Update README_EN.md

Author: CarGuo

README_EN.md

@@ -28,6 +28,8 @@ With the use and feedback of the project, will user experience and function opti
 * ### [Flutter 完整开发实战详解(六、 深入Widget原理)](https://juejin.im/post/5c7e853151882549664b0543 )
 * ### [Flutter 完整开发实战详解(七、 深入布局原理)](https://juejin.im/post/5c8c6ef7e51d450ba7233f51 )
 * ### [Flutter 完整开发实战详解(八、 实用技巧与填坑)](https://juejin.im/post/5c9e328251882567b91e1cfb)
+* ### [Flutter 完整开发实战详解(九、 深入绘制原理)](https://juejin.im/post/5ca0e0aff265da309728659a)
+