android - android studio SDK工具中 "ConstraintLayout for android"和 "Solver for ConstraintLayout"的区别

Question

在android studio SDK工具中有两个ConstraintLayout选项，一个是ConstraintLayout for android，另一个是Solver for ConstraintLayout。

截图如下:

这两个选项有什么区别？

Answer 1

求解器的作用。

为了将约束转化为实际位置和大小，约束求解器应用 Cassowary 算法来找到解决方案。看看这篇文章，了解这种布局的工作原理以及为什么包中有解算器。 https://www.bignerdranch.com/blog/constraintlayout-vs-auto-layout-how-do-they-compare/

约束布局到底是什么？

如 android 所述 “一个布局，其中子级的位置被描述为相对于彼此或父级的约束。”

https://android.googlesource.com/platform/frameworks/opt/sherpa/+/gradle_2.0.0/constraintlayout/src/main/java/android/support/constraint/ConstraintLayout.java

Constraint Layout is equations describing positional relation between views and Solver solves those equations to help android determine positions (x,y,z, length, width) where views should be drawn.