gecko-dev/accessible/base/TextAttrs.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef nsTextAttrs_h_
#define nsTextAttrs_h_
#include "mozilla/FontPropertyTypes.h"
#include "nsCOMPtr.h"
#include "nsColor.h"
#include "nsString.h"
#include "nsStyleConsts.h"
class nsIFrame;
class nsIContent;
class nsDeviceContext;
namespace mozilla {
namespace a11y {
class AccAttributes;
class LocalAccessible;
class HyperTextAccessible;
/**
* Used to expose text attributes for the hyper text accessible (see
* HyperTextAccessible class).
*
* @note "invalid: spelling" text attribute is implemented entirely in
* HyperTextAccessible class.
*/
class TextAttrsMgr {
public:
/**
* Constructor. Used to expose default text attributes.
*/
explicit TextAttrsMgr(HyperTextAccessible* aHyperTextAcc)
: mOffsetAcc(nullptr),
mHyperTextAcc(aHyperTextAcc),
mOffsetAccIdx(-1),
mIncludeDefAttrs(true) {}
/**
* Constructor. Used to expose text attributes at the given offset.
*
* @param aHyperTextAcc [in] hyper text accessible text attributes are
* calculated for
* @param aIncludeDefAttrs [optional] indicates whether default text
* attributes should be included into list of exposed
* text attributes
* @param oOffsetAcc [optional] offset an accessible the text attributes
* should be calculated for
* @param oOffsetAccIdx [optional] index in parent of offset accessible
*/
TextAttrsMgr(HyperTextAccessible* aHyperTextAcc, bool aIncludeDefAttrs,
LocalAccessible* aOffsetAcc, int32_t aOffsetAccIdx)
: mOffsetAcc(aOffsetAcc),
mHyperTextAcc(aHyperTextAcc),
mOffsetAccIdx(aOffsetAccIdx),
mIncludeDefAttrs(aIncludeDefAttrs) {}
/*
* Return text attributes and hyper text offsets where these attributes are
* applied. Offsets are calculated in the case of non default attributes.
*
* @note In the case of default attributes pointers on hyper text offsets
* must be skipped.
*
* @param aAttributes [in, out] text attributes list
* @param aStartHTOffset [out, optional] start hyper text offset
* @param aEndHTOffset [out, optional] end hyper text offset
*/
void GetAttributes(AccAttributes* aAttributes,
uint32_t* aStartHTOffset = nullptr,
uint32_t* aEndHTOffset = nullptr);
protected:
/**
* Calculates range (start and end offsets) of text where the text attributes
* are stretched. New offsets may be smaller if one of text attributes changes
* its value before or after the given offsets.
*
* @param aTextAttrArray [in] text attributes array
* @param aAttrArrayLen [in] text attributes array length
* @param aStartHTOffset [in, out] the start offset
* @param aEndHTOffset [in, out] the end offset
*/
class TextAttr;
void GetRange(TextAttr* aAttrArray[], uint32_t aAttrArrayLen,
uint32_t* aStartOffset, uint32_t* aEndOffset);
private:
LocalAccessible* mOffsetAcc;
HyperTextAccessible* mHyperTextAcc;
int32_t mOffsetAccIdx;
bool mIncludeDefAttrs;
protected:
/**
* Interface class of text attribute class implementations.
*/
class TextAttr {
public:
/**
* Expose the text attribute to the given attribute set.
*
* @param aAttributes [in] the given attribute set
* @param aIncludeDefAttrValue [in] if true then attribute is exposed even
* if its value is the same as default one
*/
virtual void Expose(AccAttributes* aAttributes,
bool aIncludeDefAttrValue) = 0;
/**
* Return true if the text attribute value on the given element equals with
* predefined attribute value.
*/
virtual bool Equal(LocalAccessible* aAccessible) = 0;
};
/**
* Base class to work with text attributes. See derived classes below.
*/
template <class T>
class TTextAttr : public TextAttr {
public:
explicit TTextAttr(bool aGetRootValue) : mGetRootValue(aGetRootValue) {}
// TextAttr
virtual void Expose(AccAttributes* aAttributes,
bool aIncludeDefAttrValue) override {
if (mGetRootValue) {
if (mIsRootDefined) ExposeValue(aAttributes, mRootNativeValue);
return;
}
if (mIsDefined) {
if (aIncludeDefAttrValue || mRootNativeValue != mNativeValue) {
ExposeValue(aAttributes, mNativeValue);
}
return;
}
if (aIncludeDefAttrValue && mIsRootDefined) {
ExposeValue(aAttributes, mRootNativeValue);
}
}
virtual bool Equal(LocalAccessible* aAccessible) override {
T nativeValue;
bool isDefined = GetValueFor(aAccessible, &nativeValue);
if (!mIsDefined && !isDefined) return true;
if (mIsDefined && isDefined) return nativeValue == mNativeValue;
if (mIsDefined) return mNativeValue == mRootNativeValue;
return nativeValue == mRootNativeValue;
}
protected:
// Expose the text attribute with the given value to attribute set.
