Implement select listbox using shadow DOM

Source/core/html/HTMLSelectElement.cpp

Index: Source/core/html/HTMLSelectElement.cpp
diff --git a/Source/core/html/HTMLSelectElement.cpp b/Source/core/html/HTMLSelectElement.cpp
index 3b7744d2667d8d9a983bc53df0ad8de19c479a83..8141ef9ccbb460400d5b84a34448ec06de525d79 100644
--- a/Source/core/html/HTMLSelectElement.cpp
+++ b/Source/core/html/HTMLSelectElement.cpp
@@ -39,16 +39,23 @@
 #include "core/events/GestureEvent.h"
 #include "core/events/KeyboardEvent.h"
 #include "core/events/MouseEvent.h"
+#include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
 #include "core/html/FormDataList.h"
 #include "core/html/HTMLFormElement.h"
+#include "core/html/HTMLOptGroupElement.h"
 #include "core/html/HTMLOptionElement.h"
 #include "core/html/forms/FormController.h"
+#include "core/page/AutoscrollController.h"
 #include "core/page/EventHandler.h"
+#include "core/page/Page.h"
 #include "core/page/SpatialNavigation.h"
+#include "core/rendering/HitTestRequest.h"
+#include "core/rendering/HitTestResult.h"
 #include "core/rendering/RenderListBox.h"
 #include "core/rendering/RenderMenuList.h"
 #include "core/rendering/RenderTheme.h"
+#include "core/rendering/RenderView.h"
 #include "platform/PlatformMouseEvent.h"
 #include "platform/text/PlatformLocale.h"
 
@@ -80,12 +87,16 @@ HTMLSelectElement::HTMLSelectElement(Document& document, HTMLFormElement* form)
 
 PassRefPtrWillBeRawPtr<HTMLSelectElement> HTMLSelectElement::create(Document& document)
 {
-    return adoptRefWillBeNoop(new HTMLSelectElement(document, 0));
+    RefPtrWillBeRawPtr<HTMLSelectElement> select = adoptRefWillBeNoop(new HTMLSelectElement(document, 0));
+    select->ensureUserAgentShadowRoot();
+    return select.release();
 }
 
 PassRefPtrWillBeRawPtr<HTMLSelectElement> HTMLSelectElement::create(Document& document, HTMLFormElement* form)
 {
-    return adoptRefWillBeNoop(new HTMLSelectElement(document, form));
+    RefPtrWillBeRawPtr<HTMLSelectElement> select = adoptRefWillBeNoop(new HTMLSelectElement(document, form));
+    select->ensureUserAgentShadowRoot();
+    return select.release();
 }
 
 const AtomicString& HTMLSelectElement::formControlType() const
@@ -334,7 +345,7 @@ void HTMLSelectElement::parseAttribute(const QualifiedName& name, const AtomicSt
 
         m_size = size;
         setNeedsValidityCheck();
-        if (m_size != oldSize && inActiveDocument()) {
+        if (m_size != oldSize && document().isActive() && inDocument()) {

[tkent, 2014/07/08 04:43:46]

This change looks unnecessary.

[keishi, 2014/07/10 09:48:03]

Done.

             lazyReattachIfAttached();
             setRecalcListItems();
         }
@@ -366,7 +377,7 @@ bool HTMLSelectElement::canSelectAll() const
     return !usesMenuList();
 }
 
-RenderObject* HTMLSelectElement::createRenderer(RenderStyle*)
+RenderObject* HTMLSelectElement::createRenderer(RenderStyle* style)

[tkent, 2014/07/08 02:20:59]

This change looks unnecessary.

[keishi, 2014/07/10 09:48:03]

Done.

 {
     if (usesMenuList())
         return new RenderMenuList(this);
@@ -396,7 +407,6 @@ void HTMLSelectElement::childrenChanged(const ChildrenChange& change)
 {
     setRecalcListItems();
     setNeedsValidityCheck();
-    m_lastOnChangeSelection.clear();

[tkent, 2014/07/08 04:43:46]

Why do you remove this?

