图像/ JPEG＆QUOT; MIME类型从＆QUOT切换;到＆QUOT;图像/ PNG＆QUOT; [英] MIME type switched from "image/jpeg" to "image/png"

问题描述

下面的2 code片段展示我遇到了与新的谷歌云端硬盘Android API的问题/谷歌播放服务4.2（libver 15）。抑或是一个功能，我不知道？所有的错误检查和初始化，以保持code简单的被删除。

The following 2 code snippets demonstrate the problem I ran into with the NEW Google Drive Android API / Google Play Services 4.2 (libver 15). Or is it a feature I don't know about? All error checking and initialization is removed in order to keep the code simple.

1 / I制造形象/ JPEGMIME类型的图片;

1/ I create a picture of "image/jpeg" MIME type;

GoogleApiClient mGAC;
byte[] jpgBuffer;
DriveFolder fldr;

ContentsResult rslt = Drive.DriveApi.newContents(mGAC).await();
Contents cont = rslt.getContents();
cont.getOutputStream().write(jpgBuffer);
MetadataChangeSet meta = new MetadataChangeSet.Builder()
  .setTitle("foo.jpg").setMimeType("image/jpeg")
  .build();
fldr.createFile(mGAC, meta, cont);

一切都在驱动器很好，很正常。图片是存在的，看起来棒极了，我甚至可以将其发送给我的妈妈。但是，这不是我后。我想在我的Andr​​oid应用程序的其他部分进行检索。

Everything is nice and dandy in the Drive. Image is there, looking great, I can even send it to my mom. But this is not what I'm after. I would like to retrieve it in another part of my Android app.

2 /所以我试试这个：

2/ So I try this:

Query query = new Query.Builder().addFilter(
  Filters.eq(SearchableField.MIME_TYPE, "image/jpeg")
).build();
MetadataBufferResult rslt = Drive.DriveApi.query(mGAC, query).await();
for (Metadata md : rslt.getMetadataBuffer()) {
  Log.d("TAG", md.getTitle() + " " + md.getMimeType());
}

结果：大又肥罢了。

Result: big, fat NOTHING.

我不会放弃的，所以下一个合乎逻辑的步骤是寻找任何文件。和文件foo.jpg我保存在步骤1 /正显示出图像/ PNGMIME类型。

I'm not giving up, so the next logical step is to look for ANY file. And the file "foo.jpg" I saved in step 1/ is showing as "image/png" MIME type.

推荐答案

谜团解开。 这是一个功能！的jpgBuffer在

Mystery is solved. IT IS A FEATURE! The "jpgBuffer" in

cont.getOutputStream().write(jpgBuffer);

实际上包含PNG二进制数据。所以，即使我的应用程序指定的图像/ JPEGMIME类型，谷歌通过我的（我的用户）的数据探测后决定正确的MIME类型为图像/ PNG。还应当指出的是，它与一些延迟发生，使得调试过程更加神秘

actually contains PNG binary data. So even if my app specified "image/jpeg" MIME type, Google after snooping through my (my user's) data decided to correct MIME type to "image/png". It should also be noted that it happens with some delay, making the debugging process even more mysterious.

这篇关于图像/ JPEG＆QUOT; MIME类型从＆QUOT切换;到＆QUOT;图像/ PNG＆QUOT;的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！