virtual void ExposeValue(AccAttributes* aAttributes, const T& aValue) = 0;
// Return native value for the given DOM element.
virtual bool GetValueFor(LocalAccessible* aAccessible, T* aValue) = 0;
// Indicates if root value should be exposed.
bool mGetRootValue;
// Native value and flag indicating if the value is defined (initialized in
// derived classes). Note, undefined native value means it is inherited
// from root.
MOZ_INIT_OUTSIDE_CTOR T mNativeValue;
MOZ_INIT_OUTSIDE_CTOR bool mIsDefined;
// Native root value and flag indicating if the value is defined
// (initialized in derived classes).
MOZ_INIT_OUTSIDE_CTOR T mRootNativeValue;
MOZ_INIT_OUTSIDE_CTOR bool mIsRootDefined;
};
/**
* Class is used for the work with 'language' text attribute.
*/
class LangTextAttr : public TTextAttr<nsString> {
public:
LangTextAttr(HyperTextAccessible* aRoot, nsIContent* aRootElm,
nsIContent* aElm);
virtual ~LangTextAttr();
protected:
// TextAttr
virtual bool GetValueFor(LocalAccessible* aAccessible,
nsString* aValue) override;
virtual void ExposeValue(AccAttributes* aAttributes,
const nsString& aValue) override;
private:
nsCOMPtr<nsIContent> mRootContent;
};
/**
* Class is used for the 'invalid' text attribute. Note, it calculated
* the attribute from aria-invalid attribute only; invalid:spelling attribute
* calculated from misspelled text in the editor is managed by
* HyperTextAccessible and applied on top of the value from aria-invalid.
*/
class InvalidTextAttr : public TTextAttr<uint32_t> {
public:
InvalidTextAttr(nsIContent* aRootElm, nsIContent* aElm);
virtual ~InvalidTextAttr(){};
protected:
enum { eFalse, eGrammar, eSpelling, eTrue };
// TextAttr
virtual bool GetValueFor(LocalAccessible* aAccessible,
uint32_t* aValue) override;
virtual void ExposeValue(AccAttributes* aAttributes,
const uint32_t& aValue) override;
private:
bool GetValue(nsIContent* aElm, uint32_t* aValue);
nsIContent* mRootElm;
};
/**
* Class is used for the work with 'background-color' text attribute.
*/
class BGColorTextAttr : public TTextAttr<nscolor> {
public:
BGColorTextAttr(nsIFrame* aRootFrame, nsIFrame* aFrame);
virtual ~BGColorTextAttr() {}
protected:
// TextAttr
virtual bool GetValueFor(LocalAccessible* aAccessible,
nscolor* aValue) override;
virtual void ExposeValue(AccAttributes* aAttributes,
const nscolor& aValue) override;
private:
bool GetColor(nsIFrame* aFrame, nscolor* aColor);
nsIFrame* mRootFrame;
};
/**
* Class is used for the work with 'color' text attribute.
*/
class ColorTextAttr : public TTextAttr<nscolor> {
public:
ColorTextAttr(nsIFrame* aRootFrame, nsIFrame* aFrame);
virtual ~ColorTextAttr() {}
protected:
// TTextAttr
virtual bool GetValueFor(LocalAccessible* aAccessible,
nscolor* aValue) override;
virtual void ExposeValue(AccAttributes* aAttributes,
const nscolor& aValue) override;
};
/**
* Class is used for the work with "font-family" text attribute.
*/
class FontFamilyTextAttr : public TTextAttr<nsString> {
public:
FontFamilyTextAttr(nsIFrame* aRootFrame, nsIFrame* aFrame);
virtual ~FontFamilyTextAttr() {}
protected:
// TTextAttr
virtual bool GetValueFor(LocalAccessible* aAccessible,
nsString* aValue) override;
virtual void ExposeValue(AccAttributes* aAttributes,
const nsString& aValue) override;
private:
bool GetFontFamily(nsIFrame* aFrame, nsString& aFamily);
};
/**
* Class is used for the work with "font-size" text attribute.
