xamarin-forms-tab-badge

Xamarin Forms bindable tab badges for iOS, Android, UWP, MacOS and WPF. The plugin creates a custom renderer (for each platform) 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 (1)	Xamarin.iOS	UWP (2)	MacOS (3)	WPF (4)
Bindable Badge Text	✓	✓ (>=8.0)	✓	✓	✓
Bindable Badge Color	✓	✓ (>= 10.0)	✓	✓	✓
Bindable Badge Text Color	✓	✓ (>= 10.0)	✓	✓	✓
Bindable Badge Font	✓*	✓ *(>= 10.0)	✓	✓	✓
Bindable Badge Postion	✓	✕	✓	✓	✓
Bindable Badge Margin	✓	✕	✓	✓	✓
Dynamic tab add/removal	✓	No overflow	✓	✓	✓

*(1) Min Android API level 15, bottom placement also supported starting with v2.1.0

*(2) Min UWP version: Win 10 Fall Creators Update (XF.3 has a .netstandard 2 requirement).

*(3) MacOS version: -

*(4) WPF version: -

**Font restrictions: able to bind font attributes and family but not size

Installation

• Make sure to install the package in your Xamarin.Forms shared/core project as well as a platform specifc projects.

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

iOS, Android, UWP, MacOS, WPF

You have to register the custom renderer. I usually put this in the AssemblyInfo.cs file of my Platform specific project (iOS, Android, UWP, MacOS, WPF) csproj.

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

Caution: If you are using the NON AppCompat MainActivity (i.e. you Main activity inherits from FormsApplicationActivity) please register the 'Legacy' renderer

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

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 linker might remove some of the methods/types/properties/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)].

Badge Text Color

Very similar to BadgeColor just use [TabBadge.BadgeTextColor (XAML) or TabBadge.BadgeTextColorPropery (CSharp)].

Badge Font Attributes

Very similar to BadgeColor just use [TabBadge.BadgeFont (XAML) or TabBadge.BadgeFontPropery (CSharp)].

ToDo:

• you can alo try to set font family, should work in theory
• font size is not supported yet on android ......

Badge Position

Very similar to BadgeColor just use [TabBadge.BadgePosition (XAML) or TabBadge.BadgePositionPropery (CSharp)].

TopLeft	BottomLeft	BottomRight	Center	TopCenter	BottomCenter	LeftCenter	RightCenter

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

Generic Badge View

As of v2.2.0 the package also contains a XF Badge view that is based on a XF Frame View and can be added to any layout and bound using the usual approach. The generic badge view can also be added to custom NavigationPage.TitleView layouts.

Checkout the Sample-App for more.

Licence

MIT