Looks for 0dp as the width in a vertical LinearLayout or as the height in a horizontal
Using 0dp as the width in a horizontal LinearLayout with weights is a useful trick to ensure that only the weights (and not the intrinsic sizes) are used when sizing the children.
However, if you use 0dp for the opposite dimension, the view will be invisible. This can happen if you change the orientation of a layout without also flipping the 0dp dimension in all the children.