Stretch to fill VideoView, aspect ratio of VideoView

video view should be inside to the Relative Layout. Here is an example given below. In my case, it works very fine with a FullScreen Button.

<RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="3"
            android:id="@+id/videoVIewLinId"
            android:layout_gravity="center"
            android:gravity="center"
            android:scaleType="fitXY"

            >
                <VideoView
                    android:layout_alignParentTop="true"
                    android:layout_alignParentBottom="true"
                    android:layout_alignParentLeft="true"
                    android:layout_alignParentRight="true"
                    android:layout_alignParentEnd="true"
                    android:layout_alignParentStart="true"
                    android:layout_width="fill_parent"
                    android:layout_height="fill_parent"
                    android:id="@+id/videoViewId"
                    />


                <ImageView
                    android:id="@+id/fullScreenBtnIdOnlineMedia"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:src="@drawable/ic_action_full_screen"
                    android:layout_alignParentEnd="true"
                    android:layout_alignParentBottom="true"
                    android:layout_marginEnd="10dp"

                    />

        </RelativeLayout>

Try to make your outer layout a relative layout and put the VideoView inside that.

Something like:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:id="@+id/trim_container"
     android:layout_width="match_parent"
     android:layout_height="match_parent" >

     <LinearLayout
          android:id="@+id/buttonContainer"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:orientation="horizontal" >

     <Button
          android:id="@+id/go_back"
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:layout_gravity="center"  
          android:layout_weight="1"
          android:onClick="onclick"
          android:text="Try again" />

     <Button
          android:id="@+id/back_to_pick_song"
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:layout_weight="1"
          android:text="Select another song" 
          android:onClick="onclick" />

    <Button
          android:id="@+id/btn_continue"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:layout_gravity="center"
          android:layout_weight="1"
          android:onClick="onclick"
          android:text="Amazing, continue!" />
  </LinearLayout>

  <VideoView
     android:id="@+id/VideoView"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:layout_alignParentLeft="true"
     android:layout_alignParentRight="true"
     android:layout_alignParentBottom="true"
     android:layout_below="@id/buttonContainer"/>
</RelativeLayout>