Spatial navigation enhancements

Source/core/html/HTMLElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2011 Motorola Mobility. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 20 matching lines @@
 #include "XMLNames.h"
 #include "bindings/v8/ScriptController.h"
 #include "bindings/v8/ScriptEventListener.h"
 #include "core/css/CSSParser.h"
 #include "core/css/CSSValuePool.h"
 #include "core/css/StylePropertySet.h"
 #include "core/dom/DocumentFragment.h"
 #include "core/dom/EventListener.h"
 #include "core/dom/EventNames.h"
 #include "core/dom/ExceptionCode.h"
+#include "core/dom/KeyboardEvent.h"
 #include "core/dom/NodeTraversal.h"
 #include "core/dom/Text.h"
 #include "core/editing/markup.h"
 #include "core/html/HTMLBRElement.h"
 #include "core/html/HTMLFormElement.h"
 #include "core/html/HTMLTemplateElement.h"
 #include "core/html/HTMLTextFormControlElement.h"
 #include "core/html/parser/HTMLParserIdioms.h"
 #include "core/loader/FrameLoader.h"
 #include "core/page/Frame.h"
+#include "core/page/Settings.h"
 #include "core/rendering/RenderWordBreak.h"
 #include <wtf/StdLibExtras.h>
 #include <wtf/text/CString.h>
 
 namespace WebCore {
 
 using namespace HTMLNames;
 using namespace WTF;
 
 using std::min;
@@ skipping 530 matching lines @@
 
     if (verticalAlignValue != CSSValueInvalid)
         addPropertyToPresentationAttributeStyle(style, CSSPropertyVerticalAlign, verticalAlignValue);
 }
 
 bool HTMLElement::hasCustomFocusLogic() const
 {
     return false;
 }
 
+bool HTMLElement::supportsSpatialNavigationFocus() const
+{
+    // This function checks whether the element satisfies the extended criteria
+    // for the element to be focusable, introduced by spatial navigation feature,
+    // i.e. checks if click or keyboard event handler is specified.
+    // This is the way to make it possible to navigate to (focus) elements
+    // which web designer meant for being active (made them respond to click events).
+
+    if (!document()->settings() || !document()->settings()->spatialNavigationEnabled())
+        return false;
+    EventTarget* target = const_cast<HTMLElement*>(this);
+    return target->hasEventListeners(eventNames().clickEvent)
+        || target->hasEventListeners(eventNames().keydownEvent)
+        || target->hasEventListeners(eventNames().keypressEvent)
+        || target->hasEventListeners(eventNames().keyupEvent);
+}
+
 bool HTMLElement::supportsFocus() const
 {
     // FIXME: supportsFocus() can be called when layout is not up to date.
     // Logic that deals with the renderer should be moved to rendererIsFocusable().
     // But supportsFocus must return true when the element is editable, or else
     // it won't be focusable. Furthermore, supportsFocus cannot just return true
     // always or else tabIndex() will change for all HTML elements.
-    return Element::supportsFocus() || (rendererIsEditable() && parentNode() && !parentNode()->rendererIsEditable());
+    return Element::supportsFocus() || (rendererIsEditable() && parentNode() && !parentNode()->rendererIsEditable())
+        || supportsSpatialNavigationFocus();
 }
 
 String HTMLElement::contentEditable() const
 {
     const AtomicString& value = fastGetAttribute(contenteditableAttr);
 
     if (value.isNull())
         return "inherit";
     if (value.isEmpty() || equalIgnoringCase(value, "true"))
         return "true";
@@ skipping 403 matching lines @@
         return;
 
     // If the string is a named CSS color or a 3/6-digit hex color, use that.
     Color parsedColor(colorString);
     if (!parsedColor.isValid())
         parsedColor.setRGB(parseColorStringWithCrazyLegacyRules(colorString));
 
     style->setProperty(propertyID, cssValuePool().createColorValue(parsedColor.rgb()));
 }
 
+void HTMLElement::defaultEventHandler(Event* event)
+{
+    if (event->type() == eventNames().keypressEvent && event->isKeyboardEvent()) {
+        handleKeypressEvent(toKeyboardEvent(event));
+        if (event->defaultHandled())
+            return;
+    }
+
+    StyledElement::defaultEventHandler(event);
+}
+
+void HTMLElement::handleKeypressEvent(KeyboardEvent* event)
+{
+    if (!document()->settings() || !document()->settings()->spatialNavigationEnabled() || !supportsFocus())
+        return;
+    int charCode = event->charCode();
+    if (charCode == '\r' || charCode == ' ') {
+        dispatchSimulatedClick(event);
+        event->setDefaultHandled();
+    }
+}
+
 } // namespace WebCore
 
 #ifndef NDEBUG
 
 // For use in the debugger
 void dumpInnerHTML(WebCore::HTMLElement*);
 
 void dumpInnerHTML(WebCore::HTMLElement* element)
 {
     printf("%s\n", element->innerHTML().ascii().data());
 }
 #endif