accessible/src/base/nsTextUtils.h

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   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
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  15  * The Original Code is mozilla.org code.
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  19  * Portions created by the Initial Developer are Copyright (C) 2007
  20  * the Initial Developer. All Rights Reserved.
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  22  * Contributor(s):
  23  *   Alexander Surkov <surkov.alexander@gmail.com> (original author)
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  25  * Alternatively, the contents of this file may be used under the terms of
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  37  * ***** END LICENSE BLOCK ***** */
  38
  39 #ifndef nsTextUtils_h_
  40 #define nsTextUtils_h_
  41
  42 #include "nsIDOMElement.h"
  43 #include "nsIDOMCSSStyleDeclaration.h"
  44
  45 #include "nsIContent.h"
  46 #include "nsIFrame.h"
  47
  48 #include "nsCOMPtr.h"
  49 #include "nsString.h"
  50
  51 /**
  52  * Base class to work with text attributes. See derived classes below.
  53  */
  54 class nsTextAttr
  55 {
  56 public:
  57   /**
  58    * Return true if the text attribute for the given element equals with
  59    * predefined attribute.
  60    */
  61   virtual PRBool Equal(nsIDOMElement *aElm) = 0;
  62 };
  63
  64 /**
  65  * Class is used for the work with 'lang' text attributes. Used in
  66  * nsHyperTextAccessible.
  67  */
  68 class nsLangTextAttr : public nsTextAttr
  69 {
  70 public:
  71   nsLangTextAttr(nsAString& aLang, nsIContent *aRootContent) :
  72     mLang(aLang), mRootContent(aRootContent) { }
  73
  74   virtual PRBool Equal(nsIDOMElement *aElm);
  75
  76 private:
  77   nsString mLang;
  78   nsCOMPtr<nsIContent> mRootContent;
  79 };
  80
  81 /**
  82  * Class is used for the work with CSS based text attributes. Used in
  83  * nsHyperTextAccessible.
  84  */
  85 class nsCSSTextAttr : public nsTextAttr
  86 {
  87 public:
  88   nsCSSTextAttr(PRBool aIncludeDefAttrValue, nsIDOMElement *aElm,
  89                 nsIDOMElement *aRootElm);
  90
  91   // nsTextAttr
  92   virtual PRBool Equal(nsIDOMElement *aElm);
  93
  94   // nsCSSTextAttr
  95   /**
  96    * Interates through attributes.
  97    */
  98   PRBool Iterate();
  99
 100   /**
 101    * Get name and value of attribute.
 102    */
 103   PRBool Get(nsACString& aName, nsAString& aValue);
 104
 105 private:
 106   PRInt32 mIndex;
 107   PRBool mIncludeDefAttrValue;
 108
 109   nsCOMPtr<nsIDOMCSSStyleDeclaration> mStyleDecl;
 110   nsCOMPtr<nsIDOMCSSStyleDeclaration> mDefStyleDecl;
 111 };
 112
 113 /**
 114  * Class is used for the work with "background-color" text attribute. It is
 115  * used in nsHyperTextAccessible.
 116  */
 117 class nsBackgroundTextAttr : public nsTextAttr
 118 {
 119 public:
 120   nsBackgroundTextAttr(nsIFrame *aFrame, nsIFrame *aRootFrame);
 121
 122   // nsTextAttr
 123   virtual PRBool Equal(nsIDOMElement *aElm);
 124
 125   /**
 126    * Returns true and background color value if "background-color" text
 127    * attribute should be exposed.
 128    */
 129   virtual PRBool Get(nsAString& aValue);
 130
 131 private:
 132   /**
 133    * Return background color for the given frame.
 134    *
 135    * @note  If background color for the given frame is transparent then walk
 136    *        trhough the frame parents chain until we'll got either a frame with
 137    *        not transparent background color or the given root frame. In the
 138    *        last case return background color for the root frame.
 139    *
 140    * @param aFrame      [in] the given frame to calculate background-color
 141    * @return            background color
 142    */
 143   nscolor GetColor(nsIFrame *aFrame);
 144
 145   nsIFrame *mFrame;
 146   nsIFrame *mRootFrame;
 147 };
 148
 149 #endif