我希望我的应用程序的用户能够删除DCIM文件夹(它位于SD卡上并包含子文件夹)。

这可能吗?如果可能,怎么可能?


当前回答

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();
}

其他回答

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();
}

这种方法适用于只包含文件的文件夹,但如果您正在寻找还包含子文件夹的场景,则需要递归

此外,您应该捕获返回的返回值,以确保允许您删除该文件

,包括

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

在你的清单上

void DeleteRecursive(File dir)
{
    Log.d("DeleteRecursive", "DELETEPREVIOUS TOP" + dir.getPath());
    if (dir.isDirectory())
    {
        String[] children = dir.list();
        for (int i = 0; i < children.length; i++)
        {
            File temp = new File(dir, children[i]);
            if (temp.isDirectory())
            {
                Log.d("DeleteRecursive", "Recursive Call" + temp.getPath());
                DeleteRecursive(temp);
            }
            else
            {
                Log.d("DeleteRecursive", "Delete File" + temp.getPath());
                boolean b = temp.delete();
                if (b == false)
                {
                    Log.d("DeleteRecursive", "DELETE FAIL");
                }
            }
        }

    }
    dir.delete();
}

这是另一种(现代)解决方法。

public class FileUtils {
    public static void delete(File fileOrDirectory) {
        if(fileOrDirectory != null && fileOrDirectory.exists()) {
            if(fileOrDirectory.isDirectory() && fileOrDirectory.listFiles() != null) {      
                Arrays.stream(fileOrDirectory.listFiles())
                      .forEach(FileUtils::delete);
            }
            fileOrDirectory.delete();
        }
    }
}

从API 26开始在Android上运行

public class FileUtils {

    public static void delete(File fileOrDirectory)  {
        if(fileOrDirectory != null) {
            delete(fileOrDirectory.toPath());
        }
    }

    public static void delete(Path path)  {
        try {
            if(Files.exists(path)) {
                Files.walk(path)
                        .sorted(Comparator.reverseOrder())
                        .map(Path::toFile)
//                      .peek(System.out::println)
                        .forEach(File::delete);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

这是kotlin选项。它运行得很好。

fun executeDelete(context: Context, paths: List<String>): Int {
    return try {
        val files = paths.map { File(it) }
        val fileCommands = files.joinToString(separator = " ") {
            if (it.isDirectory) "'${it.absolutePath}/'" else "'${it.absolutePath}'"
        }
        val command = "rm -rf $fileCommands"
        val process = Runtime.getRuntime().exec(arrayOf("sh", "-c", command))
        val result = process.waitFor()
        if (result == 0) {
            context.rescanPaths(paths)
        }
        result
    } catch (e: Exception) {
        -1
    }
}

//避免在一行中多次调用,它可以删除整个文件夹内容

fun Context.rescanPaths(paths: List<String>, callback: (() -> Unit)? = null) {
if (paths.isEmpty()) {
    callback?.invoke()
    return
}

var cnt = paths.size
MediaScannerConnection.scanFile(applicationContext, paths.toTypedArray(), null) { _, _ ->
    if (--cnt == 0) {
        callback?.invoke()
    }
}
}

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'