Custom Renderer not working anymore when tabs are navigation pages

[jaspervanmegroot]

Custom Renderer for TabbedPage is not working anymore (Android). layout.TabCount stays 0. How the fix this?

Version Xamarin: latest
Version plugin: latest

[assembly: ExportRenderer(typeof(MainPage), typeof(MyTabbedPageRenderer))]
public class MyTabbedPageRenderer : BadgedTabbedPageRenderer
    {
        private ViewPager viewPager;
        private MainPage page;
        private Activity activity;
        private bool setup;
        private TabLayout layout;

        public MyTabbedPageRenderer(Context context) : base(context) { }

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

            if (setup)
                return;

            if (e.PropertyName == "Renderer")
            {
                viewPager = (ViewPager)ViewGroup.GetChildAt(0);
                layout = (TabLayout)ViewGroup.GetChildAt(1);
                setup = true;

                ColorStateList colors = Resources.GetColorStateList(Resource.Color.icon_tab, Context.Theme);

                for (int i = 0; i < layout.TabCount; i++)
                {
                    var tab = layout.GetTabAt(i);
                    var icon = tab.Icon;
                    if (icon != null)
                    {
                        icon = Android.Support.V4.Graphics.Drawable.DrawableCompat.Wrap(icon);
                        Android.Support.V4.Graphics.Drawable.DrawableCompat.SetTintList(icon, colors);
                    }
                }
            }
        }

        protected override void OnElementChanged(ElementChangedEventArgs<TabbedPage> e)
        {
            base.OnElementChanged(e);
            activity = this.Context as Activity;

            TabLayout layout = null;
            page = (MainPage)e.NewElement;

            for (int i = 0; i < ChildCount; i++)
            {
                var v = GetChildAt(i);
                if (v is ViewPager)
                    viewPager = (ViewPager)v;
                else if (v is TabLayout)
                    layout = (TabLayout)v;
            }
            if (layout != null)
            {
                for (int tabIndex = 0; tabIndex < layout.TabCount; tabIndex++)
                    SetTabIcon(layout, tabIndex);
            }

            try
            {
                viewPager.SetPageTransformer(false, new NoAnimationPageTransformer());
            }
            catch (Exception ex)
            {
                Utils.LogError(DateTime.Now + " - " + ex.Message + " " + ex.StackTrace);
            }
        }

        private void SetTabIcon(TabLayout layout, int tabIndex)
        {
            var tab = layout.GetTabAt(tabIndex);
            tab.SetText("");

            switch (tabIndex)
            {
                case 0:
                    tab.SetIcon(Resource.Drawable.dashboard_icon);
                    break;
                case 1:
                    tab.SetIcon(Resource.Drawable.gesprekken_icon);
                    break;
                case 2:
                    tab.SetIcon(Resource.Drawable.info_icon);
                    break;
                case 3:
                    tab.SetIcon(Resource.Drawable.instellingen_icon);
                    break;
            }
        }
    }
}

MainPage:

public partial class MainPage : Xamarin.Forms.TabbedPage
    {
        public static readonly BindableProperty TabBarHiddenProperty = BindableProperty.Create("TabBarHidden", typeof(bool), typeof(MainPage), false);

        public static int DashboardPage = 0;
        public static int GesprekkenPage = 1;
        public static int InfoPage = 2;
        public static int SettingsPage = 3;
        public static int TimelinePage = -1;

        public bool TabBarHidden
        {
            get { return (bool)GetValue(TabBarHiddenProperty); }
            set { SetValue(TabBarHiddenProperty, value); }
        }

        public MainPage()
        {
            Device.BeginInvokeOnMainThread(() =>
            {
                SetMainPage();
            });
        }

        public MainPage(int page)
        {
            Device.BeginInvokeOnMainThread(() =>
            {
                SetMainPage();
                SetCurrentPage(page);
            });
        }

        private void SetMainPage()
        {
            InitializeComponent();

            try
            {
                CreateNavigationPage(new DashboardPage(), "Dashboard", "dashboard_icon");
                CreateNavigationPage(new ContactPage(), "Gesprekken", "gesprekken_icon");
                CreateNavigationPage(new InfoPage(), "Informatie", "info_icon");
                CreateNavigationPage(new SettingsPage(), "Instellingen", "instellingen_icon");

                MessagingCenter.Subscribe<ContactPage, int>(this, "badgeCount", (sender, count) =>
                {
                    SetBadge(count);
                });
            }
            catch (Exception ex)
            {
                Utils.LogError(DateTime.Now + ": " + ex.Message + " - " + ex.StackTrace);
            }

            BarBackgroundColor = (Color)App.Current.Resources["backgroundNavigationBar"];
            BarTextColor = Color.White;
        }

        private void CreateNavigationPage(object objectType, string title, string icon)
        {
            var navigationPage = new FontNavigationPage((Page)objectType);
            navigationPage.Icon = icon;
            navigationPage.Title = title;
            navigationPage.BarBackgroundColor = (Color)App.Current.Resources["backgroundNavigationBar"];
            navigationPage.BarTextColor = Color.White;
            Children.Add(navigationPage);
        }

        public void SetBadge(int count)
        {
            if (Children.Count < 4)
                return;

            if (count == 0)
                TabBadge.SetBadgeText(Children[1], "");
            else
            {
                TabBadge.SetBadgeText(Children[1], count.ToString());
                TabBadge.SetBadgeColor(Children[1], Color.Red);
            }
        }

        public void SetCurrentPage(int page)
        {
            this.CurrentPage = Children[page];
        }

        public void OpenChatPage(ChatPage chatPage)
        {
            this.CurrentPage.Title = "";
            this.CurrentPage.Navigation.PushAsync(chatPage);
        }
    }

[xabre]

@jaspervanmegroot could it be related to #43?

[jaspervanmegroot]

Where do I need to set a delay?

[Axemasta]

@xabre I'm having an issue with badges not being shown and this issue happens regardless of whether there is a previous screen (like in #43). I can however access the badge text of the view, and it spits out the correct number (according to the binding).

[xabre]

This seems to be caused by the same issue as #46.

[xabre]

Check

Pre-release with XF 3.1 android bottom tab placement suport is out:

https://www.nuget.org/packages/Plugin.Badge/2.1.0-pre.2

Please give it a try and let me know if you spot some problems.