*/
class FontSizeTextAttr : public TTextAttr<nscoord> {
public:
FontSizeTextAttr(nsIFrame* aRootFrame, nsIFrame* aFrame);
virtual ~FontSizeTextAttr() {}
protected:
// TTextAttr
virtual bool GetValueFor(LocalAccessible* aAccessible,
nscoord* aValue) override;
virtual void ExposeValue(AccAttributes* aAttributes,
const nscoord& aValue) override;
private:
nsDeviceContext* mDC;
};
/**
* Class is used for the work with "font-style" text attribute.
*/
class FontStyleTextAttr : public TTextAttr<mozilla::FontSlantStyle> {
public:
FontStyleTextAttr(nsIFrame* aRootFrame, nsIFrame* aFrame);
virtual ~FontStyleTextAttr() {}
protected:
// TTextAttr
virtual bool GetValueFor(LocalAccessible* aContent,
mozilla::FontSlantStyle* aValue) override;
virtual void ExposeValue(AccAttributes* aAttributes,
const mozilla::FontSlantStyle& aValue) override;
};
/**
* Class is used for the work with "font-weight" text attribute.
*/
class FontWeightTextAttr : public TTextAttr<mozilla::FontWeight> {
public:
FontWeightTextAttr(nsIFrame* aRootFrame, nsIFrame* aFrame);
virtual ~FontWeightTextAttr() {}
protected:
// TTextAttr
virtual bool GetValueFor(LocalAccessible* aAccessible,
mozilla::FontWeight* aValue) override;
virtual void ExposeValue(AccAttributes* aAttributes,
const mozilla::FontWeight& aValue) override;
private:
mozilla::FontWeight GetFontWeight(nsIFrame* aFrame);
};
/**
* Class is used for the work with 'auto-generated' text attribute.
*/
class AutoGeneratedTextAttr : public TTextAttr<bool> {
public:
AutoGeneratedTextAttr(HyperTextAccessible* aHyperTextAcc,
LocalAccessible* aAccessible);
virtual ~AutoGeneratedTextAttr() {}
protected:
// TextAttr
virtual bool GetValueFor(LocalAccessible* aAccessible,
bool* aValue) override;
virtual void ExposeValue(AccAttributes* aAttributes,
const bool& aValue) override;
};
/**
* TextDecorTextAttr class is used for the work with
* "text-line-through-style", "text-line-through-color",
* "text-underline-style" and "text-underline-color" text attributes.
*/
class TextDecorValue {
public:
TextDecorValue()
: mColor{0},
mLine{StyleTextDecorationLine::NONE},
mStyle{NS_STYLE_TEXT_DECORATION_STYLE_NONE} {}
explicit TextDecorValue(nsIFrame* aFrame);
nscolor Color() const { return mColor; }
uint8_t Style() const { return mStyle; }
bool IsDefined() const { return IsUnderline() || IsLineThrough(); }
bool IsUnderline() const {
return bool(mLine & mozilla::StyleTextDecorationLine::UNDERLINE);
}
bool IsLineThrough() const {
return bool(mLine & mozilla::StyleTextDecorationLine::LINE_THROUGH);
}
bool operator==(const TextDecorValue& aValue) {
return mColor == aValue.mColor && mLine == aValue.mLine &&
mStyle == aValue.mStyle;
}
bool operator!=(const TextDecorValue& aValue) { return !(*this == aValue); }
private:
nscolor mColor;
mozilla::StyleTextDecorationLine mLine;
uint8_t mStyle;
};
class TextDecorTextAttr : public TTextAttr<TextDecorValue> {
public:
TextDecorTextAttr(nsIFrame* aRootFrame, nsIFrame* aFrame);
virtual ~TextDecorTextAttr() {}
protected:
// TextAttr
virtual bool GetValueFor(LocalAccessible* aAccessible,
TextDecorValue* aValue) override;
virtual void ExposeValue(AccAttributes* aAttributes,
const TextDecorValue& aValue) override;
};
/**
* Class is used for the work with "text-position" text attribute.
*/
enum TextPosValue {
eTextPosNone = 0,
eTextPosBaseline,
eTextPosSub,
eTextPosSuper
};
class TextPosTextAttr : public TTextAttr<TextPosValue> {
public:
TextPosTextAttr(nsIFrame* aRootFrame, nsIFrame* aFrame);
virtual ~TextPosTextAttr() {}
protected:
// TextAttr
virtual bool GetValueFor(LocalAccessible* aAccessible,
TextPosValue* aValue) override;
virtual void ExposeValue(AccAttributes* aAttributes,
const TextPosValue& aValue) override;
private:
TextPosValue GetTextPosValue(nsIFrame* aFrame) const;
};
}; // TextAttrMgr
} // namespace a11y
} // namespace mozilla
#endif