Yet another "No apps can perform this action"

[shielrp]

Description of the bug

A small subset of our users, seemingly only on Android, receive the "No apps can perform this action" message when trying to use the function that invokes PickFile. The filetype being selected is a JSON file. We've been unable to reproduce the issue in-house.

Platform specs

Please provide the following info if this is a Unity 3D repository.

• Unity version: 2020.3.27f1
• Platform: Android, possibly iOS
• How did you download the plugin: Asset Store

Additional info

Here is some relevant parts of the code in question.

var allowedTypes = new string[] { NativeFilePicker.ConvertExtensionToFileType("json") };

var permission = NativeFilePicker.PickFile((pth) =>
{
   //callback content
}, allowedTypes);

It's worth mentioning that this is happening with version 1.29 of NativeFilePicker. We are working to release an update that upgrades the package to 1.30, but have not been able to test this issue in that update as of yet.

[yasirkula]

I don't think 1.30 will help with this issue. You can try hardcoding "application/json" as allowedTypes' value rather than using ConvertExtensionToFileType to see if that function fails but I don't think that's the culprit. I wonder if any other file type like "txt" work correctly on those devices. Perhaps they are rooted or uncommon devices with no file browser installed which thus don't have the functionality to pick files with that nonexisting file browser.

PS. You can also call this function in Awake/Start to see if it helps:

#if UNITY_ANDROID
using( AndroidJavaClass ajc = new AndroidJavaClass( "com.yasirkula.unity.NativeFilePicker" ) )
	ajc.SetStatic<bool>( "UseDefaultFilePickerApp", true );
#endif

[shielrp]

Thanks a ton, I appreciate the leads! I'll add that code to the game, and I'll see if getting a decent file browser on a users phone will solve the issue.

[shielrp]

I ended up resolving this issue by adding NativeFilePicker.ConvertExtensionToFileType("txt") to the allowedTypes array, and by changing future exported files to have a .txt extension. The picker now shows on affected phones, but is unable to select .json files. If the files are changed to have a .txt extension, they are selected fine.

I could have done this without changing the exported file extension, but I'm just trying to head off having to provide a solution to folks in the future.

Thanks for the insight, I couldn't have fixed it without you! Or built this feature at all for that matter!

Edit: I should mention that installing a 3rd party file manager onto an affected user's phone did not seem to have any effect on the issue.

[yasirkula]

Thank you for sharing your findings! Did you try hardcoding "application/json" as allowedTypes before switching to txt?

[shielrp]

I didn't, sorry. I'll add that in a future release and see if I can test it for you.

[marcusx2]

I have the same issue on my Android, it's a Samsung S8. My allowed types is just

var allowedTypes = new string[] { NativeFilePicker.ConvertExtensionToFileType("*") };

I expected it to open the same menu as WhatsApp when you tap on the attachment icon, where you can choose an app to get the file you want ;_;.

[yasirkula]

Try var allowedTypes = new string[] { "*/*" }; instead.

[marcusx2]

Yes this worked. On the Unity editor on macOS, I couldn't find an allowed type for any file though. It's ok because it's only in the editor now though, it works if I use image/* for testing purposes. But if you know an allowed type that works for any file in the editor on macOS let me know.

[yasirkula]

I don't think there is a such filter on either Mac or Windows :/

[marcusx2]

@yasirkula What's the allowed type for any file on iOS? I tried the "/", it works on Android, but on iOS the files show up but I can't select them..

[yasirkula]

@marcusx2 I'd set it to the following array but I haven't tried it: new string[] { "public.item", "public.content" }