Sharpnado.MaterialFrame

Get it from NuGet:

Initialization

• On Core project in App.xaml.cs:

For the namespace xaml schema to work (remove duplicates xml namespace: see this xamarin doc), you need to call tabs and shadows initializers from the App.xaml.cs file like this:

public App()
{
    InitializeComponent();

    Sharpnado.MaterialFrame.Initializer.Initialize(loggerEnable: false);
    ...
}

• On iOS add this line after Xamarin.Forms.Forms.Init() and before LoadApplication(new App()).

iOSMaterialFrameRenderer.Init();

• On macOS add this line after Xamarin.Forms.Forms.Init() and before LoadApplication(new App()).

macOSMaterialFrameRenderer.Init();

• On UWP, you must register the renderers assembly like this, before Xamarin.Forms.Forms.Init():

var rendererAssemblies = new[] { typeof(UWPMaterialFrameRenderer).GetTypeInfo().Assembly };

Android Compatibility issues

Warning, because of LayerDrawable the Acrylic glow effect (the white glow on the top of the MaterialFrame is only available on API 23+ (since Marshmallow).

Presentation

The Xamarin.Forms MaterialFrame aims at delivering out of the box modern popular theming such as:

• Light
• Dark
• Acrylic
• AcrylicBlur

You can switch from one theme to another thanks to the MaterialFrame property.

Sample Apps

The MaterialFrame is extensively used in the Sharpnado.Acrylic and the Xamarin-Forms-Practices sample apps.

MaterialTheme

Light

In light theme, you can set the LightThemeBackgroundColor and control the Elevation.

Dark

In dark theme, you can only control the Elevation, more elevation equals more light on the black frame (see below).

Acrylic

In Acrylic theme, you can still set the LightThemeBackgroundColor, also a Color of F1F1F1 is advised to have a good Acrylic effect.

AcrylicBlur

In AcrylicBlur theme, LightThemeBackgroundColor and Elevation properties are discarded.

You can set the BlurStyle property for both Android and iOS.

REMARK: On Android go easy on the blur: it's a resource intensive operation. For each blurred frame, it will go trough all the view hierarchy from the root view to the target view.

Light

ExtraLight

Dark

UWP specific properties

UWP is the home of the Acrylic effect \o/

UwpBlurOverlayColor

UWP only.

Changes the overlay color over the blur (should be a transparent color, obviously). If not set, the different blur style styles take over.

Android specific properties

Because the Android version is a custom blur implementation, you have access to some fine tuning properties.

AndroidBlurOverlayColor

Android only.

Changes the overlay color over the blur (should be a transparent color, obviously). If not set, the different blur style styles take over.

AndroidBlurRadius

Android only.

Changes the blur radius on Android. If set, it takes precedence over MaterialBlurStyle. If not set, the different blur style styles take over.

AndroidBlurRootElement (Performance)

Android only: the root element must be an ancestor of the MaterialFrame.

Blur computation is very costly on Android since it needs to process all the view hierarchy from the root element to be blurred (most of the time the element displaying the underlying image) to the blur frame. The shorter the path, the better the performance. If no root element is set, the activity decor view is used.

Android renderer configuration

You can configure 2 different static properties on the Android renderer:

AndroidMaterialFrameRenderer.BlurAutoUpdateDelayMilliseconds

When a page visibility changes we activate or deactivate blur updates. Setting a bigger delay could improve performance and rendering.

AndroidMaterialFrameRenderer.BlurProcessingDelayMilliseconds

Sometimes the computation of the background can take some times (svg images for example). Setting a bigger delay to be sure that the background is rendered first can fix some glitches.

AndroidMaterialFrameRenderer.ThrowStopExceptionOnDraw

If set to true, the rendering result could be better (clearer blur not mixing front elements). However due to a bug in the Xamarin framework xamarin/xamarin-android#4548, debugging is impossible with this mode (causes SIGSEGV). My suggestion would be to set it to false for debug, and to true for releases.

LightThemeBackgroundColor

The background color in Light and Acrylic themes. In Dark theme, this value is ignored because the background color depends on the Elevation. In AcrylicBlur, the value is discarded cause iOS doesn't allow you to control the overlay color. Note that setting the BackgroundColor property has no effect with the MaterialFrame.

AcrylicGlowColor

You can change the "glow" of a MaterialFrame with an acrylic theme (the thin top white glow). Default is white. This property is ignored is the theme is not set to Acrylic.

Elevation

This property semantic changes according to the theme currently set:

Light Theme

Cast a shadow according to Google's Material elevation specs.

Dark Theme

Change the frame's background color according to Google's dark mode specs:

Acrylic Theme

Property is ignored and a custom shadow is applied.

AcrylicBlur Theme

Property is ignored, no shadow is cast.

CornerRadius

Same as the Xamarin.Forms Frame here.

Changing theme for every frames

You either use DynamicResource as explained in my previous post.

Or use the static method called ChangeGlobalTheme(Theme newTheme). Setting a new theme on this method will change the MaterialTheme of every MaterialFrame of your app.

