xamarin-forms-tab-badge

Xamarin Forms bindable tab badges for iOS and Android. The plugin creates a custom renderer (iOS & Android) and a custom attached property for adding tab bar badges which can be bound in XF shared code.

Sample

Support & Limitations

Feature / Availability	Xamarin.Android	Xamarin.iOS
Bindable Badge Text	✓*	✓ (iOS >=8.0)
Bindable Badge Color	✓*	✓ (iOS >= 10.0)
Dynamic tab add/removal	✓*	On overflow, 'More' / '...' menu don't have badges...yet.

*Caution: For Xamarin.Forms Android make sure to use AppCompat. I.e.inherit from FormsAppCompatActivity

Installation

• Make sure to install the package in your Xamarin.Forms PCL, iOS and Android project.

// stable
Install-Package Plugin.Badge
// or pre-release
Install-Package Plugin.Badge -Pre


iOS

You have to register the custom renderer. I usually put this in the AssemblyInfo.cs file of my iOS csproj.

[assembly: ExportRenderer(typeof(TabbedPage), typeof(BadgedTabbedPageRenderer))]

Android

You have to register the custom renderer. I usually put this in the AssemblyInfo.cs file of my Android csproj.

[assembly: ExportRenderer(typeof(TabbedPage), typeof(BadgedTabbedPageRenderer))]

UWP

You have to register the custom renderer. I usually put this in the AssemblyInfo.cs file of my UWP csproj.

[assembly: ExportRenderer(typeof(TabbedPage), typeof(BadgedTabbedPageRenderer))]

Caution - Custom TabbedPage / Custom Renderers

If you are using a custom renderer for TabbedPage please change it to inherit from BadgedTabbedPageRenderer and you are all set. Of course dont forget to register your own renderer.

Linker

As you already know when you enable linkling for your application the likner might remove some of the methods/types/proeprties/events used by third party libraries. This is why it's necessary to update your LinkerPleaseInclude.cs. Check this blogpost for more linker info.

• For iOS add the following lines:

public void Include(UITabBarItem item)
{
    item.BadgeColor = UIColor.Red;
    item.BadgeValue = "badge";
}

• For Android no issues detected yet :). Feel free to report any issues here.

Usage

Badge Text

For each child page of the TabbedPage just bind the custom attached property [TabBadge.BadgeText (XAML) or TabBadge.BadgeTextPropery (CSharp)]

XAML

The important line here is binding the attached property:

  plugin:TabBadge.BadgeText="{Binding Count}"

Example tabbed page with badged children:

<TabbedPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:plugin="clr-namespace:Plugin.Badge.Abstractions;assembly=Plugin.Badge.Abstractions" 
             x:Class="Plugin.Badge.Sample.TabXaml">
  <TabbedPage.Children>
    <ContentPage Title="Tab1" 
                 Icon="icontab1.png"
                 plugin:TabBadge.BadgeText="{Binding Count}">
      <StackLayout>...</StackLayout>
    </ContentPage>
    ...
  </TabbedPage.Children>
</TabbedPage>

CSharp codebehind

var tab1 = new ContentPage //assume this is a child page of your Tab
{
    Title = "Tab1",
    Content = tab1Layout
};

tab1.SetBinding(TabBadge.BadgeTextProperty, new Binding("Count"));

Badge Color

Very similar to BadgeText just use [TabBadge.BadgeColor (XAML) or TabBadge.BadgeColorPropery (CSharp)].

Showning / Hiding the badge

If the value of the BadgeText is set to null or empty string the badge is hidden. To show it again set a non null or empty value

Licence

MIT