 
+void KStandardItemListWidget::startActivateSoonAnimation(int timeUntilActivation)
+{
+    if (m_activateSoonAnimation) {
+        m_activateSoonAnimation->stop(); // automatically DeleteWhenStopped
+    }
+
+    m_activateSoonAnimation = new QVariantAnimation{this};
+    m_activateSoonAnimation->setStartValue(0.0);
+    m_activateSoonAnimation->setEndValue(1.0);
+    m_activateSoonAnimation->setDuration(timeUntilActivation);
+
+    const QVariant originalIconName{data()["iconName"]};
+    connect(m_activateSoonAnimation, &QVariantAnimation::valueChanged, this, [originalIconName, this](const QVariant &value) {
+        auto progress = value.toFloat();
+
+        QVariant wantedIconName;
+        if (progress < 0.333) {
+            wantedIconName = "folder-open";
+        } else if (progress < 0.666) {
+            wantedIconName = originalIconName;
+        } else {
+            wantedIconName = "folder-open";
+        }
+
+        QHash<QByteArray, QVariant> itemData{data()};
+        if (itemData["iconName"] != wantedIconName) {
+            itemData.insert("iconName", wantedIconName);
+            setData(itemData);
+            invalidateIconCache();
+        }
+    });
+
+    connect(m_activateSoonAnimation, &QObject::destroyed, this, [originalIconName, this]() {
+        QHash<QByteArray, QVariant> itemData{data()};
+        if (itemData["iconName"] == "folder-open") {
+            itemData.insert("iconName", originalIconName);
+            setData(itemData);
+            invalidateIconCache();
+        }
+    });
+
+    m_activateSoonAnimation->start(QAbstractAnimation::DeleteWhenStopped);
+}
+
 KItemListWidgetInformant *KStandardItemListWidget::createInformant()
 {
     return new KStandardItemListWidgetInformant();
@@ -736,7 +781,9 @@ void KStandardItemListWidget::styleOptionChanged(const KItemListStyleOption &cur
 
 void KStandardItemListWidget::hoveredChanged(bool hovered)
 {
-    Q_UNUSED(hovered)
+    if (!hovered && m_activateSoonAnimation) {
+        m_activateSoonAnimation->stop(); // automatically DeleteWhenStopped
+    }
     m_dirtyLayout = true;
 }
 
diff --git a/src/kitemviews/kstandarditemlistwidget.h b/src/kitemviews/kstandarditemlistwidget.h
index 06bf0529a..5afadd8cd 100644
--- a/src/kitemviews/kstandarditemlistwidget.h
+++ b/src/kitemviews/kstandarditemlistwidget.h
@@ -17,6 +17,7 @@
 class KItemListRoleEditor;
 class KItemListStyleOption;
 class KItemListView;
+class QVariantAnimation;
 
 /**
  * @brief standard implementation of the ItemList widget informant for use with KStandardItemListView and KStandardItemModel.
@@ -103,6 +104,8 @@ public:
     QRectF expansionToggleRect() const override;
     QRectF selectionToggleRect() const override;
     QPixmap createDragPixmap(const QStyleOptionGraphicsItem *option, QWidget *widget = nullptr) override;
+    /** @see KItemListWidget::startActivateSoonAnimation() */
+    void startActivateSoonAnimation(int timeUntilActivation) override;
 
     static KItemListWidgetInformant *createInformant();
 
@@ -282,6 +285,9 @@ private:
     KItemListRoleEditor *m_roleEditor;
     KItemListRoleEditor *m_oldRoleEditor;
 
+    /** @see startActivateSoonAnimation() */
+    QPointer<QVariantAnimation> m_activateSoonAnimation;
+
     friend class KStandardItemListWidgetInformant; // Accesses private static methods to be able to
                                                    // share a common layout calculation
 };