Xamarin Forms Android Theming: Unable to change actionBar primaryColor

Question

After this try:
https://learn.microsoft.com/en-us/answers/questions/562442/unable-to-use-custom-theme-in-android-xamarinforms.html

And after resolving this error:
https://learn.microsoft.com/en-us/answers/questions/565478/androidviewsinflateexception-binary-xml-file-line.html

I could change the statusBarColor and the navigationBarColor but not the colorPrimary of the action bar.

This is MainActivity.cs:

using Android.App;  
using Android.Content.PM;  
using Android.Runtime;  
using Android.Views;  
  
using Android.OS;  
using Xamarin.Forms.Internals;  
  
namespace Almicantarat.Droid  
{  
	[Activity (Label = "Almicantarat",   
		Icon = "@drawable/almicantarat_launcher",   
		MainLauncher = true,  
		ConfigurationChanges = ConfigChanges.ScreenSize | ConfigChanges.Orientation)]  
	//Theme = "@style/MainTheme",   
	public class MainActivity : global::Xamarin.Forms.Platform.Android.FormsAppCompatActivity  
	{  
		protected override void OnCreate (Bundle savedInstanceState)  
		{  
			base.OnCreate (savedInstanceState);  
			Xamarin.Forms.Forms.SetFlags("SwipeView_Experimental");  
			Xamarin.Essentials.Platform.Init(this, savedInstanceState);  
  
  
			Registrar.Registered.Register(typeof(Xamarin.Forms.CheckBox), typeof(Xamarin.Forms.Platform.Android.CheckBoxRenderer));  
  
			global::Xamarin.Forms.Forms.Init (this, savedInstanceState);  
			Xamarin.FormsMaps.Init(this, savedInstanceState);  
			  
            LoadApplication(new AlmicantaratXF.Views.App (AlmicantaratXF.Views.FirstPage.HomePage));  
  
        }  
		public override void OnRequestPermissionsResult(int requestCode, string[] permissions, [GeneratedEnum] Android.Content.PM.Permission[] grantResults)  
		{  
			Xamarin.Essentials.Platform.OnRequestPermissionsResult(requestCode, permissions, grantResults);  
  
			base.OnRequestPermissionsResult(requestCode, permissions, grantResults);  
		}  
	}  
}  

This is styles.xml:

<?xml version="1.0" encoding="utf-8" ?>  
<resources>  
  <style name="AlmicantaratTheme" parent="Theme.AppCompat.NoActionBar">  
      <item name="android:windowNoTitle">true</item>  
      <item name="android:windowActionBar">false</item>  
      <item name="android:colorPrimary">#15014E</item>  
      <item name="android:colorPrimaryDark">#15014E</item>  
      <item name="android:navigationBarColor">#15014E</item>  
      <item name="android:statusBarColor">#15014E</item>  
      <item name="android:colorAccent">#FF4081</item>  
      <!--<item name="android:windowActionModeOverlay">true</item>-->  
  </style>  
</resources>  

This is AndroidManifest.xml:

<?xml version="1.0" encoding="utf-8"?>  
<manifest xmlns:android="http://schemas.android.com/apk/res/android" android:installLocation="preferExternal" package="almicantarat.almicantarat" android:versionCode="17" android:versionName="1.3.0">  
	<uses-sdk android:minSdkVersion="21" android:targetSdkVersion="29" />  
	<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />  
	<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />  
	<uses-permission android:name="android.permission.INTERNET" />  
	<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />  
	<application android:label="Almicantarat"  
               android:icon="@drawable/almicantarat_launcher"  
							 android:theme="@style/AlmicantaratTheme">  
		<meta-data android:name="com.google.android.geo.API_KEY" android:value="***" />  
		<meta-data android:name="com.google.android.gms.version" android:value="@integer/google_play_services_version" />  
		<uses-library android:name="org.apache.http.legacy" android:required="false" />  
	</application>  
</manifest>  

And this is the result:

The actionBar is black instead of the primaryColor I set (#15014E)

Answer 1

I feel ashamed as I found the origin of the issue:

The toolbar was modified by NavigationPage BarBackgroundColor in App.xaml:

<?xml version="1.0" encoding="utf-8"?>  
<Application xmlns="http://xamarin.com/schemas/2014/forms"  
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"  
             x:Class="AlmicantaratXF.Views.App">  
    <Application.Resources>  
        <ResourceDictionary Source="Themes/DarkTheme.xaml">  
        <!-- The following code was setting the toolbar background color -->  
  <!--      <Style TargetType="{x:Type NavigationPage}">  
                <Setter Property="BarBackgroundColor"  
                        Value="Black" />  
                <Setter Property="BarTextColor"  
                        Value="White" />  
            </Style> -->  
   

@JarvanZhang , thank you for the time spent on this issue.

Regards,

Answer 2

Hello pierrelouisdeschamps-1678,​

Welcome to our Microsoft Q&A platform!

It's unnecessary to add 'android:' prefix for some resource properties in styles.xml. Please change the code like below:

   <style name="AlmicantaratTheme" parent="Theme.AppCompat.NoActionBar">  
     <item name="windowNoTitle">true</item>  
     <item name="windowActionBar">false</item>  
     <item name="colorPrimary">#15014E</item>  
     <item name="colorPrimaryDark">#15014E</item>  
     <item name="android:navigationBarColor">#15014E</item>  
     <item name="android:statusBarColor">#15014E</item>  
     <item name="colorAccent">#FF4081</item>  
     <item name="windowActionModeOverlay">true</item>  
   </style>  

Theme.AppCompat.NoActionBar is in dark mode, if you want to use the light mode, please change the parent to Theme.AppCompat.Light.NoActionBar.

Best Regards,

Jarvan Zhang

---

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Answer 3

Hello @JarvanZhang ,

I have changed the android:colorPrimary to colorPrimary. But the toolbar background is still black instead of #15014E.

I use this page:
https://learn.microsoft.com/en-us/xamarin/android/user-interface/material-theme

And succeeded in converting it to AndroidX but cannot change the toolbar background.

Regards,

Answer 4

The issue I am facing is connected to Theming and to Custom Toolbar.

Currently I am unable to use the default Action Bar: if I remove everything about custom toolbar in style.xml:

<?xml version="1.0" encoding="utf-8" ?>
<resources>

  <style name="AlmicantaratTheme" parent="Theme.AppCompat"> <!--parent="Theme.AppCompat.NoActionBar"-->
 <!-- <item name="windowNoTitle">true</item>
      <item name="windowActionBar">false</item> -->
      <item name="colorPrimary">#15014E</item>
      <item name="colorPrimaryDark">#15014E</item>
      <item name="android:navigationBarColor">#15014E</item>
      <item name="android:statusBarColor">#15014E</item>
      <item name="colorAccent">#3498db</item>
      <item name="android:windowActionModeOverlay">true</item>
  </style>
</resources>

and in MainActivity.cs:

            //ToolbarResource = Resource.Layout.Toolbar;
            //TabLayoutResource = Resource.Layout.Tabbar;
            //var toolbar = FindViewById<Android.Widget.Toolbar>(Resource.Id.toolbar);
            //SetActionBar(toolbar);

I get the following exception in MainActivity.cs:

Java.Lang.IllegalStateException: 'This Activity already has an action bar supplied by the window decor. Do not request Window.FEATURE_SUPPORT_ACTION_BAR and set windowActionBar to false in your theme to use a Toolbar instead.'

but If I use a Custom Toolbar, I cannot change the background...