SystemBarTintManager.java 文件源码

@TargetApi(14)
private boolean hasNavBar(Context context) {
    Resources res = context.getResources();
    int resourceId = res.getIdentifier(SHOW_NAV_BAR_RES_NAME, "bool", "android");
    if (resourceId != 0) {
        boolean hasNav = res.getBoolean(resourceId);
        // check override flag (see static block)
        if ("1".equals(sNavBarOverride)) {
            hasNav = false;
        } else if ("0".equals(sNavBarOverride)) {
            hasNav = true;
        }
        return hasNav;
    } else { // fallback
        return !ViewConfiguration.get(context).hasPermanentMenuKey();
    }
}