[keishi, 2014/07/10 09:48:03]

Reverted. See comment for HTMLSelectElement::listBoxOnChange.

 
     HTMLFormControlElementWithState::childrenChanged(change);
 }
@@ -523,8 +533,15 @@ int HTMLSelectElement::nextValidIndex(int listIndex, SkipDirection direction, in
     for (listIndex += direction; listIndex >= 0 && listIndex < size; listIndex += direction) {
         --skip;
         HTMLElement* element = listItems[listIndex];
-        if (!isHTMLOptionElement(*element) || toHTMLOptionElement(element)->isDisabledFormControl() || toHTMLOptionElement(element)->isDisplayNone())
+        if (isHTMLOptionElement(*element)) {
+            const HTMLOptionElement& option = toHTMLOptionElement(*element);

[tkent, 2014/07/08 04:43:46]

This cast is unnecessary. isDisabledFormControl and renderer() are available in
Element.

[keishi, 2014/07/10 09:48:03]

Done.

+            if (option.isDisabledFormControl())
+                continue;
+            if (!usesMenuList() && !option.renderer())
+                continue;
+        } else {
             continue;

[tkent, 2014/07/08 04:43:46]

We prefer early continue.

if (!isHTMLOptionElement(*element))
    continue;

[keishi, 2014/07/10 09:48:03]

Done.

+        }
         lastGoodIndex = listIndex;
         if (skip <= 0)
             break;
@@ -626,7 +643,10 @@ void HTMLSelectElement::setActiveSelectionAnchorIndex(int index)
 
 void HTMLSelectElement::setActiveSelectionEndIndex(int index)
 {
+    if (index == m_activeSelectionEndIndex)
+        return;
     m_activeSelectionEndIndex = index;
+    setNeedsStyleRecalc(SubtreeStyleChange);
 }
 
 void HTMLSelectElement::updateListBoxSelection(bool deselectOtherOptions)
@@ -640,7 +660,7 @@ void HTMLSelectElement::updateListBoxSelection(bool deselectOtherOptions)
     const WillBeHeapVector<RawPtrWillBeMember<HTMLElement> >& items = listItems();
     for (unsigned i = 0; i < items.size(); ++i) {
         HTMLElement* element = items[i];
-        if (!isHTMLOptionElement(*element) || toHTMLOptionElement(element)->isDisabledFormControl() || toHTMLOptionElement(element)->isDisplayNone())
+        if (!isHTMLOptionElement(*element) || toHTMLOptionElement(element)->isDisabledFormControl() || !toHTMLOptionElement(element)->renderer())
             continue;
 
         if (i >= start && i <= end)
@@ -651,8 +671,8 @@ void HTMLSelectElement::updateListBoxSelection(bool deselectOtherOptions)
             toHTMLOptionElement(element)->setSelectedState(m_cachedStateForActiveSelection[i]);
     }
 
-    scrollToSelection();
     setNeedsValidityCheck();
+    scrollToSelection();
     notifyFormStateChanged();
 }
 
@@ -662,25 +682,24 @@ void HTMLSelectElement::listBoxOnChange()
 
     const WillBeHeapVector<RawPtrWillBeMember<HTMLElement> >& items = listItems();
 
-    // If the cached selection list is empty, or the size has changed, then fire
-    // dispatchFormControlChangeEvent, and return early.
-    // FIXME: Why? This looks unreasonable.
-    if (m_lastOnChangeSelection.isEmpty() || m_lastOnChangeSelection.size() != items.size()) {
-        dispatchFormControlChangeEvent();
-        return;
-    }
-
     // Update m_lastOnChangeSelection and fire dispatchFormControlChangeEvent.
     bool fireOnChange = false;
     for (unsigned i = 0; i < items.size(); ++i) {
         HTMLElement* element = items[i];
         bool selected = isHTMLOptionElement(*element) && toHTMLOptionElement(element)->selected();
-        if (selected != m_lastOnChangeSelection[i])
+        if (i < m_lastOnChangeSelection.size()) {
+            if (selected != m_lastOnChangeSelection[i]) {
+                fireOnChange = true;
+                break;
+            }
+        } else if (selected) {
             fireOnChange = true;
-        m_lastOnChangeSelection[i] = selected;
+            break;
+        }
     }
 
