在约束布局中设置视频观看位置

Question

main_acitivity.xml

<?xml version="1.0" encoding="utf-8"?>
<!--suppress ALL -->
<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"
android:background="@color/black"
android:id="@+id/main"
tools:context=".MainActivity"
android:layout_gravity="center"
android:gravity="center"
>

<VideoView
    android:id="@+id/videoView1"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:layout_centerInParent="true"
    android:layout_gravity="center"
    android:gravity="center"
    />
</androidx.constraintlayout.widget.ConstraintLayout>

然后在java中，我继续下一个

vv = (VideoView)     
findViewById(R.id.videoView1);

    ConstraintLayout.LayoutParams pararams = (ConstraintLayout.LayoutParams) vv.getLayoutParams();
    int ch=vv.getHeight();
    pararams.height = vv.getWidth();


    vv.setLayoutParams(pararams);

随后如何使元素垂直居中？我做了vv.setY，我做了页边空白，我尝试用xml做东西-没用，视频在顶部或延伸到所有窗口

Answer 1