Android - Uso de Viewgroup

public static class FragmentoEjemplo extends Fragment {

    @Override

    public View onCreateView(LayoutInflater inflater, ViewGroup container,

                             Bundle savedInstanceState) {

        // Inflate the layout for this fragment

        return inflater.inflate(R.layout.fragmento_ejemplo, container, false);

    }

}

<com.example.android.apis.view.CustomLayout

        xmlns:android="http://schemas.android.com/apk/res/android"

        xmlns:app="http://schemas.android.com/apk/res/com.example.android.apis"

        android:layout_width="match_parent"

        android:layout_height="match_parent">

    <!-- put first view to left. -->

    <TextView

            android:background="@drawable/filled_box"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            app:layout_position="left"

            android:layout_gravity="fill_vertical|center_horizontal"

            android:text="l1"/>

    <!-- stack second view to left. -->

    <TextView

            android:background="@drawable/filled_box"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            app:layout_position="left"

            android:layout_gravity="fill_vertical|center_horizontal"

            android:text="l2"/>

    <!-- also put a view on the right. -->

    <TextView

            android:background="@drawable/filled_box"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            app:layout_position="right"

            android:layout_gravity="fill_vertical|center_horizontal"

            android:text="r1"/>

    <!-- by default views go in the middle; use fill vertical gravity -->

    <TextView

            android:background="@drawable/green"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_gravity="fill_vertical|center_horizontal"

            android:text="fill-vert"/>

    <!-- by default views go in the middle; use fill horizontal gravity -->

    <TextView

            android:background="@drawable/green"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_gravity="center_vertical|fill_horizontal"

            android:text="fill-horiz"/>

    <!-- by default views go in the middle; use top-left gravity -->

    <TextView

            android:background="@drawable/blue"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_gravity="top|left"

            android:text="top-left"/>

    <!-- by default views go in the middle; use center gravity -->

    <TextView

            android:background="@drawable/blue"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_gravity="center"

            android:text="center"/>

    <!-- by default views go in the middle; use bottom-right -->

    <TextView

            android:background="@drawable/blue"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_gravity="bottom|right"

            android:text="bottom-right"/>

</com.example.android.apis.view.CustomLayout>

@Override

    protected boolean checkLayoutParams(ViewGroup.LayoutParams p) {

        return p instanceof LayoutParams;

    }

public static class LayoutParams extends MarginLayoutParams {

        public int gravity = Gravity.TOP | Gravity.START;

        public static int POSITION_MIDDLE = 0;

        public static int POSITION_LEFT = 1;

        public static int POSITION_RIGHT = 2;

        public int position = POSITION_MIDDLE;

        public LayoutParams(Context c, AttributeSet attrs) {

            super(c, attrs);

            TypedArray a = c.obtainStyledAttributes(attrs, R.styleable.CustomLayoutLP);

            gravity = a.getInt(R.styleable.CustomLayoutLP_android_layout_gravity, gravity);

            position = a.getInt(R.styleable.CustomLayoutLP_layout_position, position);

            a.recycle();

        }

        public LayoutParams(int width, int height) {

            super(width, height);

        }

        public LayoutParams(ViewGroup.LayoutParams source) {

            super(source);

        }

    }

@Override

    public View onCreateView(LayoutInflater inflater, ViewGroup container,

                             Bundle savedInstanceState) {

        // Inflate the layout for this fragment

        return inflater.inflate(R.layout.fragmento_ejemplo, container, false);

    }

}