center categories tab layout on android

src/Dollet.Presentation/Maui/MauiProgram.cs

@@ -5,6 +5,9 @@
 using Microcharts.Maui;
 using Microsoft.Extensions.Configuration;
 using System.Reflection;
+#if ANDROID
+using Dollet.Platforms.Android.Renderers;
+#endif
 
 namespace Dollet
 {
@@ -21,8 +24,13 @@ public static MauiApp CreateMauiApp()
                     fonts.AddFont("MaterialIcons-Regular.ttf", "MaterialIconsRegular");
                 })
                 .UseMicrocharts()
-                .UseMauiCommunityToolkit();
-
+                .UseMauiCommunityToolkit()
+                .ConfigureMauiHandlers(handlers =>
+                {
+#if ANDROID
+                    handlers.AddHandler(typeof(Shell), typeof(CustomShellRenderer));
+#endif
+                });
 
             FormHandler.RemoveBorders();
 

src/Dollet.Presentation/Maui/Platforms/Android/Renderers/CustomShellRenderer.cs

@@ -0,0 +1,15 @@
+using Android.Content;
+using Dollet.Platforms.Android.Trackers;
+using Microsoft.Maui.Controls.Handlers.Compatibility;
+using Microsoft.Maui.Controls.Platform.Compatibility;
+
+namespace Dollet.Platforms.Android.Renderers
+{
+    public class CustomShellRenderer(Context context) : ShellRenderer(context)
+    {
+        protected override IShellTabLayoutAppearanceTracker CreateTabLayoutAppearanceTracker(ShellSection shellSection)
+        {
+            return new CustomTabLayoutAppearanceTracker(this);
+        }
+    }
+}

src/Dollet.Presentation/Maui/Platforms/Android/Trackers/CustomTabLayoutAppearanceTracker.cs

@@ -0,0 +1,16 @@
+using Google.Android.Material.Tabs;
+using Microsoft.Maui.Controls.Platform.Compatibility;
+
+namespace Dollet.Platforms.Android.Trackers
+{
+    public class CustomTabLayoutAppearanceTracker(IShellContext shellContext) : ShellTabLayoutAppearanceTracker(shellContext)
+    {
+        public override void SetAppearance(TabLayout tabLayout, ShellAppearance appearance)
+        {
+            base.SetAppearance(tabLayout, appearance);
+
+            tabLayout.TabMode = TabLayout.ModeFixed;
+            tabLayout.TabGravity = TabLayout.GravityFill;
+        }
+    }
+}