third_party/WebKit/Source/core/layout/LayoutTextFragment.h

   1 /*
   2  * (C) 1999 Lars Knoll (knoll@kde.org)
   3  * (C) 2000 Dirk Mueller (mueller@kde.org)
   4  * Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Library General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Library General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Library General Public License
  17  * along with this library; see the file COPYING.LIB.  If not, write to
  18  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  19  * Boston, MA 02110-1301, USA.
  20  *
  21  */
  22
  23 #ifndef LayoutTextFragment_h
  24 #define LayoutTextFragment_h
  25
  26 #include "core/layout/LayoutText.h"
  27
  28 namespace blink {
  29
  30 class FirstLetterPseudoElement;
  31
  32 // Used to represent a text substring of an element, e.g., for text runs that are split because of
  33 // first letter and that must therefore have different styles (and positions in the layout tree).
  34 // We cache offsets so that text transformations can be applied in such a way that we can recover
  35 // the original unaltered string from our corresponding DOM node.
  36 class LayoutTextFragment final : public LayoutText {
  37 public:
  38     LayoutTextFragment(Node*, StringImpl*, int startOffset, int length);
  39     LayoutTextFragment(Node*, StringImpl*);
  40     ~LayoutTextFragment() override;
  41
  42     bool isTextFragment() const override { return true; }
  43
  44     bool canBeSelectionLeaf() const override { return node() && node()->hasEditableStyle(); }
  45
  46     unsigned start() const { return m_start; }
  47     unsigned end() const { return m_end; }
  48
  49     unsigned textStartOffset() const override { return start(); }
  50
  51     void setContentString(StringImpl*);
  52     StringImpl* contentString() const { return m_contentString.get(); }
  53     // The complete text is all of the text in the associated DOM text node.
  54     PassRefPtr<StringImpl> completeText() const;
  55     // The fragment text is the text which will be used by this LayoutTextFragment. For
  56     // things like first-letter this may differ from the completeText as we maybe using
  57     // only a portion of the text nodes content.
  58
  59     PassRefPtr<StringImpl> originalText() const override;
  60
  61     void setText(PassRefPtr<StringImpl>, bool force = false) override;
  62     void setTextFragment(PassRefPtr<StringImpl>, unsigned start, unsigned length);
  63
  64     void transformText() override;
  65
  66     // FIXME: Rename to LayoutTextFragment
  67     const char* name() const override { return "LayoutTextFragment"; }
  68
  69     void setFirstLetterPseudoElement(FirstLetterPseudoElement* element) { m_firstLetterPseudoElement = element; }
  70     FirstLetterPseudoElement* firstLetterPseudoElement() const { return m_firstLetterPseudoElement; }
  71
  72     void setIsRemainingTextLayoutObject(bool isRemainingText) { m_isRemainingTextLayoutObject = isRemainingText; }
  73     bool isRemainingTextLayoutObject() const { return m_isRemainingTextLayoutObject; }
  74
  75 protected:
  76     void willBeDestroyed() override;
  77
  78 private:
  79     LayoutBlock* blockForAccompanyingFirstLetter() const;
  80     UChar previousCharacter() const override;
  81
  82     Text* associatedTextNode() const;
  83     void updateHitTestResult(HitTestResult&, const LayoutPoint&) override;
  84
  85     unsigned m_start;
  86     unsigned m_end;
  87     bool m_isRemainingTextLayoutObject;
  88     RefPtr<StringImpl> m_contentString;
  89     // Reference back to FirstLetterPseudoElement; cleared by FirstLetterPseudoElement::detach() if
  90     // it goes away first.
  91     GC_PLUGIN_IGNORE("http://crbug.com/509911")
  92     FirstLetterPseudoElement* m_firstLetterPseudoElement;
  93 };
  94
  95 DEFINE_TYPE_CASTS(LayoutTextFragment, LayoutObject, object, toLayoutText(object)->isTextFragment(), toLayoutText(object).isTextFragment());
  96
  97 } // namespace blink
  98
  99 #endif // LayoutTextFragment_h