xml activity_main.xml中

Posted 2021-05-16

<LinearLayout 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"
    android:gravity="center"
    android:orientation="vertical"
    android:fitsSystemWindows="true"
    tools:context=".MainActivity"
    >
    ...
</LinearLayout>