After we known all principles in class level and component level, finally we reached Architecutre level. In this post, we will summarize all architecture level knowedge concepts quickly and finish this book for now, this book has much more useful stuffs that we are not covered, so we will come back and revisit someday after we have more understanding about software architecture.
In last post we talked about programming paradigms and SOLID principles. This is far more than enough to understand about architecture, so today let’s continue on “Design Principles” and see more of them that need to follow when thinking like an architect.
在Android开发的大部分场景里，我们需要构建各种各样的UI界面用于与用户进行交互。很多UI设计看起来很简单也很清晰，但一旦开始上手设计，就会发现：设计师轻松画出的各个UI组件，它们的排列，间隔，对齐，大小，其实没有那么容易摆放正确。再加上对于安卓系统的手机，屏幕大小尺寸更是多种多样。这是我们就需要用到页面布局（UI Layout）这个工具。那么今天就来看看Android中关于页面布局的一些概念和知识。
今天的内容是这周工作中出现的一个相关内容的学习：多线程（Multi-thread）。多线程可以极大地减少程序在并发执行时所付出的时空开销，提高操作系统的并发性能。在Android的开发中，多线程是非常重要的一环，而相信很多人也在面试中被问到过不止一次进程（Process）与线程（Thread）的区别。那么我们就来看看和Android相关的多线程组件Process，Thread，Looper，Handler各自的概念和实例。
之前的Android开发笔记之基础篇(一)中主要讲到了一些关于Android Components的基本概念以及它们的异同。今天就来讲解一下关于Activity中涉及UI部分的三个核心组件：Activity，Fragment和Dialog。它们基本承担起了APP中所有的图形界面和交互逻辑，也是面向用户最直观的展现。
因为最近开始系统地学习Android开发，所以在这里记录一下所学到的Android内容做一个整理。既算是对已学到知识的总结和梳理，也可以检查自己理解中出现的问题，和大家共同讨论一下。因为是第一次写东西，所以有什么不详细，不清楚，不准确的地方，还希望可以指正，我们共同讨论，共同进步。
Clean Architecture is one of the series book that written by “Uncle Bob”. In last post, I writed a summary of the Clean Code. It is super useful for begineers. But as we going deeper, we need take a step back and see the “big picture” – software architecture, which is all this book talk about.
Recently I read this book
Dependency Injection is a huge topic in Android development and it’s very important because it can give us a clean, well-designed, easy-to-change environment no matter we develop new features or implement any testing. So here is some thoughts about DI and an useful framework which helps you do all dirty jobs behind the scene.
