ScrollViewer Slow!

Bug Reports
1

Hi, In my app I have a ScrollingAnimation in a ScrollViewer and in the range of the animation the Scroll slow down considerably!

this is the code:

    <ScrollingAnimation From="0" To="250">
        <Scale Target="logo" Factor="0.7" />
        <Change Target="PanelTextInputBusqueda.Height" Value="0" />
        <Change Target="HeaderPagina1.Height" Value="65" />
        <Change Target="PopularMovies.Anchor" Value="50,20" />
        <Change Target="PopularMovies.Opacity" Value="0.4" />
    </ScrollingAnimation>

And here a video of the problem… https://fuseweb.azureedge.net/forum-user-uploads/2016/08/22/WUSl2OmIbfeJ-legacy-files-drGxKB1bU6Mvh2Q7-h-wpKQdSI2PvPRMbXP1tpJMC.mp4

2

The likely source of the problem are the three animators modifying the layout of the UI. Those are at the Height and Anchor properties. In a lot of cases we have optimizations in place to prevent needing to do a completely new layout, but there are obviously scenarios where it’ll do too much.

The way these top regions are done in some of our examples is to avoid needing a new layout on the ScrollView itself. I’m just checking now if we have a published one. It is often the layout of the ScrollView that is most costly.

One of our examples: https://www.fusetools.com/developers/examples/scrollinganimation

If you can show me some more of the UX, or provide a standalone example, then I could also determine where the problem is.

3

Thanks! I will modify the layout like the example. But I test the same app with a old apk (Created with a Fuse version before 0.5.0) and this don’t happen! And in general all the ScrollViewers work more smooth…

4

Yes, it’s certainly possible that something has changed. That’s why a complete example would be great. Often it’s just something small that wasn’t captured in our test cases. Sometimes it’s a fix to another defect that has unintended results on performance.

5

Its hard to me publish my app. There are many files (Uno files, js files). I will try to reprocude the same in a example…

6

I fix the problem replacing all the animation with Move animation. But I have some Horizontal ScrollViewers with a stackPanel inside with many elements that are very slow. In previous version this Scrollviewers are very smooths. Now have many frame drops!