Adding support for Smart GO NEXT feature in Android Chrome

Source/web/WebViewImpl.cpp

 /*
  * Copyright (C) 2011, 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 98 matching lines @@
 #include "platform/graphics/Color.h"
 #include "platform/graphics/FirstPaintInvalidationTracking.h"
 #include "platform/graphics/Image.h"
 #include "platform/graphics/ImageBuffer.h"
 #include "platform/scroll/ScrollbarTheme.h"
 #include "platform/weborigin/SchemeRegistry.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebCompositeAndReadbackAsyncCallback.h"
 #include "public/platform/WebDragData.h"
 #include "public/platform/WebFloatPoint.h"
+#include "public/platform/WebFocusType.h"
 #include "public/platform/WebGestureCurve.h"
 #include "public/platform/WebImage.h"
 #include "public/platform/WebLayerTreeView.h"
 #include "public/platform/WebURLRequest.h"
 #include "public/platform/WebVector.h"
 #include "public/web/WebAXObject.h"
 #include "public/web/WebActiveWheelFlingParameters.h"
 #include "public/web/WebAutofillClient.h"
 #include "public/web/WebBeginFrameArgs.h"
 #include "public/web/WebFrameClient.h"
@@ skipping 2383 matching lines @@
                 flags |= WebTextInputFlagAutocapitalizeCharacters;
             else if (autocapitalize == words)
                 flags |= WebTextInputFlagAutocapitalizeWords;
             else if (autocapitalize == sentences)
                 flags |= WebTextInputFlagAutocapitalizeSentences;
             else
                 ASSERT_NOT_REACHED();
         }
     }
 
+    if (isListeningToKeyboardEvents(*element))
+        flags |= WebTextInputFlagListeningToKeyboardEvents;
+
+    if (nextFocusableElement(element, WebFocusTypeForward))
+        flags |= WebTextInputFlagHaveNextFocusableElement;
+
+    if (nextFocusableElement(element, WebFocusTypeBackward))
+        flags |= WebTextInputFlagHavePreviousFocusableElement;
+
     return flags;
 }
 
+Element* WebViewImpl::nextFocusableElement(Element* element, WebFocusType focusType)
+{
+    if (!element->isFormControlElement() && !element->isContentEditable())
+        return nullptr;
+
+    HTMLFormElement* formOwner = nullptr;
+    if (element->isContentEditable()) {
+        // Check whether it's child of a form element
+        Element* parent = element;

[tkent, 2015/04/20 01:40:20]

formOwner = Traversal<HTMLFormElement>::firstAncestor(*element);

[AKV, 2015/04/20 19:46:49]

Done. Thanks., this is very simple :)

+        while ((parent = parent->parentElement())) {
+            if (!isHTMLFormElement(parent))
+                continue;
+            formOwner = reinterpret_cast<HTMLFormElement*>(toHTMLElement(parent));

[tkent, 2015/04/20 01:40:20]

Do not use reinterpret_cast<>.

[AKV, 2015/04/20 19:46:49]

Done.

+            break;
+        }
+    } else {
+        HTMLFormControlElement* formControlElement = toHTMLFormControlElement(element);

[tkent, 2015/04/20 01:40:21]

formOwner = toHTMLFormControlElement(element)->formOwner();

[AKV, 2015/04/20 19:46:49]

Done.

+        formOwner = formControlElement->formOwner();
+    }
+
+    if (!formOwner)
+        return nullptr;
+
+    Node* nextNode = element;
+    while ((nextNode = page()->focusController().findFocusableNode(focusType, *nextNode))) {
+        if (nextNode->isContentEditable() && nextNode->isDescendantOf(reinterpret_cast<Node*>(formOwner)))

[tkent, 2015/04/20 01:40:21]

Do not use reinterpret_cast<>.

[AKV, 2015/04/20 19:46:49]

Done.

+            return toElement(nextNode);
+        if (!toElement(nextNode)->isFormControlElement())
+            continue;
+        HTMLFormControlElement* formElement = toHTMLFormControlElement(nextNode);
+        if (formElement->formOwner() != formOwner)
+            continue;
+        LayoutObject* layout = nextNode->layoutObject();
+        if (layout && layout->isTextControl()) {
+            // TODO(AKV) Extend it for Select element, Radio button and Check boxes

[tkent, 2015/04/20 01:40:21]

Please use the username part of your @chromium.org address in TODO().

[AKV, 2015/04/20 19:46:49]

Done.

+            return toElement(nextNode);
+        }
+    }
+    return nullptr;
+}
+
+bool WebViewImpl::isListeningToKeyboardEvents(const Element& element)
+{
+    if (!element.isFormControlElement())

[tkent, 2015/04/20 01:40:21]

This returns a wrong result for  contenteditable elements with keyboard event
listeners.

[AKV, 2015/04/20 19:46:49]

Thanks. I corrected :)

+        return false;
+
+    return (element.hasEventListeners(EventTypeNames::keydown) || element.hasEventListeners(EventTypeNames::keypress) || element.hasEventListeners(EventTypeNames::keyup));

[tkent, 2015/04/20 01:40:20]

I found this didn't work for the following case.

<body onkeypress="handleKeys(event)">
<form action=...>
<input name=query>
</form>
</body>

[AKV, 2015/04/20 19:46:49]

Thanks. I just corrected using document listener and parent listeners. Please
let me know can we achieve this in a better way than this.

+}
+
+void WebViewImpl::advanceFocusToNextFormControl(WebFocusType focusType)

[tkent, 2015/04/20 01:40:21]

You clarified you'd like to handle contenteditable elements.  So, this should be
advanceForusToNextFocusableElement().  It's consistent with
nextFocusableElement().

However, now I feel these names are too general.  I think advanceFocusInForm and
nextFocusableElementInForm are better.

[AKV, 2015/04/20 19:46:49]

Done. Thanks

+{
+    Element* element = focusedElement();
+    if (!element)
+        return;
+
+    Element* nextElement = nextFocusableElement(element, focusType);

[tkent, 2015/04/20 01:40:21]

You can make |nextElement| RefPtrWillBeRawPtr<Element>, and remove
|nextFocusElement|.

[AKV, 2015/04/20 19:46:49]

Done.

+    if (!nextElement)
+        return;
+
+    RefPtrWillBeRawPtr<Element> nextFocusElement = nextElement;
+    nextFocusElement->scrollIntoViewIfNeeded(true /*centerIfNeeded*/);
+    nextFocusElement->focus(false, focusType);
+}
+
 WebString WebViewImpl::inputModeOfFocusedElement()
 {
     if (!RuntimeEnabledFeatures::inputModeAttributeEnabled())
         return WebString();
 
     Element* element = focusedElement();
     if (!element)
         return WebString();
 
     if (isHTMLInputElement(*element)) {
@@ skipping 1977 matching lines @@
     return mainFrameImpl()->frameView()->layoutSize().width() == m_size.width
         || (constraints.minimumScale == constraints.maximumScale && constraints.minimumScale != -1);
 }
 
 void WebViewImpl::forceNextWebGLContextCreationToFail()
 {
     WebGLRenderingContext::forceNextWebGLContextCreationToFail();
 }
 
 } // namespace blink