Pictures can be integrated into a picture browser. For excel, if it is not the main function of your app, QuickLook should be enough. If you feel that QuickLook is not powerful enough, it is recommended to use a third-party software to open it. After all, what you mentioned here is an attachment. Since it is an attachment, there should be many different formats. If you are developing using a third party, you can use TTOpenInAppActivity, which is very convenient. If you plan to integrate it yourself, there are some open source tools in Github that can support processing.
You can use the Quick Look framework officially provided by Apple to preview these files, or you can use other apps to open and process the files through the provided interface. For details, please refer to this article of mine, short book --- Preview and share through UIActivityViewController
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Pictures can be integrated into a picture browser.
For excel, if it is not the main function of your app, QuickLook should be enough.
If you feel that QuickLook is not powerful enough, it is recommended to use a third-party software to open it. After all, what you mentioned here is an attachment. Since it is an attachment, there should be many different formats.
If you are developing using a third party, you can use TTOpenInAppActivity, which is very convenient.
If you plan to integrate it yourself, there are some open source tools in Github that can support processing.
https://github.com/search?l=&o=desc&q=excel+language%3AObjective-C&ref=advsearch&s=stars&type=Repositories&utf8=%E2%9C%93
You can use the Quick Look framework officially provided by Apple to preview these files, or you can use other apps to open and process the files through the provided interface. For details, please refer to this article of mine, short book --- Preview and share through UIActivityViewController
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