Qt AT-SPI 2 Bridge

Info

This is about the Qt AT-SPI 2 bridge. The bridge is a Qt Accessibility plugin that exposes the internals of a Qt application to interested accessibility clients such as screenreaders.

AT-SPI on D-Bus at Linuxfoundation

The source code for the bridge can be found here: Qt AT-SPI on gitorious

Tools

With the Gnome efforts to implement AT-SPI 2 we have some really helpful tools:

Accerciser accerciser manual

Orca Orca Debugging

Tutorial on techbase

Python

Testing/Development

You need a very recent environment, most notably: pyatspi2, at-spi2-core and at-spi2-atk

Inside a Gnome session the a11y uses a dedicated d-bus. So if you want to monitor what is going on, you should use: dbus-monitor --address `xprop -root | grep AT_SPI_BUS | sed -e 's/.*= "//' | sed -e 's/"$//'`

Todo

Complex widgets with children? Tabs... clicking on a file in qgit (crash fix committed, but still needs proper fix)

GetApplicationBusAddress seems not defined in the xml but is actually called mgorse: That ought to be defined in the xml. It is used to try to set up a direct dbus connection between libatspi and the application. libatspi will revert to using the session bus if it returns an empty string or an error

don't pretend to be gail, coordinate with orca devels
Test apps with >1 window

fix action for menus inside qt
scroll bars have value interface but don't update and cannot be updated, value interface in general
text attributes (bold etc)
tabs

Widgets

Combobox
List
Tree
Table
Spinner
Scrollbar

KDE Widgets

Widget	Status
ExampleWidget1	Ready.
ExampleWidget2	Mostly done, still needs fooBar() call.
KCharSelect	Unknown
KColorButton	Unknown
KColorCombo	Unknown
KComboBox	Unknown
KCModule	Unknown
KDateWidget	Unknown
KDatePicker	Unknown
KDialog	Unknown
KEditListBox	Unknown
KFontComboBox	Unknown
KFontChooser	Unknown
KFontRequester	Unknown
KGradientSelector	Unknown
KHistoryComboBox	Unknown
KHueSaturationSelector	Unknown
KHtmlView	Unknown
KLed	Unknown
KListWidget	Unknown
KLineEdit	Unknown
KPushButton	Unknown
KRestrictedLine	Unknown
KIntSpinBox	Unknown
KRuler	Unknown
KSqueezedTextLabel	Unknown
KTextBrowser	Unknown
KTextEdit	Unknown
KURLLabel	Unknown
KURLComboRequester	Unknown
KURLRequester	Unknown
KIntNumInput	Unknown
KDoubleNumInput	Unknown
KDateTimeWidget	Unknown
KDateTable	Unknown

Memory Management

Qt's current QAccessibleInterface is a pain to deal with.

We can only (safely?) hold on to interfaces created by navigate or queryInterface
Interfaces that we get through notifyAccessibility are deleted by Qt behind our back, so we need to never keep those around (Frederik will try to fix that now)