UIDocumentPickerViewController docx xlsx

IOS 调用 UIDocumentPickerViewController 选取文件：

"com.microsoft.word.doc",
"com.microsoft.word.docx",
"com.microsoft.excel.xls",
"com.microsoft.excel.xlsx"
"com.microsoft.powerpoint.​ppt"
"com.microsoft.powerpoint.​pptx",

设置了 docx， xlsx，​pptx   发现还是 只能选择 .doc  .xls  .ppt

无法选择 docx， xlsx，​pptx，均为灰色不可选择：

docx， xlsx，​pptx，均为灰色不可选择：

后来谷歌发现对应的格式不对：下面才是 正确的对应 格式

"com.microsoft.word.doc",
"org.openxmlformats.wordprocessingml.document",
"com.microsoft.excel.xls",
"org.openxmlformats.spreadsheetml.sheet"
"com.microsoft.powerpoint.​ppt"
"org.openxmlformats.presentationml.presentation",

文档地址：ios - Setting document extensions in UIDocumentPicker in swift - Stack Overflowhttps://stackoverflow.com/questions/52070937/setting-document-extensions-in-uidocumentpicker-in-swift/52071488