use the build in sizes like @dimen/text_size_body_2_material
or style/TextAppearance.Material.Headline
.
Simple helper file for standard text sizes in material design. The sizes are provided by the material design documentation https://www.google.com/design/spec/style/typography.html#typography-roboto
Too many type sizes and styles at once can wreck any layout. A typographic scale is a limited set of type sizes that work well together, along with the layout grid. The basic set of styles are based on a typographic scale of 12, 14, 16, 20, and 34.
This page shows contradictory information to the material design documentation (see link). In the material design Body 1 uses regular font and a bigger font size than Body 2, making Body 1 more bold. On this page it is the other way around Body 2 uses medium font and same font size as Body 1, making Body 2 more bold.