Editor Width very small when empty

Hello,

I'm struggling with Editor component and have no clue on how to solve it.

I have an Editor (in fact an ExtEditor that inherits from Editor and has a Renderer). When the Text property is empty, the editor is very small. When I have some text in it it takes the width of this text. It has a style applied with HorizontalOptions set as FillAndExpand.

How could I set the width of this editor so it takes the available width of the container ?

Some code :

My view ; components:EditEntityPropertyRow is a composite component with a bunch of styles, and a label followed by whatever control I need in EditView, it works fine for every other kind of controls (Entry, DatePicker...) :

<?xml version="1.0" encoding="UTF-8"?>
<ContentPage 
    xmlns="http://xamarin.com/schemas/2014/forms" 
    xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml" 
    xmlns:sys="clr-namespace:System;assembly=mscorlib"
    xmlns:i18n="clr-namespace:Sharemat.Locales;assembly=Sharemat"
    xmlns:components="clr-namespace:Sharemat.Components;assembly=Sharemat"
    x:Class="Sharemat.Pages.Reports.ReportCreateTabs.MainTab">
    <ContentPage.Content>
        <StackLayout VerticalOptions="FillAndExpand">
            <ScrollView Padding="10, 0, 10, 0">
                <StackLayout>

                    <StackLayout BackgroundColor="White">

...

                        <components:EditEntityPropertyRow Title="{i18n:Translate Entity.Intervention.Report.Description}">
                            <components:EditEntityPropertyRow.EditView>
                                <AbsoluteLayout HeightRequest="100" HorizontalOptions="FillAndExpand">
                                    <components:ExtEditor x:Name="ReportDescriptionEditor" Text="Binding Item.ReportDescription" Style="{StaticResource EditEntityPropertyExtEditor}" />
                                    <components:MenuIcon x:Name="SpeechRecognition" IconName="speech-recognition" 
                                            HorizontalOptions="End"
                                            VerticalOptions="End"
                                            HeightRequest="60" 
                                            AbsoluteLayout.LayoutBounds="0,0,1,1" 
                                            AbsoluteLayout.LayoutFlags="All"
                                    />
                                </AbsoluteLayout>
                            </components:EditEntityPropertyRow.EditView>
                        </components:EditEntityPropertyRow>

... 

                    </StackLayout>

                </StackLayout>
            </ScrollView>
        </StackLayout>
    </ContentPage.Content>
</ContentPage>

The style for EditEntityPropertyExtEditor :

            <Style x:Key="EditEntityPropertyExtEditor" TargetType="components:ExtEditor">
                <Setter Property="HorizontalOptions" Value="FillAndExpand" />
                <Setter Property="VerticalOptions" Value="FillAndExpand" />
                <Setter Property="FontSize" Value="14" />
                <Setter Property="HeightRequest" Value="100" />
            </Style>

The renderer for ExtEditor just sets a background with rounded border :

using System;

using Android.Content;
using Android.Graphics.Drawables;

using Xamarin.Forms;
using Xamarin.Forms.Platform.Android;

using Sharemat.Components;
using Sharemat.Droid.Renderers;

[assembly: ExportRenderer(typeof(ExtEditor), typeof(ExtEditorRenderer))]
namespace Sharemat.Droid.Renderers
{
    public class ExtEditorRenderer : EditorRenderer
    {
        public ExtEditorRenderer(Context context) : base(context)
        {
        }

        protected override void OnElementChanged(ElementChangedEventArgs<Xamarin.Forms.Editor> e)
        {
            base.OnElementChanged(e);

            if (e.OldElement == null)
            {
                // Crée un drawable avec des bords arrondis
                GradientDrawable MyCornerRadiusDrawable = new GradientDrawable();
                MyCornerRadiusDrawable.SetCornerRadius(3);
                MyCornerRadiusDrawable.SetStroke(1, Xamarin.Forms.Color.Black.ToAndroid());

                // Combine les drawable
                Drawable[] DrawablesArray = { MyCornerRadiusDrawable };
                var layers = new LayerDrawable(DrawablesArray);

                // Rabougrit le padding sinon le controle prend trop ses aises
                Control.SetPadding(7, 7, 7, 7);

                // Set le background avec les drawables créés
                Control.SetBackground(layers);
            }
        }
    }
}