Forum Xamarin.Android

Making larger Floating Action Button (FAB)

For my project, I need a bigger Floating Action Button (FAB) (I know it goes against principles of Google Material Design, but can't do much about that). I know that FAB has default and mini sizes to them. To get bigger size, I made custom button class that inherits FAB class:

`using System;
using Android.Content;
using Android.Content.Res;
using Android.Graphics;
using Android.Graphics.Drawables;
using Android.Runtime;
using Android.Util;
using Android.Views;
using Java.Lang;
using Android.Support.Design.Widget;

public class BiggerFloatingActionButton : FloatingActionButton
[Register(".ctor", "(Landroid/content/Context;)V", "")]
public BiggerFloatingActionButton(Context context) : base(context)
[Register(".ctor", "(Landroid/content/Context;Landroid/util/AttributeSet;)V", "")]
public BiggerFloatingActionButton(Context context, IAttributeSet attrs) : base(context, attrs) { }
[Register(".ctor", "(Landroid/content/Context;Landroid/util/AttributeSet;I)V", "")]
public BiggerFloatingActionButton(Context attrscontext, IAttributeSet attrs, int defStyleAttr) : base(attrscontext, attrs, defStyleAttr) { }
protected BiggerFloatingActionButton(IntPtr javaReference, JniHandleOwnership transfer) : base(javaReference, transfer) { }

protected override void OnMeasure(int widthMeasureSpec, int heightMeasureSpec)
    base.OnMeasure(widthMeasureSpec, heightMeasureSpec);
    int width = this.MeasuredWidth;
    int height = this.MeasuredHeight;

    this.SetMeasuredDimension((int)(width * 1.75f), (int)(height * 1.75f));
    //base.OnMeasure(width, height);


In result, it works, but there are problems on Android API 19 and probably lower:

While on Android API 20 it looks alright:"

Does anyone know the clue why the former effect happens?

Usage of my custom FAB is as follows:
var buttons = new List();
foreach (var item in categories)
var button = new BiggerFloatingActionButton(this);
var iconIdentifier = this.Resources.GetIdentifier(item.Icon, "drawable", this.ApplicationContext.PackageName);

    var drawable = ContextCompat.GetDrawable(this, iconIdentifier);


var layout = this.FindViewById<LinearLayout>(Resource.Id.linear_main);
foreach(var button in buttons)


For reference, I use the newest Xamarin for Visual Studio version.
Thank you!

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