     if (fireOnChange) {
+        saveLastSelection();
         RefPtrWillBeRawPtr<HTMLSelectElement> protector(this);
         dispatchInputEvent();
         dispatchFormControlChangeEvent();
@@ -703,11 +722,13 @@ void HTMLSelectElement::dispatchInputAndChangeEventForMenuList(bool requiresUser
 
 void HTMLSelectElement::scrollToSelection()
 {
+    if (!isFinishedParsingChildren())
+        return;
     if (usesMenuList())
         return;
-
-    if (RenderObject* renderer = this->renderer())
-        toRenderListBox(renderer)->selectionChanged();
+    scrollTo(activeSelectionEndListIndex());
+    if (AXObjectCache* cache = document().existingAXObjectCache())
+        cache->selectedChildrenChanged(this);
 }
 
 void HTMLSelectElement::setOptionsChangedOnRenderer()
@@ -715,8 +736,6 @@ void HTMLSelectElement::setOptionsChangedOnRenderer()
     if (RenderObject* renderer = this->renderer()) {
         if (usesMenuList())
             toRenderMenuList(renderer)->setOptionsChanged(true);
-        else
-            toRenderListBox(renderer)->setOptionsChanged(true);
     }
 }
 
@@ -858,11 +877,21 @@ void HTMLSelectElement::setSuggestedIndex(int suggestedIndex)
 
     if (RenderObject* renderer = this->renderer())  {
         renderer->updateFromElement();
-        if (renderer->isListBox())
-            toRenderListBox(renderer)->scrollToRevealElementAtListIndex(suggestedIndex);
+        scrollTo(suggestedIndex);
     }
 }
 
+void HTMLSelectElement::scrollTo(int listIndex)
+{
+    if (listIndex < 0)
+        return;
+    const WillBeHeapVector<RawPtrWillBeMember<HTMLElement> >& items = listItems();
+    int listSize = static_cast<int>(items.size());
+    if (listIndex >= listSize)
+        return;
+    items[listIndex]->scrollIntoViewIfNeeded(false);
+}
+
 void HTMLSelectElement::optionSelectionStateChanged(HTMLOptionElement* option, bool optionIsSelected)
 {
     ASSERT(option->ownerSelectElement() == this);
@@ -874,6 +903,17 @@ void HTMLSelectElement::optionSelectionStateChanged(HTMLOptionElement* option, b
         selectOption(nextSelectableListIndex(-1));
 }
 
+void HTMLSelectElement::optionRemoved(HTMLOptionElement* option)

[tkent, 2014/07/08 04:43:46]

probably the argument type should be |const HTMLOptionElement&|.

[keishi, 2014/07/10 09:48:03]

Done.

[keishi, 2014/07/10 09:48:03]

Done.

+{
+    if (m_activeSelectionAnchorIndex < 0 && m_activeSelectionEndIndex < 0)
+        return;
+    int listIndex = optionToListIndex(option->index());
+    if (listIndex <= m_activeSelectionAnchorIndex)
+        m_activeSelectionAnchorIndex--;
+    if (listIndex <= m_activeSelectionEndIndex)
+        m_activeSelectionEndIndex--;
+}
+
 void HTMLSelectElement::selectOption(int optionIndex, SelectOptionFlags flags)
 {
     bool shouldDeselect = !m_multiple || (flags & DeselectOtherOptions);
@@ -909,10 +949,12 @@ void HTMLSelectElement::selectOption(int optionIndex, SelectOptionFlags flags)
         if (flags & DispatchInputAndChangeEvent)
             dispatchInputAndChangeEventForMenuList();
         if (RenderObject* renderer = this->renderer()) {
-            if (usesMenuList())
+            if (usesMenuList()) {
                 toRenderMenuList(renderer)->didSetSelectedIndex(listIndex);
-            else if (renderer->isListBox())
-                toRenderListBox(renderer)->selectionChanged();
+            } else if (renderer->isListBox()) {
+                if (AXObjectCache* cache = document().existingAXObjectCache())
+                    cache->selectedChildrenChanged(this);
+            }
         }
     }
 
