Couldn't change the height and width of a layout

Question

In background it is listed as a constraintLayout , I am trying to insert a Linear Horizontal Layout over it. Whenever I assign match_parent to both android:layout_width and android:layout_height , it automatically reverts back to some Fixed Dp (like 395dp for width and 587dp for height) . How to change this setting?

Screenshot Here

Answer 1

Match parent won't work inside a constraint layout, you have to define the relative position inside the constraint layout. You have to assign the layout_constraintStart_toStartOf and layout_constraintEnd_toEndOf