你可以像这样递归地删除文件和文件夹:

void deleteRecursive(File fileOrDirectory) {
    if (fileOrDirectory.isDirectory())
        for (File child : fileOrDirectory.listFiles())
            deleteRecursive(child);

    fileOrDirectory.delete();
}

让我告诉你第一件事你不能删除DCIM文件夹，因为它是一个系统文件夹。当你在手机上手动删除它时，它会删除该文件夹的内容，但不会删除DCIM文件夹。您可以通过以下方法删除其内容:

根据评论更新

File dir = new File(Environment.getExternalStorageDirectory()+"Dir_name_here"); 
if (dir.isDirectory()) 
{
    String[] children = dir.list();
    for (int i = 0; i < children.length; i++)
    {
       new File(dir, children[i]).delete();
    }
}

//To delete all the files of a specific folder & subfolder
public static void deleteFiles(File directory, Context c) {
    try {
        for (File file : directory.listFiles()) {
            if (file.isFile()) {
                final ContentResolver contentResolver = c.getContentResolver();
                String canonicalPath;
                try {
                    canonicalPath = file.getCanonicalPath();
                } catch (IOException e) {
                    canonicalPath = file.getAbsolutePath();
                }
                final Uri uri = MediaStore.Files.getContentUri("external");
                final int result = contentResolver.delete(uri,
                        MediaStore.Files.FileColumns.DATA + "=?", new String[]{canonicalPath});
                if (result == 0) {
                    final String absolutePath = file.getAbsolutePath();
                    if (!absolutePath.equals(canonicalPath)) {
                        contentResolver.delete(uri,
                                MediaStore.Files.FileColumns.DATA + "=?", new String[]{absolutePath});
                    }
                }
                if (file.exists()) {
                    file.delete();
                    if (file.exists()) {
                        try {
                            file.getCanonicalFile().delete();
                        } catch (IOException e) {
                            e.printStackTrace();
                        }
                        if (file.exists()) {
                            c.deleteFile(file.getName());
                        }
                    }
                }
            } else
                deleteFiles(file, c);
        }
    } catch (Exception e) {
    }
}

这是你的解决方案，它也将刷新画廊以及。

如果该目录在Java中有子目录或文件，则不能删除该目录。试试这两行简单的解决方案。这将删除目录和目录内的竞争。

File dirName = new File("directory path");
FileUtils.deleteDirectory(dirName);

在gradle文件中添加这一行并同步项目

compile 'org.apache.commons:commons-io:1.3.2'  

最快最简单的方法:

public static boolean deleteFolder(File removableFolder) {
        File[] files = removableFolder.listFiles();
        if (files != null && files.length > 0) {
            for (File file : files) {
                boolean success;
                if (file.isDirectory())
                    success = deleteFolder(file);
                else success = file.delete();
                if (!success) return false;
            }
        }
        return removableFolder.delete();
}

你可以像这样递归地删除文件和文件夹:

void deleteRecursive(File fileOrDirectory) {
    if (fileOrDirectory.isDirectory())
        for (File child : fileOrDirectory.listFiles())
            deleteRecursive(child);

    fileOrDirectory.delete();
}