@@ -1053,11 +1095,10 @@ void HTMLSelectElement::restoreFormControlState(const FormControlState& state)
 
 void HTMLSelectElement::parseMultipleAttribute(const AtomicString& value)
 {
-    bool oldUsesMenuList = usesMenuList();
     m_multiple = !value.isNull();
     setNeedsValidityCheck();
-    if (oldUsesMenuList != usesMenuList())
-        lazyReattachIfAttached();
+
+    lazyReattachIfAttached();
 }
 
 bool HTMLSelectElement::appendFormData(FormDataList& list, bool)
@@ -1335,6 +1376,32 @@ void HTMLSelectElement::updateSelectedState(int listIndex, bool multi, bool shif
     updateListBoxSelection(!multiSelect);
 }
 
+int HTMLSelectElement::listIndexForEventTargetOption(const Event& event)
+{
+    Node* targetNode = event.target()->toNode();
+    if (!targetNode || !isHTMLOptionElement(*targetNode))
+        return -1;
+    return listIndexForOption(toHTMLOptionElement(*targetNode));
+}
+
+int HTMLSelectElement::listIndexForOption(const HTMLOptionElement& option)
+{
+    const WillBeHeapVector<RawPtrWillBeMember<HTMLElement> >& items = this->listItems();
+    size_t length = items.size();
+    for (size_t i = 0; i < length; ++i) {
+        if (items[i] == &option)
+            return i;
+    }
+    return -1;
+}
+
+AutoscrollController* HTMLSelectElement::autoscrollController() const
+{
+    if (Page* page = document().page())
+        return &page->autoscrollController();
+    return 0;
+}
+
 void HTMLSelectElement::listBoxDefaultEventHandler(Event* event)
 {
     const WillBeHeapVector<RawPtrWillBeMember<HTMLElement> >& listItems = this->listItems();
@@ -1346,8 +1413,7 @@ void HTMLSelectElement::listBoxDefaultEventHandler(Event* event)
 
         // Convert to coords relative to the list box if needed.
         GestureEvent& gestureEvent = toGestureEvent(*event);
-        IntPoint localOffset = roundedIntPoint(renderer()->absoluteToLocal(gestureEvent.absoluteLocation(), UseTransforms));
-        int listIndex = toRenderListBox(renderer())->listIndexAtOffset(toIntSize(localOffset));
+        int listIndex = listIndexForEventTargetOption(gestureEvent);
         if (listIndex >= 0) {
             if (!isDisabledFormControl())
                 updateSelectedState(listIndex, true, gestureEvent.shiftKey());
@@ -1359,10 +1425,12 @@ void HTMLSelectElement::listBoxDefaultEventHandler(Event* event)
         if (!renderer() || !renderer()->isListBox() || isDisabledFormControl())
             return;
 
+        if (Page* page = document().page())
+            page->autoscrollController().startAutoscrollForSelection(renderer());
+
         // Convert to coords relative to the list box if needed.
         MouseEvent* mouseEvent = toMouseEvent(event);
-        IntPoint localOffset = roundedIntPoint(renderer()->absoluteToLocal(mouseEvent->absoluteLocation(), UseTransforms));
-        int listIndex = toRenderListBox(renderer())->listIndexAtOffset(toIntSize(localOffset));
+        int listIndex = listIndexForEventTargetOption(*mouseEvent);
         if (listIndex >= 0) {
             if (!isDisabledFormControl()) {
 #if OS(MACOSX)
@@ -1376,13 +1444,11 @@ void HTMLSelectElement::listBoxDefaultEventHandler(Event* event)
 
