Create FirstStartupActivity

app/src/main/AndroidManifest.xml

@@ -23,6 +23,10 @@
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
+        <activity android:name=".FirstStartupActivity"
+            android:screenOrientation="portrait"
+            tools:ignore="LockedOrientationActivity">
+        </activity>
         <activity android:name=".ChooseActivity"
             android:screenOrientation="portrait"
             tools:ignore="LockedOrientationActivity">

app/src/main/java/com/finnmglas/launcher/FirstStartupActivity.kt

@@ -0,0 +1,35 @@
+package com.finnmglas.launcher
+
+import android.annotation.SuppressLint
+import android.content.Context
+import android.os.Bundle
+import android.view.*
+import androidx.appcompat.app.AppCompatActivity
+
+class FirstStartupActivity : AppCompatActivity(){
+
+    /* Overrides */
+
+    @SuppressLint("SetTextI18n") // I do not care
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+
+        val sharedPref = this.getSharedPreferences(
+            getString(R.string.preference_file_key), Context.MODE_PRIVATE)
+
+        initSettings(sharedPref, this)
+
+        // Flags
+        window.setFlags(
+            WindowManager.LayoutParams.FLAG_FULLSCREEN,
+            WindowManager.LayoutParams.FLAG_FULLSCREEN
+        )
+        window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON)
+
+        setContentView(R.layout.activity_firststartup)
+    }
+
+    fun clickAnywhere(view: View){
+        finish()
+    }
+}

app/src/main/java/com/finnmglas/launcher/MainActivity.kt

@@ -33,7 +33,7 @@ GestureDetector.OnDoubleTapListener {
     private lateinit var mDetector: GestureDetectorCompat
 
     // get device dimensions
-    val displayMetrics = DisplayMetrics()
+    private val displayMetrics = DisplayMetrics()
 
     private fun getIntent(packageName: String): Intent? {
         val pm = applicationContext.packageManager
@@ -108,7 +108,7 @@ GestureDetector.OnDoubleTapListener {
 
         // First Startup
         if (!sharedPref.getBoolean("startedBefore", false))
-            initSettings(sharedPref, this)
+            startActivity(Intent(this, FirstStartupActivity::class.java))
 
         loadSettings(sharedPref)
 

app/src/main/res/layout/activity_firststartup.xml

@@ -0,0 +1,22 @@
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/container"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:background="?attr/colorPrimaryDark"
+    android:longClickable="false"
+    android:onClick="clickAnywhere"
+    tools:context=".MainActivity">
+
+    <TextView
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:text="Hello."
+        android:textColor="#fff"
+        android:textSize="64sp"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent" />
+</androidx.constraintlayout.widget.ConstraintLayout>