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How can I make an Android splash screen with text & background color that changes if my phone is in light or dark mode?

I have been working on this for some time and unfortunately I've not been able to achieve the desired effect without using an image. I have researched on Stack Overflow and almost everywhere and still found no solution that does exactly this.

What I am still trying to do is this:

  • Phone is in light mode > Splash screen has a white background with the word ABC in black in the center

  • Phone is in dark mode > Splash screen has a black background with the word ABC in white in the center

Here is what I have so far:

SplashActivity.cs

namespace Japanese.Droid
{
    [Activity(Label = "Anki+", Theme = "@style/LaunchTheme", MainLauncher = true, NoHistory = true)]
    public class SplashActivity : Activity
    {

styles.xaml

<style name="LaunchTheme" parent="Theme.AppCompat">
    <item name="android:windowBackground">@drawable/splash_screen</item>
    <item name="android:navigationBarColor">#ffffff</item>
</style>

splash_screen.xaml

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@android:color/white"/>
    <item>
        <bitmap android:src="@drawable/splash_logo"
                android:tileMode="disabled"
                android:gravity="center"
                android:layout_gravity="center"/>
    </item>
</layer-list>

splash_screen_night.xaml

<?xml version="1.0" encoding="UTF-8" ?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@android:color/black"/>
    <item>
        <bitmap android:src="@drawable/splash_logo"
                android:tileMode="disabled"
                android:gravity="center"
                android:layout_gravity="center"/>
    </item>
</layer-list>

splash_activity

using Android.App;
using Android.Content;
using Android.OS;
using Android.Runtime;
using Android.Support.V7.App;
using Android.Views;

namespace Test.Droid
{
    [Activity(Label = "Test+", Theme = "@style/LaunchTheme", MainLauncher = true, NoHistory = true)]
    public class SplashActivity : Activity
    {

        public override void OnCreate(Bundle savedInstanceState, PersistableBundle persistentState)
        {
            base.OnCreate(savedInstanceState, persistentState);

            //==================================== Code to hide the bottom 3 buttons on Android.
            int uiOptions = (int)Window.DecorView.SystemUiVisibility;
            uiOptions |= (int)SystemUiFlags.LowProfile;
            uiOptions |= (int)SystemUiFlags.Fullscreen;
            uiOptions |= (int)SystemUiFlags.HideNavigation;
            uiOptions |= (int)SystemUiFlags.ImmersiveSticky;
            Window.DecorView.SystemUiVisibility = (StatusBarVisibility)uiOptions;
            //===================================

            base.SetTheme(Resource.Style.MainTheme);
            Xamarin.Essentials.Platform.Init(this, savedInstanceState);
        }

        // Launches the startup task
        protected override void OnResume()
        {
            base.OnResume();

            //==================================== Code to hide the bottom 3 buttons on Android.
            int uiOptions = (int)Window.DecorView.SystemUiVisibility;
            uiOptions |= (int)SystemUiFlags.LowProfile;
            uiOptions |= (int)SystemUiFlags.Fullscreen;
            uiOptions |= (int)SystemUiFlags.HideNavigation;
            uiOptions |= (int)SystemUiFlags.ImmersiveSticky;
            Window.DecorView.SystemUiVisibility = (StatusBarVisibility)uiOptions;
            //===================================

            System.Threading.Tasks.Task startupWork = new System.Threading.Tasks.Task(() => { SimulateStartup(); });
            startupWork.Start();
        }


        // Simulates background work that happens behind the splash screen
        async void SimulateStartup()
        {
            await System.Threading.Tasks.Task.Delay(1000); // Simulate a bit of startup work.
            StartActivity(new Intent(Application.Context, typeof(MainActivity)));
        }

        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);
        }

        public override void OnBackPressed() { }
    }
}

This uses an image but I would like to do it with text.

Does anyone know of a way to do it. I've researched this as much as possible, asked for help from two Android devs but still nobody can come up with a simple solution to do this without using an image.

Is it possible to do this with text only and not an image for my Xamarin Android application?

Solution

  • To echieve this you need to make a SplashScreen.xml in the Layout folder in Android Project. Also you need to make the styles in two folders, values and values-night.

    Also you need a separate SplashActivity.cs. I am attaching the code herewith.

    1. SplashScreen.xml

        <?xml version="1.0" encoding="utf-8"?>
  <RelativeLayout 
   xmlns:android="http://schemas.android.com/apk/res/android"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:gravity="center_vertical" 
   android:background="#fff"
   android:id="@+id/splashview">
   <TextView
        android:id="@+id/txtAppVersion"
        android:text="Anki+"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_marginLeft="30dp"
        android:layout_marginBottom="30dp"
        android:textColor="#000"
        android:textSize="24sp"
        android:gravity="center_vertical" 
        android:layout_centerHorizontal="true"/>
    </RelativeLayout>

    2. Styles.xml in values folder.

      <style name="MainTheme" parent="MainTheme.Base">
    <item name="android:textAllCaps">false</item>
</style>

