New focusitem is not connected to the translate slot in splitview

If user changes focus from one item to a new one while the splitview
keyboard is open, the newly focused item is not connected to the
translate() slot. Thus, the item will not be kept "automatically"
visible above the keyboard when cursor position changes.

QCoeFepInputContext now holds a pointer to the last focus item and
disconnects the previous focus item from slot when new focus item
is set. Ensuring the visibility of the focus item needs to be done
asynchronously after reset() has been called from graphics scene,
to ensure that new focus item has been set.

The translation rules have been tweaked to support translation to
both directions (up|down). Previous implementation worked properly
only for upwards translation (new cursor position was assumed to
be lower than the existing one).

Task-number: QTBUG-21611
Reviewed-by: Miikka Heikkinen

2 files changed, 55 insertions, 24 deletions

diff --git a/src/gui/inputmethod/qcoefepinputcontext_p.h b/src/gui/inputmethod/qcoefepinputcontext_p.h
index 8ef9726..ad51b4b 100644
--- a/src/gui/inputmethod/qcoefepinputcontext_p.h
+++ b/src/gui/inputmethod/qcoefepinputcontext_p.h
@@ -136,6 +136,7 @@ private:
 private Q_SLOTS:
     void ensureInputCapabilitiesChanged();
     void translateInputWidget();
+    void ensureWidgetVisibility();
 
     // From MCoeFepAwareTextEditor
 public:
@@ -208,6 +209,7 @@ private:
     int m_splitViewResizeBy;
     Qt::WindowStates m_splitViewPreviousWindowStates;
     QRectF m_transformation;
+    QGraphicsItem *m_splitViewPreviousFocusItem; //can't use QPointer<> since QGraphicsItem is not a QObject.
 
     CAknCcpuSupport *m_ccpu;
     QAction *m_copyAction;
diff --git a/src/gui/inputmethod/qcoefepinputcontext_s60.cpp b/src/gui/inputmethod/qcoefepinputcontext_s60.cpp
index 3546079..bacf07a 100644
--- a/src/gui/inputmethod/qcoefepinputcontext_s60.cpp
+++ b/src/gui/inputmethod/qcoefepinputcontext_s60.cpp
@@ -382,6 +382,7 @@ QCoeFepInputContext::QCoeFepInputContext(QObject *parent)
       m_hasTempPreeditString(false),
       m_splitViewResizeBy(0),
       m_splitViewPreviousWindowStates(Qt::WindowNoState),
+      m_splitViewPreviousFocusItem(0),
       m_ccpu(0)
 {
     m_fepState->SetObjectProvider(this);
@@ -451,6 +452,11 @@ void QCoeFepInputContext::reset()
     if (m_cachedPreeditString.isEmpty() && !(currentHints & Qt::ImhNoPredictiveText))
         m_cachedPreeditString = m_preeditString;
     commitCurrentString(true);
+
+    // QGraphicsScene calls reset() when changing focus item. Unfortunately, the new focus item is
+    // set right after resetting the input context. Therefore, asynchronously call ensureWidgetVisibility().
+    if (S60->splitViewLastWidget)
+        QMetaObject::invokeMethod(this,"ensureWidgetVisibility", Qt::QueuedConnection);
 }
 
 void QCoeFepInputContext::ReportAknEdStateEvent(MAknEdStateObserver::EAknEdwinStateEvent aEventType)
@@ -793,9 +799,8 @@ void QCoeFepInputContext::resetSplitViewWidget(bool keepInputWidget)
 {
     QGraphicsView *gv = qobject_cast<QGraphicsView*>(S60->splitViewLastWidget);
 
-    if (!gv) {
+    if (!gv)
         return;
-    }
 
     QSymbianControl *symControl = static_cast<QSymbianControl*>(gv->effectiveWinId());
     symControl->CancelLongTapTimer();
@@ -810,11 +815,13 @@ void QCoeFepInputContext::resetSplitViewWidget(bool keepInputWidget)
     if (!alwaysResize) {
         if (gv->scene() && S60->partial_keyboardAutoTranslation) {
             if (gv->scene()->focusItem()) {
+                QGraphicsItem *focusItem =
+                    m_splitViewPreviousFocusItem ? m_splitViewPreviousFocusItem : gv->scene()->focusItem();
                 // Check if the widget contains cursorPositionChanged signal and disconnect from it.
                 QByteArray signal = QMetaObject::normalizedSignature(SIGNAL(cursorPositionChanged()));
-                int index = gv->scene()->focusItem()->toGraphicsObject()->metaObject()->indexOfSignal(signal.right(signal.length() - 1));
+                int index = focusItem->toGraphicsObject()->metaObject()->indexOfSignal(signal.right(signal.length() - 1));
                 if (index != -1)
-                    disconnect(gv->scene()->focusItem()->toGraphicsObject(), SIGNAL(cursorPositionChanged()), this, SLOT(translateInputWidget()));
+                    disconnect(focusItem->toGraphicsObject(), SIGNAL(cursorPositionChanged()), this, SLOT(translateInputWidget()));
             }
 
             QGraphicsItem *rootItem = 0;
@@ -882,6 +889,11 @@ bool QCoeFepInputContext::isPartialKeyboardSupported()
     return (S60->partial_keyboard || !QApplication::testAttribute(Qt::AA_S60DisablePartialScreenInputMode));
 }
 
+void QCoeFepInputContext::ensureWidgetVisibility()
+{
+    ensureFocusWidgetVisible(S60->splitViewLastWidget);
+}
+
 // Ensure that the input widget is visible in the splitview rect.
 
