[Qt-qml] Any tips or tricks to help with long app startup times?

Pelle Johnsen pelle.johnsen at gmail.com
Tue Sep 27 17:12:40 CEST 2011


>From my experience QML does generally suffer a bit from slow startup time,
especially on embedded platforms :S

In the project I'm working on the 2 main problems we found are:

1. Actually creating instances of QML Items. In a large app. there can be
thousands. This can to some extend be helped by splitting up the app and
sort of delay/demand loading individual parts, so you get the main UI up as
fast as possibly

2. QML Image uses QPixmap which can only be created in the UI thread, making
it impossible to load QML in a background thread (not sure if there is some
changes to this in 4.8). If you are doing custom Ui you probably have lots
of images, which do take time to load up.

Also see this forum thread:
http://developer.qt.nokia.com/forums/viewthread/3144

 -Pelle

On Tue, Sep 27, 2011 at 4:58 PM, Todd Rose <teeceeare97 at gmail.com> wrote:

> We have a relatively large qt-qml application.  The back-end is C++
> and front-end ui is about 70 or so QML files.  We're currently seeing
> very long initial startup times (ten seconds or more) and we'd like to
> know if there's any simple things that we can do to mitigate this.
> Some of it is in our application domain and we're working on that
> part, but the actual loading and rendering of the QML is also a quite
> significant portion of overall initial startup time.  Are there any
> tricks to make loading and initializing the qt and qtmobility
> libraries faster?  What about the initial QML file load/parse phase?
> We have all of our resource files stored in application subdirectories
> - would packaging them in a qt resource file make any difference here?
>
> Thanks in advance,
> Todd
> _______________________________________________
> Qt-qml mailing list
> Qt-qml at qt.nokia.com
> http://lists.qt.nokia.com/mailman/listinfo/qt-qml
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.qt.nokia.com/pipermail/qt-qml/attachments/20110927/9230f9c1/attachment.html 


More information about the Qt-qml mailing list