由于并不是每個app都會用到NDK,事實上,大多數app都不需要用到NDK,因此,NDK的安裝獨立成一節,不感興趣的筒靴可以跳過,NDK的安裝相對簡單,只需要到[NDK Downloads](https://developer.android.com/ndk/downloads/index.html)或者[AndroidDevTools](http://www.androiddevtools.cn/)下載NDK的壓縮包,然后解壓到本地目錄中即可。
接著在Android工程根目錄的local.properties文件中新增ndk.dir變量,其值指向ndk絕對路徑,例如:
~~~
## This file is automatically generated by Android Studio.
# Do not modify this file -- YOUR CHANGES WILL BE ERASED!
#
# This file should *NOT* be checked into Version Control Systems,
# as it contains information specific to your local configuration.
#
# Location of the SDK. This is only used by Gradle.
# For customization when using a Version Control System, please read the
# header note.
sdk.dir=/Users/guhaoxin/Library/Android/sdk
ndk.dir=/Users/guhaoxin/Library/Android/android-ndk-r10
~~~
NDK的使用主要有兩種形式,一種是拿到第三方的so文件,我們通過JNI封裝其提供的native接口給Java層使用另一種是自己使用C/C++編寫底層代碼,然后編譯生成so文件,接著重復第一種的做法。具體實現還是比較麻煩的,篇幅比較大,需要用到的筒靴可以參考以下這幾篇文章:
* [NDK with Android Studio](http://www.shaneenishry.com/blog/2014/08/17/ndk-with-android-studio/)
* [Android Studio, gradle and NDK integration](http://ph0b.com/android-studio-gradle-and-ndk-integration/)
* [Share code between projects in Android Studio](http://blog.gaku.net/share-code-between-projects-in-android-studio/)
* [Using custom Android.mk with Gradle/Android Studio](http://blog.gaku.net/ndk/)
等有時間再結合實際項目整理一篇Android Studio+NDK的入門指引。