[Qt-qml] How to spawn N8 Apps from within QML?

[Niels Mayer]

On Mon, Nov 8, 2010 at 2:45 AM,  <Andrew.Ratcliff at nokia.com> wrote:
> How would I spawn other Symbian (N8) applications like Messaging, Contacts
> etc. from within my QML?

I've been wondering about this myself in the context of
http://ytd-meego.googlecode.com . Rather than linking in all sorts of
specialized tightly threaded media-handling code, some apps might work
best by invoking and controlling single-purpose specialized
command-line progs that execute as a subprocess, e.g. for capturing,
encoding, playing back of media.

Seems like QtQuick/QML ought to have a "declarative subprocess"
facility as well. (Or maybe it does and i didn't see it documented
anywhere?) This would allow launching of subprocesses asynchronously,
using  "declarative" statements to handle changing application state
based on the subprocess. Subprocess state changes are expressed via
high-level messages such as: BeforeProcessExit AfterProcessExit,
OnOutputLine, OnOutputJSON, OnOutputRegexp, etc.

In Unix, such functionality has long been provided by
http://en.wikipedia.org/wiki/Expect . I think it would be very useful
to have such functionality available in QtQuick/QML. In a distant
past, I found it quite easy to write all manner of GUIs for existing
Unix functionality using an expect-based subprocess facility
integrated into a dynamic object oriented language:
http://nielsmayer.com/winterp/examples/subcalc.lsp
http://nielsmayer.com/winterp/scrnsnaps/subcalc.gif

Niels
http://nielsmayer.com