Encapsulated common Android controls, such as sletextbutton, sleimagebutton, sleconstraintlayout, sleframelayout, slelinearlayout, slerelativelayout, etc. Make the control have the functions of shape and selector, and save the cumbersome steps of writing shape or selector files. In addition, it supports n color gradients, which makes up for the deficiency that the native shape file only supports three colors (startcolor / centercolor / endcolor).