Linear layouts
Choosing between a relative layout and a linear one is normally very simple. If your components line up from side to side on top of each other, then a linear layout is the obvious choice. Although it is quite possible to nest view groups, for more complex layouts, the relative version is often the best choice. This is largely because nesting layouts is resource hungry and deep hierarchies should be avoided where possible. The relative layout can be used to create a huge number of intricate layouts with very little need for nesting.
Whichever form best suits our needs, once we begin testing our layouts on screens of different shapes, or even rotate a screen through 90°, we soon see that all the thought that we put into creating components with pleasing proportions is lost. Very often, these issues can be remedied by positioning elements using gravity properties and scaling them with the weight property.
Weight and gravity
Being able to set position and proportion without...