AOSP的helloworld，修改计算器源码并编译弹出Toast

source build/envsetup.sh

执行之后可以用

  - croot: Changes directory to the top of the tree.
  - m: Makes from the top of the tree.
  - mm: Builds all of the modules in the current directory.
  - mmm: Builds all of the modules in the supplied directories.
  - cgrep: Greps on all local C/C++ files.
  - jgrep: Greps on all local Java files.
  - resgrep: Greps on all local res/*.xml files.
  - godir: Go to the directory containing a file.

你去

packages/apps/你想改的应用/

 

别忘记给import Toast

编译img

455 mmm packages/apps/Calculator/
456 make snod
457 fastboot flash system out/target/product/bullhead/system.img