Android 系统的语言加载功能的部分片段

安卓系统启动时，根据系统当前的属性信息，设定了语言和区域参数

 

所依赖的属性参数，可以在系统编译时指定。下面的两个文件是有关通过当前系统属性设置 Locale 的动作：

1. frameworks/base/core/jni/AndroidRuntime.cpp

里面有个方法，方法上有说明，表明了根据几个属性值加载，先判断的属性如果不为空，就不会去判断后面的属性了，如下：

/*
 * Read the persistent locale. Inspects the following system properties
 * (in order) and returns the first non-empty property in the list :
 *
 * (1) persist.sys.locale
 * (2) persist.sys.language/country/localevar (country and localevar are
 * inspected iff. language is non-empty.
 * (3) ro.product.locale
 * (4) ro.product.locale.language/region
 *
 * Note that we need to inspect persist.sys.language/country/localevar to
 * preserve language settings for devices that are upgrading from Lollipop
 * to M. The same goes for ro.product.locale.language/region as well.
 */
const std::string readLocale()