在了解存储路径之前，先来看看Android QQ的文件管理界面，了解一下QQ的数据文件路径来源，到底是来源于什么地方？
我的文件：是指放在QQ指定目录下的文件：/tencent/QQfile_recv/（顺便说一下微信的存储目录：/tencent/MicroMsg/Download/）
手机内存：其实是内部存储的根目录，在ES文件浏览器对应的是根目录，路径为：Environment.getDataDirectory().getParentFile()
SD卡：这里的SD卡是指内置的SD卡，路径为：Environment.getExternalStorageDirectory()
扩展卡内存：外置SD卡
主要方法路径
Environment.getDataDirectory()/data
Environment.getDownloadCacheDirectory()/cache
Environment.getRootDirectory()/system
获取路径方式是Environment.getExternalStorageDirectory()/storage/sdcard0
方法路径
Environment.getExternalStoragePublicDirectory(DIRECTORY_ALARMS)/storage/sdcard0/Alarms
Environment.getExternalStoragePublicDirectory(DIRECTORY_DCIM)/storage/sdcard0/DCIM
Environment.getExternalStoragePublicDirectory(DIRECTORY_DOWNLOADS)/storage/sdcard0/Download
Environment.getExternalStoragePublicDirectory(DIRECTORY_MOVIES)/storage/sdcard0/Movies
Environment.getExternalStoragePublicDirectory(DIRECTORY_MUSIC)/storage/sdcard0/Music
Environment.getExternalStoragePublicDirectory(DIRECTORY_NOTIFICATIONS)/storage/sdcard0/Notifications
Environment.getExternalStoragePublicDirectory(DIRECTORY_PICTURES)/storage/sdcard0/Pictures
Environment.getExternalStoragePublicDirectory(DIRECTORY_PODCASTS)/storage/sdcard0/Podcasts
Environment.getExternalStoragePublicDirectory(DIRECTORY_RINGTONES)/storage/sdcard0/Ringtones
上面的九个方法对应的就是SD卡的九大公有目录，Google官方建议我们数据应该存储在私有目录下，不建议存储在公有目录下或其他地方
就是在外部存储的App的包名下，如：/storage/emulated/0/Android/data/cwj.test(包名)/files/test
方法路径
getExternalFilesDir()/storage/emulated/0/Android/data/cwj.test(包名)/files/test
getExternalCacheDir/storage/emulated/0/Android/data/cwj.test(包名)/cache/test
一般情况下有包名的路径我们都是调用Context中的方法来获得，没有包名的路径，我们直接调用Environment中的方法获得。
扩展内存就是我们插入的外置SD卡，获取扩展内存的路径有点难度，不过Google很牛逼，哈哈，代码如下：
private static String getExtendedMemoryPath(Context mContext) {
StorageManager mStorageManager = (StorageManager) mContext.getSystemService(Context.STORAGE_SERVICE);
Class storageVolumeClazz = null;
try {
storageVolumeClazz = Class.forName("android.os.storage.StorageVolume");
Method getVolumeList = mStorageManager.getClass().getMethod("getVolumeList");
Method getPath = storageVolumeClazz.getMethod("getPath");
Method isRemovable = storageVolumeClazz.getMethod("isRemovable");
Object result = getVolumeList.invoke(mStorageManager);
final int length = Array.getLength(result);
for (int i = 0; i < length; i++) {
Object storageVolumeElement = Array.get(result, i);
String path = (String) getPath.invoke(storageVolumeElement);
boolean removable = (Boolean) isRemovable.invoke(storageVolumeElement);
if (removable) {
return path;
}
}
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
} catch (NoSuchMethodException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
}
return null;
}
该方法主要是通过反射的方式使用在sdk中被 隐藏 的类 StroageVolume 中的方法getVolumeList()，获取外部存储的路径。
Log.e("cwj", "外置SD卡路径 = " + getStoragePath(this));
Log.e("cwj", "内置SD卡路径 = " + Environment.getExternalStorageDirectory().getAbsolutePath());
Log.e("cwj", "手机内存根目录路径 = " + Environment.getDataDirectory().getParentFile().getAbsolutePath());
from:http://itfeifei.win/2017/03/17/Android%E5%AD%98%E5%82%A8%E8%B7%AF%E5%BE%84%E4%BD%A0%E4%BA%86%E8%A7%A3%E5%A4%9A%E5%B0%91/
