Android Button button center

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center"
    tools:context="com.example.xuhao.tongzhiapplication.MainActivity"
    android:weightSum="1">
    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center" />
</LinearLayout>

You can't just write Android:layout_gravity="center" in the Button attribute here, because this can only mean centering in the direction of the parent container, so you need to add it to the parent container LinearLayout

android:gravity="center"

Button centering effect can be achieved