'Xamarin Frame only have a single rounded corner

Simple question. I need a frame with only one rounded corner, instead of all four. How can I only round one of the corners of a frame (top right in my case)?

Another way to phrase it: How can I set the cornerradius of only one corner of a frame?

Solution 1:^[1]

Another way it to use custom render for frame.

1.Create class name CustomFrame, inherit Frame class, add BindableProperty CornerRadiusProperty in PCL.

 public class CustomFrame: Frame
{
    public static new readonly BindableProperty CornerRadiusProperty = BindableProperty.Create(nameof(CustomFrame), typeof(CornerRadius), typeof(CustomFrame));
    public CustomFrame()
    {
        // MK Clearing default values (e.g. on iOS it's 5)
        base.CornerRadius = 0;
    }

    public new CornerRadius CornerRadius
    {
        get => (CornerRadius)GetValue(CornerRadiusProperty);
        set => SetValue(CornerRadiusProperty, value);
    }

}

create CustomFrameRender in Android.

using FrameRenderer = Xamarin.Forms.Platform.Android.AppCompat.FrameRenderer;

[assembly: ExportRenderer(typeof(CustomFrame), typeof(CustomFrameRenderer))]
namespace Demo1.Droid
{
class CustomFrameRenderer : FrameRenderer
 {
public CustomFrameRenderer(Context context)
    : base(context)
{
}

protected override void OnElementChanged(ElementChangedEventArgs<Frame> e)
{
    base.OnElementChanged(e);

    if (e.NewElement != null && Control != null)
    {
        UpdateCornerRadius();
    }
}

protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs e)
{
    base.OnElementPropertyChanged(sender, e);

    if (e.PropertyName == nameof(CustomFrame.CornerRadius) ||
        e.PropertyName == nameof(CustomFrame))
    {
        UpdateCornerRadius();
    }
}

private void UpdateCornerRadius()
{
    if (Control.Background is GradientDrawable backgroundGradient)
    {
        var cornerRadius = (Element as CustomFrame)?.CornerRadius;
        if (!cornerRadius.HasValue)
        {
            return;
        }

        var topLeftCorner = Context.ToPixels(cornerRadius.Value.TopLeft);
        var topRightCorner = Context.ToPixels(cornerRadius.Value.TopRight);
        var bottomLeftCorner = Context.ToPixels(cornerRadius.Value.BottomLeft);
        var bottomRightCorner = Context.ToPixels(cornerRadius.Value.BottomRight);

        var cornerRadii = new[]
        {
            topLeftCorner,
            topLeftCorner,

            topRightCorner,
            topRightCorner,

            bottomRightCorner,
            bottomRightCorner,

            bottomLeftCorner,
            bottomLeftCorner,
        };

        backgroundGradient.SetCornerRadii(cornerRadii);
    }
}

  }
 }

3.using custonframe in forms.

<StackLayout>
        <controls:CustomFrame
            BackgroundColor="Red"
            CornerRadius="0,30,0,0"
            HeightRequest="100"
            HorizontalOptions="Center"
            VerticalOptions="Center"
            WidthRequest="100" />
    </StackLayout>

More detailed info about this, please refer to:

https://progrunning.net/customizing-corner-radius/

Solution 2:^[2]

The easy way is to use the Nuget PancakeView.

You can specify the CornerRadius in each vertice, achieving the desired effect:

Example:

<yummy:PancakeView BackgroundColor="Orange"CornerRadius="60,0,0,60"/>

You can read more in the official page.

Solution 3:^[3]

Use the nuget package Xamarin.Forms.PancakeView.

Look at this answer for a similar question:

https://stackoverflow.com/a/59650125/5869384

Solution 4:^[4]

This is for UWP renderer

I've used the solutions from Cherry Bu - MSFT and changed it for UWP. In my project im using it in Android, iOS and UWP and it is working fine.

using System.ComponentModel;
using Windows.UI.Xaml.Media;
using Xamarin.Forms;
using Xamarin.Forms.Platform.UWP;

[assembly: ExportRenderer(typeof(CustomFrame), typeof(yourNamespace.UWP.CustomFrameRenderer))]
namespace yourNamespace.UWP
{
    public class CustomFrameRenderer : FrameRenderer
    {
        protected override void OnElementChanged(ElementChangedEventArgs<Frame> e)
        {
            base.OnElementChanged(e);

            if (e.NewElement != null && Control != null)
            {
                UpdateCornerRadius();
            }
        }

        protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs e)
        {
            base.OnElementPropertyChanged(sender, e);

            if (e.PropertyName == nameof(CustomFrame.CornerRadius) ||
                e.PropertyName == nameof(CustomFrame))
            {
                UpdateCornerRadius();
            }
        }

        private void UpdateCornerRadius()
        {
            var radius = ((CustomFrame)this.Element).CornerRadius;
            Control.CornerRadius = new Windows.UI.Xaml.CornerRadius(radius.TopLeft, radius.TopRight, radius.BottomRight, radius.BottomLeft);
        }
    }
}

Solution 5:^[5]

simple solution i have used is to set another frame behind the rounded frame something like this

<Grid>
    <Grid.RowDefinitions>
        <RowDefinition Height="0.05*"/>
        <RowDefinition Height="0.05*"/>
        <RowDefinition Height="0.8*"/>
        <RowDefinition Height="0.05*"/>
        <RowDefinition Height="0.05*"/>
    </Grid.RowDefinitions>


    <Frame
        Grid.Row="4"
        Padding="0"
        BackgroundColor="Green"
        CornerRadius="0"/>
    
    <Frame
        Grid.Row="3"
        Grid.RowSpan="2"
        Padding="0"
        BackgroundColor="Green"
        HasShadow="True"
        CornerRadius="20">
    </Frame>

</Grid>

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution	Source
Solution 1	Cherry Bu - MSFT
Solution 2	Bruno Caceiro
Solution 3	David Jesus
Solution 4	xiawi
Solution 5	???? ??? ??????

'Xamarin Frame only have a single rounded corner

Solution 1:[1]

Solution 2:[2]

Solution 3:[3]

Solution 4:[4]