mobile: not smooth scrolling from dive-detail to dive-detail

[Dirk Hohndel]

> On Feb 10, 2016, at 7:26 AM, Sebastian Kügler <sebas at kde.org> wrote:
>> Tempted by the hypothesis of the slow profile rendering being the the 
>> issue of the "strange scrolling behavior", I did the following 
>> experiment. Commented the entire QMLProfile block (and the references to 
>> it) from the DiveDetails.qml. This does result in a page without the 
>> profile, so, with knowing much about the internals of QML, I assume that 
>> this suppresses any dive profile rendering related computations.
>> 
>> This does not change the strange scrolling behavior.
>> 
>> I agree that the profile rendering is an computational serious effort, 
>> and that asynchronous computation, and caching are very relevant ideas 
>> to tackle this, but I doubt that it touches the "80% scrolling" behavior.
> 
> Hm, I tried this a while ago myself, and back then it had a noticeable 
> effect... I wonder what changed. (It's of course awesome that the profile 
> rendering doesn't seem the culprit anymore.)
> 
> Next thing I can think of is a too complex details page.

That page is very simple. If you watch the effect you'll clearly see that everything 
is rendered already. What I'm wondering is if reaching the "80%" mark triggers
the rendering of the NEXT page in the background (for caching). But I don't know
enough about the QML implementation to make much sense of all this. It definitely
feels awkward.

This is one of the things in QML that are so frustrating - so much of the inner
workings are completely opaque to the developer.

/D