This layout arranges child views in a grid layout. It is similar to the Table Layout, but a bit simpler.
It creates a coordinate system based on given number of columns and rows. All the columns has the
same width, and all rows has the same height. You position child views inside the coordinate system
by specifying a value for x and y. Child views can also span multiple columns and/or rows using
the colspan and rowspan attribute.
Spacing between columns and rows are controlled by the padX and padY attribute.
For demo, see Grid layout demo.