             event->setDefaultHandled();
         }
-    } else if (event->type() == EventTypeNames::mousemove && event->isMouseEvent() && !toRenderBox(renderer())->canBeScrolledAndHasScrollableArea()) {
+    } else if (event->type() == EventTypeNames::mousemove && event->isMouseEvent()) {
         MouseEvent* mouseEvent = toMouseEvent(event);
         if (mouseEvent->button() != LeftButton || !mouseEvent->buttonDown())
             return;
-
-        IntPoint localOffset = roundedIntPoint(renderer()->absoluteToLocal(mouseEvent->absoluteLocation(), UseTransforms));
-        int listIndex = toRenderListBox(renderer())->listIndexAtOffset(toIntSize(localOffset));
+        int listIndex = listIndexForEventTargetOption(*mouseEvent);
         if (listIndex >= 0) {
             if (!isDisabledFormControl()) {
                 if (m_multiple) {
@@ -1399,7 +1465,7 @@ void HTMLSelectElement::listBoxDefaultEventHandler(Event* event)
                 }
             }
         }
-    } else if (event->type() == EventTypeNames::mouseup && event->isMouseEvent() && toMouseEvent(event)->button() == LeftButton && renderer() && !toRenderBox(renderer())->autoscrollInProgress()) {

[tkent, 2014/07/08 04:43:46]

Is it safe to remove autoscrollInProgress check?

[keishi, 2014/07/10 09:48:03]

I added back this check and added a call to stopAutoscroll so it balances the
call to startAutoscrollForSelection I added above.

+    } else if (event->type() == EventTypeNames::mouseup && event->isMouseEvent() && toMouseEvent(event)->button() == LeftButton && renderer()) {
         // We didn't start this click/drag on any options.
         if (m_lastOnChangeSelection.isEmpty())
             return;
@@ -1478,7 +1544,7 @@ void HTMLSelectElement::listBoxDefaultEventHandler(Event* event)
                 setActiveSelectionAnchorIndex(m_activeSelectionEndIndex);
             }
 
-            toRenderListBox(renderer())->scrollToRevealElementAtListIndex(endIndex);
+            scrollTo(endIndex);
             if (selectNewItem) {
                 updateListBoxSelection(deselectOthers);
                 listBoxOnChange();
@@ -1629,6 +1695,7 @@ void HTMLSelectElement::finishParsingChildren()
 {
     HTMLFormControlElementWithState::finishParsingChildren();
     updateListItemSelectedStates();
+    scrollToSelection();
 }
 
 bool HTMLSelectElement::anonymousIndexedSetter(unsigned index, PassRefPtrWillBeRawPtr<HTMLOptionElement> value, ExceptionState& exceptionState)
@@ -1664,4 +1731,24 @@ void HTMLSelectElement::trace(Visitor* visitor)
     HTMLFormControlElementWithState::trace(visitor);
 }
 
+void HTMLSelectElement::didAddUserAgentShadowRoot(ShadowRoot& root)
+{
+    RefPtrWillBeRawPtr<HTMLContentElement> content = HTMLContentElement::create(document());
+    content->setAttribute(selectAttr, "option,optgroup");
+    root.appendChild(content);
+}
+
+HTMLOptionElement* HTMLSelectElement::spatialNavigationFocusedOption()
+{
+    if (!isSpatialNavigationEnabled(document().frame()))
+        return nullptr;
+    int focusedIndex = activeSelectionEndListIndex();
+    if (focusedIndex < 0)
+        focusedIndex = firstSelectableListIndex();
+    if (focusedIndex < 0)
+        return nullptr;
+    HTMLElement* focused = listItems()[focusedIndex];
+    return isHTMLOptionElement(focused) ? toHTMLOptionElement(focused) : nullptr;
+}
+
 } // namespace