//MainActivity.java

import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
}

//splashscreen.java

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;

public class splashscreen extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.splashscreen);

        //Splash Screen duration
        int secondsDelayed = 1;
        new Handler().postDelayed(new Runnable() {
            public void run() {
                startActivity(new Intent(splashscreen.this, MainActivity.class));
                finish();
            }
        }, secondsDelayed * 3000);
    }
}

//activity_main.xml




    



//splashscreen.xml



      
Source: https://github.com/Lunox-Code/SplashScreen