Re: Recommendations for Firefox key and text events

Hi,

please file bugs on the issues you see.
The right component is probably Event Handling.

Note, DOM 3 Events isn't 100% stable yet, so there will be
changes. But I hope to have some of it implemented in Firefox 4.next.

textInput event has been under discussion, but atm it seems that the
draft specification won't be changed.

Btw, compositionstart/end are dispatched also on Windows.
It all depends on the IME you're using.



-Olli


On 09/30/2010 12:56 AM, Allan Jacobs wrote:
>
> Recommendations
> ===============
> (1) Fix the keyup, keydown, keypress, compositionstart, and
> compositionend events on Linux so that they report something besides 0
> values.  Dead key sequences foul up the assignment of attributes.
> This is #1 because I can probably handle a bug fix of this complexity
> myself.
> (2) Add key and char attributes to key events as per the W3C DOM Level
> 3 Events specification.
> (3) Implement the new textInput event as per the W3C DOM Level 3
> Events specification.
>
> Problems associated with key events are recorded in many bug reports.
> Currently, I've
> been working off of 447757.
>
> Conclusions
> ===========
>
> JavaScript events have attributes.  Mozilla currently does the
> following for key and text events:
>
> (1) Assigns values to the attribute keyCode for keyup and keydown
> events.  The assignment is often wrong (null) on Linux.
> (2) Assigns values to the attribute charCode for keypress events.  The
> assignment is often wrong (null) on Linux.
> (3) Bungles the assignment of attributes to compositionstart and
> compositionend on Linux
>
> The W3C specification declines to specify what the correct values are
> for assignments to charCode and keyCode.  It makes recommendations for
> the assignment of two new attributes: char and key.  In principal,
> these assignments could be made more less operating system and browser
> independent.
>
> (4) Firefox does not make assignments to either of the new char or key
> attributes.  In the tables below, no attempt is made to indicate the
> lack of assignment.  Assignment of both char and key look relatively
> easy.  The previous draft of the W3C DOM Level 3 Events specification
> was more challenging.
>
> (5) Firefox dispatches compositionstart and compositionend events on
> Linux.  On Windows the behavior is completely different.  This is an
> OS dependency that is difficult to code around.
>
> (6) W3C calls for a textInput event to get fired after the last
> keyup.  If Firefox implemented this part of the spec then the OS-
> dependency and browser-dependency it's current implementation is
> requiring could be made to vanish -- at least for the majority of the
> applications that listen to the keyboard.
>
> In an earlier post on this topic, operating system inconsistencies had
> not been determined.  Now they are and they are large.
>
> Supporting Data
> ===============
>
> Mozilla key and text event sequences
> Firefox 3.6.10
> Test URL: https://bug447757.bugzilla.mozilla.org/attachment.cgi?id=474270
>
> Nominal keyboard sequence (Windows: AltGr 2 e)
> Country: Albania
> Language: Albania
>
> The tables record the event sequence in the order of occurence.
>
> Windows
> =======
> keyC charC       alt     event
> 17      -               F       keydown
> 18      -               T       keydown
> 50      -               T       keydown
> 50      -               T       keyup
> 17      -               T       keyup
> 69      -               F       keydown
> -       283             F       keypress
> 69      -               F       keyup
>
> Linux
> =====
> keyCcharC        alt     event
> 0       -               F       keydown
> -       0               T       keypress
> 0       -               T       keyup
> 0       -               T       keyup
> -       -               T       compositionstart
> -       -               F       compositionend
> 69      -               F       keyup
>