无法用File类删除文件

Im trying to delete a music file through my App but can't achieve that. Ive checked with

我试图通过我的应用删除一个音乐文件，但无法实现。我检查了

boolean exists = temp.exists();
boolean isFile = temp.isFile();

if there true and yes they are. These methods returns me true. But when I come to the delete method :

如果它们是真的，它们是真的。这些方法返回true。但是当我提到删除方法时:

boolean deleted = temp.delete();

It returns me False and the file is not getting deleted. There are no Exception throws just a false return to my deleted variable.

它返回False，文件没有被删除。没有例外，只是向已删除的变量抛出一个错误的返回。

Im also using these permissons :

我也使用这些permisson:

<uses-permission android:name="android.permission.MEDIA_CONTENT_CONTROL" />
<uses-permission android:name="android.permission.WAKE_LOCK" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>
<uses-permission android:name="android.permission.ACTION_HEADSET_PLUG"/>

Someone got an Idea for a solution ? (Or other classes I can use ?)

有人有办法解决吗?(或者其他我可以使用的类?)

Edit: Thats my full code

编辑:这是我的全部代码

File temp = new File(str_path);

boolean exists = temp.exists();
boolean isFile = temp.isFile();

if (exists)) {
    boolean deleted = temp.delete();
    if (deleted) {
        Toast.makeText(context, "Successful deleted " + Title_Artist, Toast.LENGTH_SHORT).show();
            } else {
                Toast.makeText(context, "Not able to delete file " + Title_Artist, Toast.LENGTH_SHORT).show();
            }
        }

(And I checked while debuging if the object has his path in it and it have it)

(我在调试时检查了对象是否有它的路径，并且它有它)

4 个解决方案

#1

Delete file music you must do two task:

删除文件音乐你必须做两个任务:

Delete file in Storage.

删除文件的存储。

public static boolean delete(File path) {
    boolean result = true;
    if (path.exists()) {
        if (path.isDirectory()) {
            for (File child : path.listFiles()) {
                result &= delete(child);
            }
            result &= path.delete(); // Delete empty directory.
        }
        if (path.isFile()) {
        result &= path.delete();
        }
        if (!result) {
            Log.e("Delete", "Delete failed;");
        }
        return result;
    } else {
        Log.e("Delete", "File does not exist.");
        return false;
    }
}

Delete file from MediaStore:

从MediaStore删除文件:

public static void deleteFileFromMediaStore(final ContentResolver contentResolver, final File file) {
    int sdk = android.os.Build.VERSION.SDK_INT;
    if (sdk >= android.os.Build.VERSION_CODES.HONEYCOMB) {
       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});
            }
        }
    }
}

You can reset/rescan MediaStore instead of do some code above.

您可以重置/重新扫描MediaStore，而不是执行上面的一些代码。

Note: If you delete from SD card and android 4.4 +

注意:如果从SD卡和android 4.4 +中删除

Change for Android 4.4+ : Apps are not allowed to write (delete, modify ...) to external storage except to their package-specific directories.

Android 4.4+的改变:除了特定于包的目录之外，应用程序不允许将(删除、修改…)写入外部存储。

#2

The path from your comment looks like the file is on a removable SD card. You need special permissions on Android 4.4+ to manage or delete files on an SD card. You will need to use DocumentFile#delete().

您的注释的路径看起来像是文件在一个可移动的SD卡上。您需要Android 4.4+上的特殊权限来管理或删除SD卡上的文件。您将需要使用DocumentFile#delete()。

For help accessing files on a removable SD card using DocumentFile see the following * post:

有关使用DocumentFile访问可移动SD卡上的文件，请参阅以下*文章:

How to use the new SD card access API presented for Android 5.0 (Lollipop)?

如何使用为Android 5.0 (Lollipop)提供的新的SD卡访问API ?

There is also a hack that might work without using DocumentFile as explained by the developer of FX file manager here: http://forum.xda-developers.com/showpost.php?p=52151865

还有一种方法可以在不使用DocumentFile的情况下工作，如FX文件管理器的开发人员在这里所解释的:http://forum.xdda -developers.com/showpost.php?

#3

Since you are checking that the file exists, there can only be one reason you can not delete the file: you don't have permissions to do it.

由于您正在检查该文件是否存在，因此您不能删除该文件的唯一原因是:您没有执行该文件的权限。

An app can not delete system files, or files of other apps.

应用程序不能删除系统文件或其他应用程序的文件。

#4

Suppose your file path is

假设您的文件路径是

Environment.getExternalStorageDirectory().getPath()
                        + "/Music"
                        + "/"
                        + "song.mp3"

delete it like this

这样删除

File dir = new File(Environment.getExternalStorageDirectory()
                        .getPath()
                        + "/Music");

if (dir.isDirectory()) {new File(dir, song.mp3).delete();}

if you want to delete all the files in music folder do this

如果你想删除音乐文件夹中的所有文件，请这样做

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

#1