Very bad performance on Android about sharpnado.shadows

[roubachof]

Well you should be doing something wrong. Maybe have a look to the sample which scroll smoothly with more than 20 different shadows displayed. Of course can't do anything without a repro. Also did you use the latest version ?

[Huaba93]

Same problem here. I am using just one shadow and the entire page takes 1-2 MINUTES to render.

I will provide more infos soon

[roubachof]

Also, did you read : https://github.com/roubachof/Sharpnado.Shadows/blob/master/README.md#animating-shadows ?

[Huaba93]

@roubachof I think I was a little too hasty. atm I don't think shadows are causing my problems. It's more a forms 5 + AndroidX issue. i am still investigating

[roubachof]

yup always start by removing shadows and see if the issue is still there x)

[Huaba93]

@roubachof for me there is no problem with shadows ;)

[Tarekka]

@roubachof , thanks for your response.
I actually tried it in another one of my apps and it works perfectly.
But in this app it takes time for some reason.

Any suggestions?
I'm using the latest version by the way, and I'm not animating anything.
Here's my example code:

App.xaml:
<Style ApplyToDerivedTypes="True" TargetType="sh:Shadows"> <Setter Property="CornerRadius" Value="10" /> <Setter Property="Shades"> <sh:ImmutableShades> <sh:Shade BlurRadius="50" Opacity="1" Offset="-10,-10" Color="#80FFFFFF" /> <sh:Shade BlurRadius="50" Opacity="1" Offset="6, 6" Color="#33000000" /> </sh:ImmutableShades> </Setter> </Style>

One of the cells from my test page:
... <sh:Shadows Grid.Column="0" Grid.Row="0" CornerRadius="20" StyleId="Note"> <sh:Shadows.GestureRecognizers><TapGestureRecognizer NumberOfTapsRequired="1" Tapped="TapGestureRecognizer_Tapped"/></sh:Shadows.GestureRecognizers> <StackLayout BackgroundColor="#F0F0F3" Grid.Column="0" Padding="10" > <Label Text="&#xf249;" TextColor="{StaticResource primary}" FontSize="40" FontFamily="{StaticResource FontAwesomeSolid}" HorizontalOptions="Center" HorizontalTextAlignment="Center" VerticalTextAlignment="Center"/> <Label Text="Note" HorizontalOptions="Center" HorizontalTextAlignment="Center"/> </StackLayout> </sh:Shadows> ...

Output:

EDIT: and yes, when I remove the shadows everything works fine

[roubachof]

sorry but:

1. your xaml is not even formatted: it's unreadable
2. shadows are costly to render so I guess when you are clicking the button, the view build time is causing this lag

You can either prerender your view then translate by the y axis when clicking the button.
Or use the LazyView on the "common" page, and call Load on the LazyView when the page is loaded:

https://www.sharpnado.com/xamarin-forms-lazyview-boost-your-app-reactivity-and-startup-time/

In all case, it's not a performance issue with shadows but a question of architecture and layout timing.