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Mathematical content (provided as MathML) is now supported in Google Chrome. (#7184)
In Chrome, we use exactly the same code to retrieve MathML as we do in Firefox, so move the math code from NVDAObjects.IAccessible.mozilla into NVDAObjects.IAccessible.ia2Web (which is used by both Firefox and Chrome). We also catch COMError because this isn't yet in Chrome stable and because this can fail in Firefox too if the ISimpleDOM COM proxy isn't registered.
1 parent e82c068 commit 8416a4d

3 files changed

Lines changed: 37 additions & 27 deletions

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‎source/NVDAObjects/IAccessible/ia2Web.py‎

Lines changed: 34 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -2,14 +2,17 @@
22
#A part of NonVisual Desktop Access (NVDA)
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#This file is covered by the GNU General Public License.
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#See the file COPYING for more details.
5-
#Copyright (C) 2006-2015 NV Access Limited
5+
#Copyright (C) 2006-2017 NV Access Limited
66

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"""Base classes with common support for browsers exposing IAccessible2.
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"""
99

10+
from ctypes import c_short
11+
from comtypes import COMError, BSTR
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import oleacc
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import IAccessibleHandler
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import controlTypes
15+
from logHandler import log
1316
from NVDAObjects.behaviors import Dialog
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from . import IAccessible
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from .ia2TextMozilla import MozillaCompoundTextInfo
@@ -48,6 +51,34 @@ class Editor(Ia2Web):
4851
class EditorChunk(Ia2Web):
4952
beTransparentToMouse = True
5053

54+
class Math(Ia2Web):
55+
56+
def _get_mathMl(self):
57+
from comtypes.gen.ISimpleDOM import ISimpleDOMNode
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try:
59+
node = self.IAccessibleObject.QueryInterface(ISimpleDOMNode)
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# Try the data-mathml attribute.
61+
attrNames = (BSTR * 1)("data-mathml")
62+
namespaceIds = (c_short * 1)(0)
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attr = node.attributesForNames(1, attrNames, namespaceIds)
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if attr:
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import mathPres
66+
if not mathPres.getLanguageFromMath(attr) and self.language:
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attr = mathPres.insertLanguageIntoMath(attr, self.language)
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return attr
69+
if self.IA2Attributes.get("tag") != "math":
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# This isn't MathML.
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raise LookupError
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if self.language:
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attrs = ' xml:lang="%s"' % self.language
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else:
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attrs = ""
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return "<math%s>%s</math>" % (attrs, node.innerHTML)
77+
except COMError:
78+
log.debugWarning("Error retrieving math. "
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"Not supported in this browser or ISimpleDOM COM proxy not registered.", exc_info=True)
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raise LookupError
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def findExtraOverlayClasses(obj, clsList, baseClass=Ia2Web, documentClass=None):
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"""Determine the most appropriate class if this is an IA2 web object.
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This should be called after finding any classes for the specific web implementation.
@@ -64,6 +95,8 @@ def findExtraOverlayClasses(obj, clsList, baseClass=Ia2Web, documentClass=None):
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clsList.append(BlockQuote)
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elif iaRole == oleacc.ROLE_SYSTEM_ALERT:
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clsList.append(Dialog)
98+
elif iaRole == oleacc.ROLE_SYSTEM_EQUATION:
99+
clsList.append(Math)
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isApp = iaRole in (oleacc.ROLE_SYSTEM_APPLICATION, oleacc.ROLE_SYSTEM_DIALOG)
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if isApp:

‎source/NVDAObjects/IAccessible/mozilla.py‎

Lines changed: 2 additions & 25 deletions
Original file line numberDiff line numberDiff line change
@@ -3,14 +3,13 @@
33
#A part of NonVisual Desktop Access (NVDA)
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#This file is covered by the GNU General Public License.
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#See the file COPYING for more details.
6-
#Copyright (C) 2006-2015 NV Access Limited, Peter Vágner
6+
#Copyright (C) 2006-2017 NV Access Limited, Peter Vágner
77

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from collections import namedtuple
9-
from ctypes import c_short
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import IAccessibleHandler
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import oleacc
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import winUser
13-
from comtypes import IServiceProvider, COMError, BSTR
12+
from comtypes import IServiceProvider, COMError
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import eventHandler
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import controlTypes
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from . import IAccessible, Dialog, WindowRoot
@@ -156,27 +155,6 @@ class TextLeaf(Mozilla):
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role = controlTypes.ROLE_STATICTEXT
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beTransparentToMouse = True
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159-
class Math(Mozilla):
160-
161-
def _get_mathMl(self):
162-
from comtypes.gen.ISimpleDOM import ISimpleDOMNode
163-
node = self.IAccessibleObject.QueryInterface(ISimpleDOMNode)
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# Try the data-mathml attribute.
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attr = node.attributesForNames(1, (BSTR * 1)("data-mathml"), (c_short * 1)(0,))
166-
if attr:
167-
import mathPres
168-
if not mathPres.getLanguageFromMath(attr) and self.language:
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attr = mathPres.insertLanguageIntoMath(attr, self.language)
170-
return attr
171-
if self.IA2Attributes.get("tag") != "math":
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# This isn't MathML.
173-
raise LookupError
174-
if self.language:
175-
attrs = ' xml:lang="%s"' % self.language
176-
else:
177-
attrs = ""
178-
return "<math%s>%s</math>" % (attrs, node.innerHTML)
179-
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def findExtraOverlayClasses(obj, clsList):
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"""Determine the most appropriate class if this is a Mozilla object.
182160
This works similarly to L{NVDAObjects.NVDAObject.findOverlayClasses} except that it never calls any other findOverlayClasses method.
@@ -238,7 +216,6 @@ def findExtraOverlayClasses(obj, clsList):
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IAccessibleHandler.IA2_ROLE_EMBEDDED_OBJECT: EmbeddedObject,
239217
"embed": EmbeddedObject,
240218
"object": EmbeddedObject,
241-
oleacc.ROLE_SYSTEM_EQUATION: Math,
242219
}
243220

244221
#: Roles that mightn't set the focused state when they are focused.

‎user_docs/en/userGuide.t2t‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -543,7 +543,7 @@ This requires that MathPlayer 4 is installed on the computer.
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MathPlayer is available as a free download from: http://www.dessci.com/en/products/mathplayer/
544544

545545
NVDA supports the following types of mathematical content:
546-
- MathML in Mozilla Firefox and Microsoft Internet Explorer.
546+
- MathML in Mozilla Firefox, Microsoft Internet Explorer and Google Chrome.
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- Design Science MathType in Microsoft Word and PowerPoint. MathType needs to be installed in order for this to work. The trial version is sufficient.
548548
- MathML in Adobe Reader. Note that this is not an official standard yet, so there is currently no publicly available software that can produce this content.
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-

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