UWP command line arguments

Hello,

I am wondering if there is a way to modify the generated project when building a UWP app to:
-call it easily through command line
-pass custom arguments that can be used in the default loaded scene (i.e. set the text of a UI element to be the first argument)

I 've managed to call my app through the CMD with an Alias, but I cannot parse any extra arguments after that and pass then to Unity. I 'm using Environment.GetCommandLineArgs(); in my scene, but I don't think that is the right way, especially when trying to pass the arguments through the UWP project from CMD.

Any suggestions?
Thanks

 

But how can you use the values set via the AppCallbacks? How can the developer access them in a Unity Script?

Thanks

 

Oh its that easy! Works like a charm! Thanks a lot

 

Though, might there be an issue with quoted strings in the arguments string? Something like this arrives with backslashes in front of the double quotes in the Environemen.GetCommandLineArgs:

Code (CSharp):

1. Platform::String^ cmdLineArgumentents = LR"(-File "E:\projects\Unity\deploy\build\bin\x64\Debug\AppX\Data\file.txt")";

 

I tested it with a single argument string:

Code (CSharp):

1. Platform::String^ cmdLineArgumentents = LR"(-File "E:\projects\Unity\deploy\build\bin\x64\Debug\AppX\Data\file.txt")";

Environment.GetCommandLineArgs contained this:

Code (CSharp):

1. -File \"E:\projects\Unity\deploy\build\bin\x64\Debug\AppX\Data\file.txt\"

And I wonder wether the leading back slashes in front of the double quotes are correct and if not, what the reason is, that we see it here.

 

Like this: https://docs.unity3d.com/Manual/windowsstore-commandlinearguments.html

 

I'll try that! Thanks a lot!

 

So, I must be missing something.

• Isn't the App.cpp file auto generated and therefore going to get overwritten when the player is built from within the Editor? If I customize it, aren't I going to lose those changes.
• This looks like the arguments are hard coded into the AppCallbacks constructor and can't be changed at run time anyway. So, the solution here is to hard code a path to a file and read the arguments from there?
  • Why would I use this approach over just processing a setup file in a monobehaviour? (Assuming I'm not using any default player parameters that are processed by the unity engine.)

Mike

 

Thank you. I agree with your statements in part. I'm working on a general purpose application that can be configured at runtime to plot user specific data in 3D. I use command line parameters to...

1. Load a configuration file (specified on the command line) that contains JSON settings to data sources and plot configurations.
2. Force the engine to use a particular vrmode (or none) from the standard engine cmd line parameters.

I'm not very familiar with the UWP development, so if you have suggestion, I'd appreciate them.

My best ideas are

1. Create a new file type for my plot configuration files and make a file association so that the app will launch automatically. Haven't figured out how to get the file selected. (Is this a protocol launch?)
2. Create an application setup file that will have to be modified manual to indicate the VR mode, and will reside in a known location. This, I think, is what this thread is suggesting.

Thanks for the tips.

 

The same app is going to be used on a variety of data sets. For "canned" visualizations where an analyst has already pre-configured what he wants to see, it's usually launched from a batch file or button on menu that has been configured to launch the application with a particular configuration file.

During development, the analyst will run a data set against a variety of configurations (in desktop, a HMD, and in a CAVE (stereo VR), mode). It's just easier to pass cmd line parameters or create batch files to do that.

I'm not against an interactive UI. It just takes longer for the user to load the visualization and is more difficult to automate. And, I know it's changing, but Unity's UI support just doesn't work very well in VR yet.

I think the best compromise I'm finding is to associate my app with a new file type for the visualization configuration files and given them a unique extension. I can configure Unity to launch the app on that type, but I don't know how to get the file that caused the launch from within a Monobehavior yet.

 

Thanks. Probably won't get to it until next week, but I'll take a look.

 

Finally got a chance to take a look at the code you posted. Didn't get it working, but did realize that on file activation, the file is contained WSA.Applicaiton.argument member.

https://docs.unity3d.com/ScriptReference/WSA.Application-arguments.html

However, I'm getting a directory not found exception on a path that is perfectly valid.

DirectoryNotFoundException: Could not find a part of the path "C:\Users\mew9\Desktop\Visualization\Config.kpl".
at System.IO.FileStream..ctor (System.String path, System.IO.FileMode mode, System.IO.FileAccess access, System.IO.FileShare share, System.Int32 bufferSize, System.Boolean anonymous, System.IO.FileOptions options) [0x00000] in <00000000000000000000000000000000>:0
at System.IO.StreamReader..ctor (System.String path, System.Text.Encoding encoding, System.Boolean detectEncodingFromByteOrderMarks, System.Int32 bufferSize, System.Boolean checkHost) [0x00000] in <00000000000000000000000000000000>:0
at System.IO.StreamReader..ctor (System.String path) [0x00000] in <00000000000000000000000000000000>:0
at System.IO.File.ReadAllText (System.String path) [0x00000] in <00000000000000000000000000000000>:0

Thought it might be this issue.
https://issuetracker.unity3d.com/issues/uwp-il2cpp-file-dot-exists-method-returns-false

So, I enabled the app's file system privledge, and I added broadFileSystemAccess to the manifest per this article
https://docs.microsoft.com/en-us/windows/uwp/files/file-access-permissions
(The editor is complaining about Capability being an invalid element in the restricted capabilities namespace.)

If it's a security problem, I'm surprised by the DirectoryNotFound exception. Can I use the FileStream class in UWP if the app has the proper permissions?

 

I'd rather do it the right way, so thank you for pointing me to the FutureAccessList. It seems strange to me that an application would be able to give itself access to a file/folder this way. And, when I tried to add access to the Application.arguments file, I got an access violation anyway. (Maybe I need to add all the folders in the path as well?)

