Buatlah Activity Baru dengan nama Splash_Screen, kemudian buatlah layout untuk activity splash_screen nya, misalnya menambahkan sebuah gambar dan progressbar

package giviews.id.splash;



import android.content.Intent;

import android.os.Bundle;

import android.support.v7.app.AppCompatActivity;



import static android.view.Window.FEATURE_NO_TITLE;



public class Splash_Screen extends AppCompatActivity {



    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        this.requestWindowFeature(FEATURE_NO_TITLE);

        setContentView(R.layout.activity_splash__screen);

    Thread myThread = new Thread() {

        @Override

        public void run() {

            try {

                sleep(3000);

                Intent intent = new Intent(getApplicationContext(),MainActivity.class);

                startActivity(intent);

                finish();

            } catch (InterruptedException e) {

                e.printStackTrace();

            }

        }

    };

        myThread.start();

    }

}

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

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    package="giviews.id.splash">



    <application

        android:allowBackup="true"

        android:icon="@mipmap/ic_launcher"

        android:label="@string/app_name"

        android:roundIcon="@mipmap/ic_launcher_round"

        android:supportsRtl="true"

        android:theme="@style/AppTheme">

        <activity android:name=".Splash_Screen">

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />



                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

        <activity

            android:name=".MainActivity"

            android:theme="@style/Base.V7.Theme.AppCompat"

            tools:ignore="DuplicateActivity">

            <meta-data

                android:name="android.support.PARENT_ACTIVITY"

                android:value="giviews.id.splash.MainActivity" />

        </activity>



    </application>



</manifest>