Examples of styles

Acrylic style

From Sharpnado.Acrylic github repo, MaterialFrame.xaml file:

<ResourceDictionary xmlns="http://xamarin.com/schemas/2014/forms"
                    xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
                    xmlns:rv="clr-namespace:Sharpnado.MaterialFrame;assembly=Sharpnado.MaterialFrame">

    <ResourceDictionary.MergedDictionaries>
        <ResourceDictionary Source="Colors.xaml" />
    </ResourceDictionary.MergedDictionaries>

    <Style TargetType="rv:MaterialFrame">
        <Setter Property="MaterialTheme" Value="Acrylic" />
        <Setter Property="Margin" Value="5, 5, 5, 10" />
        <Setter Property="Padding" Value="20,15" />
        <Setter Property="CornerRadius" Value="10" />
        <Setter Property="LightThemeBackgroundColor" Value="{StaticResource AcrylicFrameBackgroundColor}" />
    </Style>

</ResourceDictionary>

Color.xaml file:

<?xml version="1.0" encoding="UTF-8" ?>
<?xaml-comp compile="true" ?>

<ResourceDictionary xmlns="http://xamarin.com/schemas/2014/forms" xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml">

    <Color x:Key="AcrylicSurface">#E6E6E6</Color>

    <Color x:Key="AcrylicFrameBackgroundColor">#F1F1F1</Color>

    <Color x:Key="AccentColor">#00E000</Color>

    <Color x:Key="PrimaryColor">Black</Color>
    <Color x:Key="SecondaryColor">#60000000</Color>
    <Color x:Key="TernaryColor">#30000000</Color>

    <Color x:Key="TextPrimaryColor">Black</Color>
    <Color x:Key="TextSecondaryColor">#60000000</Color>
    <Color x:Key="TextTernaryColor">#40000000</Color>

</ResourceDictionary>

Dynamic styles

From the Silly App! github repository.

MaterialFrame xaml:

    <renderedViews:MaterialFrame
        Margin="0,16"
        Padding="16,10"
        Elevation="4"
        LightThemeBackgroundColor="{DynamicResource DynamicLightThemeColor}"
        CornerRadius="{DynamicResource DynamicCornerRadius}"
        MaterialTheme="{DynamicResource DynamicMaterialTheme}" />

Styles:

    <Color x:Key="DarkSurface">#121212</Color>
    <Color x:Key="LightSurface">#02FF0266</Color>
    <Color x:Key="AcrylicSurface">#E4E4E4</Color>

    <Color x:Key="OnSurfaceColor">#FFFFFF</Color>
    <Color x:Key="AcrylicFrameBackgroundColor">#F1F1F1</Color>

Theme switching code:

    public static void SetDarkMode()
    {
        // MaterialFrame.ChangeGlobalTheme(MaterialFrame.Theme.Dark);
        SetDynamicResource(DynamicMaterialTheme, MaterialFrame.Theme.Dark);

        SetDynamicResource(DynamicBackgroundColor, "DarkSurface");
        SetDynamicResource(DynamicCornerRadius, 5);
    }

    public static void SetLightMode(bool isAcrylic)
    {
        // MaterialFrame.ChangeGlobalTheme(isAcrylic ? MaterialFrame.Theme.Acrylic : MaterialFrame.Theme.Light);
        SetDynamicResource(DynamicMaterialTheme, isAcrylic ? MaterialFrame.Theme.Acrylic : MaterialFrame.Theme.Light);

        SetDynamicResource(DynamicBackgroundColor, isAcrylic ? "AcrylicSurface" : "LightSurface");
        SetDynamicResource(DynamicLightThemeColor, isAcrylic ? "AcrylicFrameBackgroundColor" : "OnSurfaceColor");
        SetDynamicResource(DynamicCornerRadius, isAcrylic ? 10 : 5);
    }

Know Issues

iOS

For some yet to be discovered reasons, AcrylicBlur value doesn't work in a dynamic context on iOS.

You can change the BlurStyle dynamically, but a dynamic change from a not blurry theme to the AcrylicBlur theme will result in a transparent frame.

Android

Sometimes the Android emulator can stall due to too many AcrylicBlur frames displaying at the same time.

Performance for Acrylic mode

To achieve the nice white glow effect, the first idea was to use two Xamarin.Forms Frame stacked. The first one white, and the second one on top painted with the LightThemeBackgroundColor. This was quite hacky and not really stable (for example assigning BindableProperty inside of the object embedding those properties break the property changed events in the renderers).

I then plan to use 2 Frame on Android and 2 UIViews on iOS on the respective renderers. But I didn't like the idea of stacking 2 views, that didn't seem a good tradeoff since now I was moving to the renderers world...

I finally find a way to have a unique view in each of the renderer:

1. LayerDrawable on Android
2. CALayer on iOS

Doing that only one view is used and only the background changes thanks to these lightweight objects.

License

The blurring implementation on Android is a c# port of the popular RealtimeBlurView.

Copyright 2016 Tu Yimin (http://github.com/mmin18)

Licensed under the Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0);