Android 10 不能在内存根目录创建文件夹的问题

Android 10 SDK版本29无法在内存根目录创建文件夹？

查阅文档得知android 10添加了沙盒机制
我们应该如何解决这个问题呢？

解决方法

1）直接跳过沙盒特性，沿用以往的做法
在manifest文件的application节点中添加

android:requestLegacyExternalStorage="true"

2）根据新特性，实现Android10的适配

 public static String getSDPath(Context context) {
        File sdDir = null;
        boolean sdCardExist = Environment.getExternalStorageState().equals(
                Environment.MEDIA_MOUNTED);// 判断sd卡是否存在
        if (sdCardExist) {
            if (Build.VERSION.SDK_INT >= 29) {
                //Android10之后
                sdDir = context.getExternalFilesDir(null);//获取应用所在根目录/Android/data/your.app.name/file/ 也可以根据沙盒机制传入自己想传的参数，存放在指定目录
            } else {
                sdDir = Environment.getExternalStorageDirectory();// 获取SD卡根目录
            }
        } else {
            sdDir = Environment.getRootDirectory();// 获取跟目录
        }
        return sdDir.toString();
    }

获取指定沙盒文件夹路径请参阅：

//废弃方法
//不再用以下代码获取文件根目录了
Environment.getExternalStorageDirectory();
Environment.getExternalStoragePublicDirectory();

//获取沙盒下的文件目录
//沙盒下的图片文件夹
File filePictures = getExternalFilesDir(Environment.DIRECTORY_PICTURES);

//Environment下的文件夹名称常量
//只需要调用，不需要创建，如果手机中没有对应的文件夹，则系统会自动生成
//以下为源码中的各个文件夹名称描述
 /**
     * Standard directory in which to place any audio files that should be
     * in the regular list of music for the user.
     * This may be combined with
     * {@link #DIRECTORY_PODCASTS}, {@link #DIRECTORY_NOTIFICATIONS},
     * {@link #DIRECTORY_ALARMS}, and {@link #DIRECTORY_RINGTONES} as a series
     * of directories to categories a particular audio file as more than one
     * type.
     */
    public static String DIRECTORY_MUSIC = "Music";

    /**
     * Standard directory in which to place any audio files that should be
     * in the list of podcasts that the user can select (not as regular
     * music).
     * This may be combined with {@link #DIRECTORY_MUSIC},
     * {@link #DIRECTORY_NOTIFICATIONS},
     * {@link #DIRECTORY_ALARMS}, and {@link #DIRECTORY_RINGTONES} as a series
     * of directories to categories a particular audio file as more than one
     * type.
     */
    public static String DIRECTORY_PODCASTS = "Podcasts";

    /**
     * Standard directory in which to place any audio files that should be
     * in the list of ringtones that the user can select (not as regular
     * music).
     * This may be combined with {@link #DIRECTORY_MUSIC},
     * {@link #DIRECTORY_PODCASTS}, {@link #DIRECTORY_NOTIFICATIONS}, and
     * {@link #DIRECTORY_ALARMS} as a series
     * of directories to categories a particular audio file as more than one
     * type.
     */
    public static String DIRECTORY_RINGTONES = "Ringtones";

    /**
     * Standard directory in which to place any audio files that should be
     * in the list of alarms that the user can select (not as regular
     * music).
     * This may be combined with {@link #DIRECTORY_MUSIC},
     * {@link #DIRECTORY_PODCASTS}, {@link #DIRECTORY_NOTIFICATIONS},
     * and {@link #DIRECTORY_RINGTONES} as a series
     * of directories to categories a particular audio file as more than one
     * type.
     */
    public static String DIRECTORY_ALARMS = "Alarms";

    /**
     * Standard directory in which to place any audio files that should be
     * in the list of notifications that the user can select (not as regular
     * music).
     * This may be combined with {@link #DIRECTORY_MUSIC},
     * {@link #DIRECTORY_PODCASTS},
     * {@link #DIRECTORY_ALARMS}, and {@link #DIRECTORY_RINGTONES} as a series
     * of directories to categories a particular audio file as more than one
     * type.
     */
    public static String DIRECTORY_NOTIFICATIONS = "Notifications";

    /**
     * Standard directory in which to place pictures that are available to
     * the user.  Note that this is primarily a convention for the top-level
     * public directory, as the media scanner will find and collect pictures
     * in any directory.
     */
    public static String DIRECTORY_PICTURES = "Pictures";

    /**
     * Standard directory in which to place movies that are available to
     * the user.  Note that this is primarily a convention for the top-level
     * public directory, as the media scanner will find and collect movies
     * in any directory.
     */
    public static String DIRECTORY_MOVIES = "Movies";

    /**
     * Standard directory in which to place files that have been downloaded by
     * the user.  Note that this is primarily a convention for the top-level
     * public directory, you are free to download files anywhere in your own
     * private directories.  Also note that though the constant here is
     * named DIRECTORY_DOWNLOADS (plural), the actual file name is non-plural for
     * backwards compatibility reasons.
     */
    public static String DIRECTORY_DOWNLOADS = "Download";

    /**
     * The traditional location for pictures and videos when mounting the
     * device as a camera.  Note that this is primarily a convention for the
     * top-level public directory, as this convention makes no sense elsewhere.
     */
    public static String DIRECTORY_DCIM = "DCIM";

    /**
     * Standard directory in which to place documents that have been created by
     * the user.
     */
    public static String DIRECTORY_DOCUMENTS = "Documents";

    /**
     * Standard directory in which to place screenshots that have been taken by
     * the user. Typically used as a secondary directory under
     * {@link #DIRECTORY_PICTURES}.
     */
    public static String DIRECTORY_SCREENSHOTS = "Screenshots";

    /**
     * Standard directory in which to place any audio files which are
     * audiobooks.
     */
    public static String DIRECTORY_AUDIOBOOKS = "Audiobooks";