Index: Source/core/html/HTMLImageFallbackHelper.cpp |
diff --git a/Source/core/html/HTMLImageFallbackHelper.cpp b/Source/core/html/HTMLImageFallbackHelper.cpp |
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+// Copyright 2014 The Chromium Authors. All rights reserved. |
+// Use of this source code is governed by a BSD-style license that can be |
+// found in the LICENSE file. |
+ |
+#include "config.h" |
+#include "core/html/HTMLImageFallbackHelper.h" |
+ |
+#include "core/HTMLNames.h" |
+#include "core/InputTypeNames.h" |
+#include "core/dom/ElementRareData.h" |
+#include "core/dom/Text.h" |
+#include "core/dom/shadow/ShadowRoot.h" |
+#include "core/fetch/ImageResource.h" |
+#include "core/html/FormDataList.h" |
+#include "core/html/HTMLDivElement.h" |
+#include "core/html/HTMLElement.h" |
+#include "core/html/HTMLImageElement.h" |
+#include "core/html/HTMLImageLoader.h" |
+#include "core/html/HTMLInputElement.h" |
+#include "core/html/HTMLStyleElement.h" |
+#include "wtf/PassOwnPtr.h" |
+#include "wtf/text/StringBuilder.h" |
+ |
+namespace blink { |
+ |
+using namespace HTMLNames; |
+ |
+static bool noImageSourceSpecified(const Element& element) |
+{ |
+ bool noSrcSpecified = !element.hasAttribute(srcAttr) || element.getAttribute(srcAttr).isNull() || element.getAttribute(srcAttr).isEmpty(); |
+ bool noSrcsetSpecified = !element.hasAttribute(srcsetAttr) || element.getAttribute(srcsetAttr).isNull() || element.getAttribute(srcsetAttr).isEmpty(); |
+ return noSrcSpecified && noSrcsetSpecified; |
+} |
+ |
+void HTMLImageFallbackHelper::createAltTextShadowTree(Element& element) |
+{ |
+ ShadowRoot& root = element.ensureUserAgentShadowRoot(); |
+ |
+ RefPtrWillBeRawPtr<HTMLDivElement> container = HTMLDivElement::create(element.document()); |
+ root.appendChild(container); |
+ container->setAttribute(idAttr, AtomicString("alttext-container", AtomicString::ConstructFromLiteral)); |
+ container->setInlineStyleProperty(CSSPropertyOverflow, CSSValueHidden); |
+ container->setInlineStyleProperty(CSSPropertyBorderWidth, 1, CSSPrimitiveValue::CSS_PX); |
+ container->setInlineStyleProperty(CSSPropertyBorderStyle, CSSValueSolid); |
+ container->setInlineStyleProperty(CSSPropertyBorderColor, CSSValueSilver); |
+ container->setInlineStyleProperty(CSSPropertyDisplay, CSSValueInlineBlock); |
+ container->setInlineStyleProperty(CSSPropertyBoxSizing, CSSValueBorderBox); |
+ container->setInlineStyleProperty(CSSPropertyPadding, 1, CSSPrimitiveValue::CSS_PX); |
+ |
+ RefPtrWillBeRawPtr<HTMLImageElement> brokenImage = HTMLImageElement::create(element.document()); |
+ container->appendChild(brokenImage); |
+ brokenImage->setIsFallbackImage(); |
+ brokenImage->setAttribute(idAttr, AtomicString("alttext-image", AtomicString::ConstructFromLiteral)); |
+ brokenImage->setAttribute(widthAttr, AtomicString("16", AtomicString::ConstructFromLiteral)); |
+ brokenImage->setAttribute(heightAttr, AtomicString("16", AtomicString::ConstructFromLiteral)); |
+ brokenImage->setAttribute(alignAttr, AtomicString("left", AtomicString::ConstructFromLiteral)); |
+ brokenImage->setInlineStyleProperty(CSSPropertyMargin, 0, CSSPrimitiveValue::CSS_PX); |
+ |
+ RefPtrWillBeRawPtr<HTMLDivElement> altText = HTMLDivElement::create(element.document()); |
+ container->appendChild(altText); |
+ altText->setInlineStyleProperty(CSSPropertyOverflow, CSSValueHidden); |
+ altText->setInlineStyleProperty(CSSPropertyDisplay, CSSValueBlock); |
+ |
+ RefPtrWillBeRawPtr<Text> text = Text::create(element.document(), toHTMLElement(element).altText()); |
+ altText->appendChild(text); |
+} |
+ |
+PassRefPtr<RenderStyle> HTMLImageFallbackHelper::customStyleForAltText(Element& element, PassRefPtr<RenderStyle> newStyle) |
+{ |
+ // If we have an author shadow root or have not created the UA shadow root yet, bail early. We can't |
+ // use ensureUserAgentShadowRoot() here because that would alter the DOM tree during style recalc. |
+ if (element.shadowRoot() || !element.userAgentShadowRoot()) |
+ return newStyle; |
+ |
+ Element* placeHolder = element.userAgentShadowRoot()->getElementById("alttext-container"); |
+ Element* brokenImage = element.userAgentShadowRoot()->getElementById("alttext-image"); |
+ |
+ if (element.document().inQuirksMode()) { |
+ // Mimic the behaviour of the image host by setting symmetric dimensions if only one dimension is specified. |
+ if (newStyle->width().isSpecifiedOrIntrinsic() && newStyle->height().isAuto()) |
+ newStyle->setHeight(newStyle->width()); |
+ else if (newStyle->height().isSpecifiedOrIntrinsic() && newStyle->width().isAuto()) |
+ newStyle->setWidth(newStyle->height()); |
+ if (newStyle->width().isSpecifiedOrIntrinsic() && newStyle->height().isSpecifiedOrIntrinsic()) { |
+ placeHolder->setInlineStyleProperty(CSSPropertyVerticalAlign, CSSValueBaseline); |
+ } |
+ } |
+ |
+ // If the image has specified dimensions allow the alt-text container expand to fill them. |
+ if (newStyle->width().isSpecifiedOrIntrinsic() && newStyle->height().isSpecifiedOrIntrinsic()) { |
+ placeHolder->setInlineStyleProperty(CSSPropertyWidth, 100, CSSPrimitiveValue::CSS_PERCENTAGE); |
+ placeHolder->setInlineStyleProperty(CSSPropertyHeight, 100, CSSPrimitiveValue::CSS_PERCENTAGE); |
+ } |
+ |
+ // Make sure the broken image icon appears on the appropriate side of the image for the element's writing direction. |
+ brokenImage->setInlineStyleProperty(CSSPropertyFloat, AtomicString(newStyle->direction() == LTR ? "left" : "right")); |
+ |
+ // This is an <img> with no attributes, so don't display anything. |
+ if (noImageSourceSpecified(element) && !newStyle->width().isSpecifiedOrIntrinsic() && !newStyle->height().isSpecifiedOrIntrinsic() && toHTMLElement(element).altText().isEmpty()) |
+ newStyle->setDisplay(NONE); |
+ |
+ // This preserves legacy behaviour originally defined when alt-text was managed by RenderImage. |
+ if (noImageSourceSpecified(element)) |
+ brokenImage->setInlineStyleProperty(CSSPropertyDisplay, CSSValueNone); |
+ else |
+ brokenImage->setInlineStyleProperty(CSSPropertyDisplay, CSSValueInline); |
+ |
+ return newStyle; |
+} |
+ |
+} // namespace blink |
+ |