<style name="MainTheme.Base" parent="Theme.AppCompat.Light.DarkActionBar">
    <item name="windowNoTitle">true</item>
    <item name="windowActionBar">false</item>
    <item name="windowActionModeOverlay">true</item>
    <item name="elevation">0dp</item>
</style>

<style name="LaunchTheme" parent="Theme.AppCompat">
    <item name="android:windowNoTitle">true</item>
    <item name="android:windowActionBar">false</item>
    <item name="android:windowFullscreen">true</item>
    <item name="android:windowContentOverlay">@null</item>
    <item name="android:windowDisablePreview">true</item>
</style>

    3. Styles.xml in values-night folder.

      <style name="MainTheme" parent="MainTheme.Base">
    <item name="android:textAllCaps">false</item>
</style>

<style name="MainTheme.Base" parent="Theme.AppCompat.Light.DarkActionBar">
    <item name="windowNoTitle">true</item>
    <item name="windowActionBar">false</item>
    <item name="windowActionModeOverlay">true</item>
    <item name="elevation">0dp</item>
</style>

<style name="LaunchTheme" parent="Theme.AppCompat">
    <item name="android:windowNoTitle">true</item>
    <item name="android:windowActionBar">false</item>
    <item name="android:windowFullscreen">true</item>
    <item name="android:windowContentOverlay">@null</item>
    <item name="android:windowDisablePreview">true</item>
</style>

    4. SplashActivity.cs

      using System;
using Android.App;
using Android.Content;
using Android.Content.Res;
using Android.OS;
using Android.Runtime;
using Android.Views;
using Android.Widget;
using Plugin.CurrentActivity;

namespace MyProject.Droid
{
    [Activity(Label = "MyProject+", Theme = "@style/LaunchTheme", 
MainLauncher = true, NoHistory = true)]
public class SplashActivity : Activity
{

    public override void OnCreate(Bundle savedInstanceState, PersistableBundle persistentState)
    {
        base.OnCreate(savedInstanceState, persistentState);

        //==================================== Code to hide the bottom 3 buttons on Android.
        int uiOptions = (int)Window.DecorView.SystemUiVisibility;
        uiOptions |= (int)SystemUiFlags.LowProfile;
        uiOptions |= (int)SystemUiFlags.Fullscreen;
        uiOptions |= (int)SystemUiFlags.HideNavigation;
        uiOptions |= (int)SystemUiFlags.ImmersiveSticky;
        Window.DecorView.SystemUiVisibility = (StatusBarVisibility)uiOptions;
        //===================================

        base.SetTheme(Resource.Style.MainTheme);
        Xamarin.Essentials.Platform.Init(this, savedInstanceState);
    }

    // Launches the startup task
    protected override void OnResume()
    {
        base.OnResume();
        SetContentView(Resource.Layout.SplashScreen);
        bool isDarkTheme;

        //var isDarkTheme = Preferences.Get("isDarkTheme", false);
        if (Build.VERSION.SdkInt >= BuildVersionCodes.Froyo)
        {
            var uiModeFlags = CrossCurrentActivity.Current.AppContext.Resources.Configuration.UiMode & UiMode.NightMask;
            if (uiModeFlags == UiMode.NightYes)
                isDarkTheme = true;
            else isDarkTheme = false;
        }
        else
            isDarkTheme = false;

        if (isDarkTheme)
        {
            FindViewById<RelativeLayout>(Resource.Id.splashview).SetBackgroundColor(Android.Graphics.Color.ParseColor("#000000"));
            FindViewById<TextView>(Resource.Id.txtAppVersion).SetTextColor(Android.Graphics.Color.ParseColor("#FFFFFF"));
        }
        else
        {
            FindViewById<RelativeLayout>(Resource.Id.splashview).SetBackgroundColor(Android.Graphics.Color.ParseColor("#FFFFFF"));
            FindViewById<TextView>(Resource.Id.txtAppVersion).SetTextColor(Android.Graphics.Color.ParseColor("#000000"));
        }

        // FindViewById<TextView>(Resource.Id.txtAppVersion).Text = $"Version {PackageManager.GetPackageInfo(PackageName, 0).VersionName}";

        //==================================== Code to hide the bottom 3 buttons on Android.
        int uiOptions = (int)Window.DecorView.SystemUiVisibility;
        uiOptions |= (int)SystemUiFlags.LowProfile;
        uiOptions |= (int)SystemUiFlags.Fullscreen;
        uiOptions |= (int)SystemUiFlags.HideNavigation;
        uiOptions |= (int)SystemUiFlags.ImmersiveSticky;
        Window.DecorView.SystemUiVisibility = (StatusBarVisibility)uiOptions;
        //===================================

        System.Threading.Tasks.Task startupWork = new System.Threading.Tasks.Task(() => { SimulateStartup(); });
        startupWork.Start();
    }

    // Simulates background work that happens behind the splash screen
    async void SimulateStartup()
    {
        await System.Threading.Tasks.Task.Delay(1000); // Simulate a bit of startup work.
        StartActivity(new Intent(Application.Context, typeof(MainActivity)));
    }

    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);
    }

    public override void OnBackPressed() { }
}
}