ubuntu-touch-coreapps team mailing list archive

[Roman Shchekin <mrqtros@xxxxxxxxx>]

Hi

Thanks for the answer! But:

> user starts seeing results immediately instead of waiting

Are you sure? In File Manager I can see ActivityIndicator during folder
navigation, without partial displaying of files. Once full amount of data
is retreived, ActivityIndicator is disappear and I can continue my work. So
it *is not responsive* at the moment.

I am pretty sure that perfectly written 'C++ to QML' transition will not
cause such slowness. Maybe someone should profile it? In the latest SDK
profiler and debugger are working out-of-the-box (I was having troubles
with these tools before).

2016-05-15 8:40 GMT+03:00 ajalkane <ajalkane@xxxxxxxxx>:

>
>
> On Sat, May 14, 2016 at 11:30 PM, Roman Shchekin <mrqtros@xxxxxxxxx>
> wrote:
>
>> My question is - *why*? File Manager gets information directly from
>> local file system, while cloud storage client must send network request,
>> receive result, parse JSON. Moreover, File Manager displays static icon for
>> all files, but my client is uses real thumbnails.
>>
>>
> Hi Roman,
>
> I haven't checked your code and it's been awhile since I've checked
> FileManager's code, but I'm giving my best guess here still. Most likely
> the reason for your observation is the overhead between passing data
> between the QML frontend and the C++ backend that retrieves the files. When
> a folder is listed the backend starts doing its work and whenever new file
> is retrieved they're sent to the QML frontend for displaying.
>
> It's a tradeoff between responsiveness (user starts seeing results
> immediately instead of waiting) and total time taken.
>
> This could be improved for example by adding files in chunks instead of
> for each file, thus reducing the signalling overhead between QML and C++.
> Personally I don't think that's worth the added code complexity, but YMMV.
>
> Regards,
> Arto
>
>