gridSize property
How a grid size is determined.
When it is SpannableGridSize.parent, grid is sized to fully fit parent's constrains. This means that grid cell's aspect ratio will be the same as the grid's one. If it is SpannableGridSize.parentWidth or SpannableGridSize.parentHeight, then grid's height or width respectively will be equal the opposite side. Consequently, in this case grid cell's aspect ratio is 1 (grid cells are square).
Defaults to SpannableGridSize.parentWidth.
Implementation
final SpannableGridSize gridSize;