I guess many of us have already stumbled over "winmail.dat" or "attxxxx.dat" attachments in our Android email clients.
These attachment names usually occour, when somebody who is using a Microsoft Outlook EMail client sends you an certain RTF (rich text format) email with attachments. MS Outlook then packs these attachments into a TNEF (Transport-Neutral Encapsulation Format) envelope. Other MS Outlook Clients can deal with this format, but, however, most of the other email clients cannot! They will receive instead an attachment with the above mentioned naming and can basically do nothing with it.
While this is a well known (and annoying) circumstance there are already plug-ins for many open email clients such as Mozilla Thunderbird. For Android however there seemed to be nothing (and I have been doing quite some research on it).
So I finally decided to write my own app to deal with TNEF attachments. Luckily there was already an existing Java package which could do the extraction job so that I "only" had to create the Android app around it and do some debugging on the original code. My kudos here go to Amichai Rothman for his Java TNEF package (http://www.freeutils.net/source/jtnef/)!!
I originally created this application for my own purposes but then I thought it is worth while sharing it with the community. It is already bi-lingual (english and localized to german) and should get its job done.
The app itself registers as a handler for *.dat or *.DAT files and for email attachments. When you e.g. try to open a "winmail.dat" attachment from within your Android email client or a "winmail.dat" file with your file browser the app should be launched or you see a chooser box where you can select this app. When you do so you will see an alert box. When you press "Ok" the app will try to extract the contents of "winmail.dat" to a local folder. The default for this folder is "/sdcard/winmail". After it has successfully completed the extraction the app leaves a notification. When you open the the notification it will show you the contents of the target folder in another alert box. You can then use any file manager to browser to the target directory to access the real attachments out of the "winmail.dat" envelope.
If you launch the app directly it will present you a setup screen with some explanation on it and the possibility to specify your own target directory to where the extracted files should go. Furthermore, the check boy allows you to decide whether each attachment / file should be extracted to an own subdirectory.
The only system privileges that the app acquires upon installation are to be able to write to the external storage (sdcard) and to read from Google Mail.
我想我们很多人都已经绊了“winmail.dat的”还是我们的Andr??oid邮件客户端“attxxxx.dat”的附件。
这些附件名称通常occour时，谁正在使用微软的Outlook电子邮件客户端某人向你带有附件的某些RTF（富文本格式）的电子邮件。 MS Outlook然后打包这些附件到TNEF（传输中性封装格式）的信封。其他MS Outlook客户端可以用这个格式的处理，但是，但是，大多数其他电子邮件客户端不能！它们将接收代替附件具有上述命名和可以基本上什么也不做它。
虽然这是一个众所周知的（和恼人的）的情况下，已经有插件许多打开电子邮件客户端，如Mozilla Thunderbird中。对于Android然而，似乎有什么（我一直在做的相当一些研究就可以了）。
所以，我终于决定写我自己的应用程序来处理TNEF附件。幸运的是，已经有现有的Java包，它可以做的提取工作，使我“才”不得不创建一个围绕它的Andr??oid应用程序，并做原代码一些调试。我在这里的荣誉去阿米海罗斯曼对他的Java TNEF封装（http://www.freeutils.net/source/jtnef/）！
我最初创建这个应用程序为我自己的目的，但转念一想，同时与社会分享这很值得。这已经是双语（英语和本地化德国），并应该得到它的工作做好。
该应用程序本身注册为处理程序的* .dat或* .DAT文件和电子邮件附件。当你如尝试从Android的电子邮件客户端或一个“winmail.dat的”文件，文件的浏览器应用程序应该是启动或看到一个选择器框，您可以选择该应用程序中打开一个“winmail.dat的”附件。当你这样做，你会看到一个提示框。当您按下“确定”按钮，程序会尝试提取“winmail.dat的”内容到本地文件夹。默认此文件夹是“/ SD卡/ Winmail邮件”。之后它已经成功地完成了提取应用程序留下了通知。当您打开通知它会告诉你在另外一个警告框目标文件夹中的内容。然后，您可以使用任何文件管理器来浏览到目标目录访问真正的附加了“winmail.dat的”信封。
如果直接启动应用程序，它会为你展示它的一些解释，并指定自己的目标目录，其中提取的文件应该去的可能性设置屏幕。此外，检查男孩可以决定每个附件/文件是否应被提取到自己的子目录。
该应用程序获取安装时唯一的系统权限是能够写入到外部存储（SD卡）和谷歌邮件阅读。

Changed minimum Android Version to 4.2.2
Fixed false handling of target director