Set Powerapps screen based on a filter condition

[Anonymous]

Is it possible to display the default screen of powerapps based on logged-in user's email address?

I have condition like below.  If there is at least 1  record on the Sharepoint list's "EmployeeEmail" column value equal to logged-in user's email address, I want to display a different screen and if not, a different screen.  

Where and how can I handle that? 

CountRows(Filter('Equipment Return Tracker' ,EmployeeEmail=User().Email))

[TheRobRush]

originalDataSource was just an example text, if you have included it in your actual code it would fail. What is your collection made from, you need to base your formula on this, not the collection.

[jakub_podlaha]

Well obviously I would not use "originalDataSource" literarily in my code, that is not the point. As I wrote, your code will not work (even after renamed to propper screen and collection names) because of limitation on how StartScreen works. It throws following error: "Collections are not allowed in StartScreen." 

Like in the example below from my actual app. The collection name _Projects is higlighted in the formula with the error. Sorry the error text is in Czech, because of our corporate locale, but it is the forementioned error. The _Projects collection originates in the OnStart function. 

To quote the docs: Global variables and collections, including those created in OnStart, are not available in StartScreen. There are declarative alternatives for doing this that are on the way. For your feedback on this restriction, go to Power Apps community forum.

The blogpost mentioned earlier also states we should be able to sort things out using declarative global variables. But I am not aware of them being available in Power Apps as of now, that is two years later. 

So, as also mentioned in the blog, the only way to do this for now might be to re-enable the retired feature "Enable Navigate function in App.OnStart". 

Edit: 

I just figured, we can use App.Formulas for declarative variables. But since collections in these formulas can not be populated from flow calls. This won't help either - I still have to use OnStart for the navigation logic. 

[TheRobRush]

You still are not quite getting what I asked you to try.  originalDataSource needs to be replaced with the original source, not the collection you created. See below, I added annotations

If(

//Filter My Original Datasource (Sharepoint in Example) to only 
//Records with Rob in Title
 !IsEmpty(Filter(MainAreas, Title="Rob")),

//When I have records Titled Rob it goes here
actionChoice,

//If I delete those, and reload it goes here
loginScreen)

now you are not referencing a variable or a collection, but the datasource itself.

[jakub_podlaha]

Thank you for clearing this out. I did miss the original source therm there. The problem is that the collection is a result of a flow call, so that is not allowed either falling with "Behavioral function can not be used in non-behavioral property".  

I din't realize originally, that that makes all the difference. So I guess the new question is, how do I Navigate from a startscreen once I fetch the collection data using SomeFlow.Run() in OnStart? 

[TheRobRush]

Hmm, not sure since you are doing it via flow. How complex/large is the return that a flow is needed? And what is the flow like, step wise? We might have to fake it a bit.

[jakub_podlaha]

Thank you for your response. Well we might be drifting a bit off-topic here, but for completeness I'll just briefly describe the flows here: 

It is actually quite simple, it ollny fetches records of a SP list, with a twist though. I have a SP list containing list of "projects" with a column containing users of each of the projects - serving as project data (name, description, etc.) and access control list. This SP list shall not be directly accessible by app users - I do not want to have to add every app user to my SP page, neither them to edit it. So in order to provide users just with the data they need to run the app, I have one flow "On start flow" to fetch the projects filtered by their User().Email . And since users do not have access rights to this SP list, the flow calls another flow "Fetch projects flow" which has my (the app developer) access rights embeded (as opposed to using the users/callers access rights). I found this approach somewhere here on the forums. So OnStart -> Call my On Start flow -> Call my Fetch Projects by Email flow. 

I also want to create another SP list for "user settings". That one would persistently store values, user selected in dropdowns and text boxes all over the app. One of the settings would be the project, the user picked last time. So the app would open right, where the user left of last time, instead of having him pick the same project over and over again. 

That is the final goal: fetching two SP lists ("projects" and "user settings") and open the app on the right screen based on data in both. 

[TheRobRush]

I've looked into your reqs a bit now and think that likely the best scenario for you is to continue using your OnStart for navigation in your specific case. It's not that StartScreen replaced this and deprecated the other, it's just a declarative alternative. But if the conditions on which it is going to act are not present when the app starts then you would still want to use the OnStart. Basically start screen fires immediately upon opening the app. So it would not wait for a variable to be created. It would require info deep linked in the opening of the app, or something already existant like user info, etc. Or even a lookup coupled with With({}) to check a user list etc would work there (you could have a flow that runs every hr or so that looks up and updates default settings for every user in its own list for example, and skips any users that have used the app therefore now have their own personal choice settings. and then have the app StartScreen check that list)

Something like

With({userEmail: Office365Users.MyProfileV2().mail},
Switch(
        LookUp(listType, userEmail = Title, pageStart),
        "A", 'Page A', 
        "B", 'Page B'),
        'No Access'
      )
     )