android studio how do center layout in the screen on tablet devices

Your layout is not centering on tablet because the main content container is using match_parent width. When a view fills the entire width of its parent, there is nothing left to center, so it appears stuck to the top left.

Also, layout_centerInParent does not work inside ConstraintLayout. That attribute only applies to RelativeLayout.

The correct approach in ConstraintLayout is to wrap all of your content inside a single container and constrain that container to all four sides of the parent. Then give it a maximum width so it does not stretch across the whole tablet screen.

Here is the corrected structure:

<?xml version="1.0" encoding="utf-8"?> <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:layout_width="match_parent" android:layout_height="match_parent" tools:context=".Settings"> <LinearLayout android:id="@+id/centerContainer" android:layout_width="0dp" android:layout_height="wrap_content" android:orientation="vertical" android:padding="24dp" android:maxWidth="700dp" app:layout_constraintTop_toTopOf="parent" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent"> <TextView android:id="@+id/app_name" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="MouseForCat" android:textSize="40sp" android:layout_gravity="center" android:layout_marginBottom="20dp"/> <TextView android:id="@+id/Settings" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Settings" android:textSize="32sp" android:layout_marginTop="20dp" android:layout_marginBottom="20dp"/> <LinearLayout android:id="@+id/SettingsLayout" android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="vertical" android:background="@drawable/settings_background" android:padding="16dp"> <!-- Keep your existing setting rows here --> </LinearLayout> <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="horizontal" android:gravity="center" android:layout_marginTop="30dp"> <Button android:id="@+id/SaveBtn" android:layout_width="120dp" android:layout_height="wrap_content" android:text="Save"/> <Button android:id="@+id/CancelBtn" android:layout_width="120dp" android:layout_height="wrap_content" android:text="Cancel" android:layout_marginStart="20dp"/> <Button android:id="@+id/PlayBtn" android:layout_width="120dp" android:layout_height="wrap_content" android:text="Play" android:layout_marginStart="20dp"/> </LinearLayout> </LinearLayout> </androidx.constraintlayout.widget.ConstraintLayout>

The important parts are layout_width set to 0dp on the centered container and constraints applied to top, bottom, start, and end of the parent. The maxWidth prevents the layout from stretching across large tablet screens.

This keeps the layout natural on phones and centered on tablets without needing a separate sw600dp layout.

Hope this helps