Accessibility/qt-atspi

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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


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)