From c1a086da25e746ddf7dbe7f212d3cc61a9174035 Mon Sep 17 00:00:00 2001
From: Peter Penz <peter.penz19@gmail.com>
Date: Mon, 29 Jun 2009 19:32:39 +0000
Subject: [PATCH] Fixed issue that the scroll position is reset if the focus of
 the itemview changes.

BUG: 197951

svn path=/trunk/KDE/kdebase/apps/; revision=989236
---
 src/dolphincolumnwidget.cpp     |  4 +---
 src/dolphindetailsview.cpp      |  4 +---
 src/dolphiniconsview.cpp        |  4 +---
 src/dolphinviewautoscroller.cpp | 11 +++++++++++
 src/dolphinviewautoscroller.h   |  8 ++++++++
 5 files changed, 22 insertions(+), 9 deletions(-)

diff --git a/src/dolphincolumnwidget.cpp b/src/dolphincolumnwidget.cpp
index e85c9491b..c8bff0290 100644
--- a/src/dolphincolumnwidget.cpp
+++ b/src/dolphincolumnwidget.cpp
@@ -491,9 +491,7 @@ void DolphinColumnWidget::selectionChanged(const QItemSelection& selected, const
 void DolphinColumnWidget::currentChanged(const QModelIndex& current, const QModelIndex& previous)
 {
     QListView::currentChanged(current, previous);
-    if (current.isValid() && !m_autoScroller->isActive()) {
-        scrollTo(current);
-    }
+    m_autoScroller->handleCurrentIndexChange(current, previous);
 }
 
 void DolphinColumnWidget::slotEntered(const QModelIndex& index)
diff --git a/src/dolphindetailsview.cpp b/src/dolphindetailsview.cpp
index ad362914a..aa65ff6bc 100644
--- a/src/dolphindetailsview.cpp
+++ b/src/dolphindetailsview.cpp
@@ -429,9 +429,7 @@ void DolphinDetailsView::wheelEvent(QWheelEvent* event)
 void DolphinDetailsView::currentChanged(const QModelIndex& current, const QModelIndex& previous)
 {
     QTreeView::currentChanged(current, previous);
-    if (current.isValid() && !m_autoScroller->isActive()) {
-        scrollTo(current);
-    }
+    m_autoScroller->handleCurrentIndexChange(current, previous);
 
     // Stay consistent with QListView: When changing the current index by key presses,
     // also change the selection.
diff --git a/src/dolphiniconsview.cpp b/src/dolphiniconsview.cpp
index 4c7e9180f..183197ffb 100644
--- a/src/dolphiniconsview.cpp
+++ b/src/dolphiniconsview.cpp
@@ -302,9 +302,7 @@ void DolphinIconsView::leaveEvent(QEvent* event)
 void DolphinIconsView::currentChanged(const QModelIndex& current, const QModelIndex& previous)
 {
     KCategorizedView::currentChanged(current, previous);
-    if (current.isValid() && !m_autoScroller->isActive()) {
-        scrollTo(current);
-    }
+    m_autoScroller->handleCurrentIndexChange(current, previous);
 }
 
 void DolphinIconsView::resizeEvent(QResizeEvent* event)
diff --git a/src/dolphinviewautoscroller.cpp b/src/dolphinviewautoscroller.cpp
index 75dab3214..ea9b1a2d6 100644
--- a/src/dolphinviewautoscroller.cpp
+++ b/src/dolphinviewautoscroller.cpp
@@ -54,6 +54,17 @@ bool DolphinViewAutoScroller::isActive() const
     return m_timer->isActive();
 }
 
+void DolphinViewAutoScroller::handleCurrentIndexChange(const QModelIndex& current,
+                                                       const QModelIndex& previous)
+{
+    // When the autoscroller is inactive and a key has been pressed, it must be
+    // assured that the current item stays visible. The check whether the previous
+    // item is valid is important because of #197951.
+    if (current.isValid() && previous.isValid() && !isActive()) {
+        m_itemView->scrollTo(current);
+    }
+}
+
 bool DolphinViewAutoScroller::eventFilter(QObject* watched, QEvent* event)
 {
     if (watched == m_itemView->viewport()) {
diff --git a/src/dolphinviewautoscroller.h b/src/dolphinviewautoscroller.h
index 3827b2326..c95155f58 100644
--- a/src/dolphinviewautoscroller.h
+++ b/src/dolphinviewautoscroller.h
@@ -23,6 +23,7 @@
 #include <QObject>
 
 class QAbstractItemView;
+class QModelIndex;
 class QTimer;
 
 /**
@@ -40,6 +41,13 @@ public:
     virtual ~DolphinViewAutoScroller();
     bool isActive() const;
 
+    /**
+     * Must be invoked by the parent item view, when QAbstractItemView::currentChanged()
+     * has been called. Assures that the current item stays visible when it has been
+     * changed by the keyboard.
+     */
+    void handleCurrentIndexChange(const QModelIndex& current, const QModelIndex& previous);
+
 protected:
     virtual bool eventFilter(QObject* watched, QEvent* event);
 
-- 
2.47.3