Changes

This chapter will introduce the basics of the GridLayout class before exploring the creation of a GridLayout-based user interface using Android Studio Designer. Directly creating GridLayout user interface designs using XML layout resources as an alternative to using the Designer tool will be covered in the next chapter, entitled Working with the Android GridLayout using XML Layout Resources.

The purpose of the GridLayout is to allow child views to be positioned in a grid arrangement. The GridLayout essentially consists of a number of invisible horizontal and vertical grid lines that serve to divide the layout view into a series of rows and columns, with each intersecting row and column forming a cell which can, in turn, contain one or more views. The grid lines are referred to as indices, which are numbered starting at 0 for the line at the leading edge of the layout. Row and column numbering also starts at 0 beginning in the top left hand corner of the grid.