android - CreateTempFile 在图片文件夹中返回没有这样的文件或目录？

Question

这是我的代码:

String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
String imageFileName = "JPEG_" + timeStamp + "_";
File storageDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
File image = File.createTempFile(
      imageFileName,  /* prefix */
      ".jpg",         /* suffix */
      storageDir      /* directory */
);

但是，我的应用程序间歇性地在 File.createTempFile 处抛出错误:

java.io.IOException: open failed: ENOENT (No such file or directory).

来自文件的文档:

Parameters:
prefix the prefix to the temp file name.
suffix the suffix to the temp file name.
directory the location to which the temp file is to be written, or null for the default location for temporary files, which is taken from the "java.io.tmpdir" system property. It may be necessary to set this property to an existing, writable directory for this method to work properly.

Returns:
the temporary file.

Throws:
IllegalArgumentException - if the length of prefix is less than 3.
IOException - if an error occurs when writing the file.

写入临时文件失败的可能性有哪些？因为我指向外部存储并且我的外部 SD 卡插入设备内部。

Answer 1

getExternalStoragePublicDirectory() 的 javadoc特别指出:

this directory may not yet exist, so you must make sure it exists before using it such as with File.mkdirs().

在那之后，我认为你还应该检查一下目录是否存在。