The examples I see all use a picker, but I'd really want the user to be able to just double click on a file and go.

using System;

using System.Collections;

using System.Collections.Generic;

using System.IO;



using UnityEngine;



#if ENABLE_WINMD_SUPPORT && UNITY_WSA

using Windows.Storage;

using Windows.Storage.AccessCache;

#endif



using Kraken;



public class UPWLoadTest : MonoBehaviour

{

   // Start is called before the first frame update

    void Start()

   {

   }



   private void Update()

   {

       if (Input.GetKeyDown(KeyCode.Space))

           Load();

   }



   // Start is called before the first frame update

    async void Load()

   {

#if ENABLE_WINMD_SUPPORT && UNITY_WSA

       Debug.Log( UnityEngine.WSA.Application.arguments );

               

       string prefix = "File=";

       string wsaArgs = UnityEngine.WSA.Application.arguments.Trim();

       if ( wsaArgs.Length > 0 && wsaArgs.StartsWith(prefix) )

       {

           string path = wsaArgs.Substring(prefix.Length);

           StorageFile file = await StorageFile.GetFileFromPathAsync(path);

           StorageApplicationPermissions.FutureAccessList.Add( file );

       

           Debug.Log("Loading: " + path );

           string text = File.ReadAllText(path);

           

           Debug.Log("text: " + text );

       }

#endif

   }

}

 

Ok. But, I don't have access to the StorageFile object from the ActivationArgs on the C# side, right?
It doesn't exactly solve my problem anyway. The config file from the file activation is going to contain paths to data files for loading. I'm trying hard to avoid the file/folder pickers as the app will be run in VR CAVEs and HMDs. And, the data and config files are auto generated for visualization (as often as daily). If I add a StorageFolder to the FutureAccessList, will the contents and subfolders also be authorized? And, future additions to the folder? It would be acceptable to authorize a folder once using the picker strategy.

The other option I stumbled upon here is to add the ALL_APPLICATIONS_PACKAGES group to the folder(s) where data is stored. It's more work to set up, but looks like it might be more convenient long term.

https://www.mr-kg.com/uwp-file-access/

Appreciate the advice. My entire UWP experience is with Unity, so I'm out of my element.

 

I hate to ask, but is there a Unity/UWP sample around that shows how to access local files (with or without the FutureAccessList)? I get a COM exception just trying to open the FileOpenPicker. (Wrong thread, maybe?)

Update:
https://forum.unity.com/threads/how-to-show-native-file-picker.381528/

Update:
Nope. Still getting a COM exception.

    async void Start()

    {

#if WINDOWS_UWP

        UnityEngine.WSA.Application.InvokeOnUIThread( OpenPicker, true);

#endif

    }



#if WINDOWS_UWP

    async static private void OpenPicker()

    {

        Debug.Log("creating file picker");

        var filePicker = new FileOpenPicker();

        Debug.Log("picking single file");

        StorageFile file = await filePicker.PickSingleFileAsync();

        Debug.Log("file pick done");

    }

#endif

 

(Sigh) You're right.
I'd already been using the MS sample you highlighted as a guideline, but wanted to open it to all file types. It would appear that the FileTypeFilter is less optional than I'd understood. I still need to figure out how to use a picker to give access to a specific (pre-known) file, but at least I'm on the right track.

Appreciate the advice. Including a working example here for others. (Note: I know I've got a concurrency issue related to accessing the text member on both the UI and Applicaiton thread. This was just proof of concept and I'll need to invoke a method to read the file on the application thread.)

Mike

Code (CSharp):

1.  
2. using System;
3. using System.Collections;
4. using System.Collections.Generic;
5. using UnityEngine;
6.  
7. #if WINDOWS_UWP
8. using Windows.Storage;
9. using Windows.Storage.AccessCache;
10. using Windows.Storage.Pickers;
11. #endif
12.  
13.  
14. public class ShowFile : MonoBehaviour
15. {
16.     private string text = null;
17.  
18.     // Start is called before the first frame update
19.     async void Start()
20.     {
21. #if WINDOWS_UWP
22.         UnityEngine.WSA.Application.InvokeOnUIThread( OpenPicker, false);
23. #endif
24.     }
25.  
26. #if WINDOWS_UWP
27.     async private void OpenPicker()
28.     {
29.         var picker = new Windows.Storage.Pickers.FileOpenPicker();
30.         //picker.ViewMode = Windows.Storage.Pickers.PickerViewMode.Thumbnail;
31.         //picker.SuggestedStartLocation = Windows.Storage.Pickers.PickerLocationId.PicturesLibrary;
32.         picker.FileTypeFilter.Add(".kpl");
33.         //picker.FileTypeFilter.Add(".jpeg");
34.         //picker.FileTypeFilter.Add(".png");
35.  
36.         Windows.Storage.StorageFile file = await picker.PickSingleFileAsync();
37.         if (file != null)
38.         {
39.             // Application now has read/write access to the picked file
40.             Debug.Log( "Picked photo: " + file.Name );
41.  
42.             text = await Windows.Storage.FileIO.ReadTextAsync(file);
43.         }
44.         else
45.         {
46.             Debug.Log( "Operation cancelled." );
47.         }
48.     }
49. #endif
50.  
51.     void OnGUI()
52.     {
53.         GUILayout.Label( "Hello World!" );
54.  
55.             if ( text != null )
56.                 GUILayout.Label(text);
57.  
58.         GUILayout.Label("Bye");
59.     }
60. }
61.  

 

Hi! So, how to make "Open As" working with UWP + Unity? Is it even possible?