 void QCoeFepInputContext::ensureFocusWidgetVisible(QWidget *widget)
@@ -913,17 +925,22 @@ void QCoeFepInputContext::ensureFocusWidgetVisible(QWidget *widget)
     // states getting changed.
 
     if (!moveWithinVisibleArea) {
-        // Check if the widget contains cursorPositionChanged signal and connect to it.
-        QByteArray signal = QMetaObject::normalizedSignature(SIGNAL(cursorPositionChanged()));
-        if (gv->scene() && gv->scene()->focusItem() && S60->partial_keyboardAutoTranslation) {
-            int index = gv->scene()->focusItem()->toGraphicsObject()->metaObject()->indexOfSignal(signal.right(signal.length() - 1));
-            if (index != -1)
-                connect(gv->scene()->focusItem()->toGraphicsObject(), SIGNAL(cursorPositionChanged()), this, SLOT(translateInputWidget()));
-        }
         S60->splitViewLastWidget = widget;
         m_splitViewPreviousWindowStates = windowToMove->windowState();
     }
 
+    // Check if the widget contains cursorPositionChanged signal and connect to it.
+    if (gv->scene() && gv->scene()->focusItem() && S60->partial_keyboardAutoTranslation) {
+        QByteArray signal = QMetaObject::normalizedSignature(SIGNAL(cursorPositionChanged()));
+        if (m_splitViewPreviousFocusItem && m_splitViewPreviousFocusItem != gv->scene()->focusItem())
+            disconnect(m_splitViewPreviousFocusItem->toGraphicsObject(), SIGNAL(cursorPositionChanged()), this, SLOT(translateInputWidget()));
+        int index = gv->scene()->focusItem()->toGraphicsObject()->metaObject()->indexOfSignal(signal.right(signal.length() - 1));
+        if (index != -1) {
+            connect(gv->scene()->focusItem()->toGraphicsObject(), SIGNAL(cursorPositionChanged()), this, SLOT(translateInputWidget()));
+            m_splitViewPreviousFocusItem = gv->scene()->focusItem();
+        }
+    }
+
     int windowTop = widget->window()->pos().y();
 
     const bool userResize = widget->testAttribute(Qt::WA_Resized);
@@ -1266,10 +1283,15 @@ void QCoeFepInputContext::translateInputWidget()
 
     m_transformation = (rootItem->transform().isTranslating()) ? QRectF(0,0, gv->width(), rootItem->transform().dy()) : QRectF();
 
-    // Adjust cursor bounding rect to be lower, so that view translates if the cursor gets near
-    // the splitview border.
-    QRect cursorRect = cursorP.boundingRect().adjusted(0, cursor.height(), 0, cursor.height());
-    if (splitViewRect.contains(cursorRect))
+    // Adjust cursor bounding rect towards navigation direction,
+    // so that view translates if the cursor gets near the splitview border.
+    QRect cursorRect = (cursorP.boundingRect().top() < 0) ?
+        cursorP.boundingRect().adjusted(0, -cursor.height(), 0, -cursor.height()) :
+        cursorP.boundingRect().adjusted(0, cursor.height(), 0, cursor.height());
+
+    // If the current cursor position and upcoming cursor positions are visible in the splitview
+    // area, do not move the view.
+    if (splitViewRect.contains(cursorRect) && splitViewRect.contains(cursorP.boundingRect()))
         return;
 
     // New Y position should be ideally just above the keyboard.
@@ -1281,22 +1303,29 @@ void QCoeFepInputContext::translateInputWidget()
     const qreal itemHeight = path.boundingRect().height();
 
     // Limit the maximum translation so that underlaying window content is not exposed.
-    qreal maxY = gv->sceneRect().bottom() - splitViewRect.bottom();
-    maxY = m_transformation.height() ? (qMin(itemHeight, maxY) + m_transformation.height()) : maxY;
-    if (maxY < 0)
-        maxY = 0;
+    qreal availableSpace = gv->sceneRect().bottom() - splitViewRect.bottom();
+    availableSpace = m_transformation.height() ?
+        (qMin(itemHeight, availableSpace) + m_transformation.height()) :
+        availableSpace;
 
     // Translation should happen row-by-row, but initially it needs to ensure that cursor is visible.
     const qreal translation = m_transformation.height() ?
         cursor.height() : (cursorRect.bottom() - vkbRect.top());
-    qreal dy = -(qMin(maxY, translation));
+    qreal dy = 0.0;
+    if (availableSpace > 0)
+        dy = -(qMin(availableSpace, translation));
+    else
+        dy = -(translation);
 
-    // Correct the translation direction, if the cursor rect would be moved outside of application area.
-    if ((cursorRect.bottom() + dy) < 0)
+    // Correct the translation direction, if the cursor rect would be moved above application area.
+    if ((cursorP.boundingRect().bottom() + dy) < 0)
         dy *= -1;
 
-    // Do not allow transform above screen top, nor beyond scenerect
-    if (m_transformation.height() + dy > 0 || gv->sceneRect().bottom() + m_transformation.height() < 0) {
+    // Do not allow transform above screen top, nor beyond scenerect. Also, if there is no available
+    // space anymore, skip translation.
+    if ((m_transformation.height() + dy) > 0
+        || (gv->sceneRect().bottom() + m_transformation.height()) < 0
+        || !availableSpace) {
         // If we already have some transformation, remove it.
         if (m_transformation.height() < 0 || gv->sceneRect().bottom() + m_transformation.height() < 0) {
             rootItem->resetTransform();