Why we can not use Navigate() in OnVisible

[Anonymous]

In my app I have a screen which acts as a loading screen and verifies that information is retrieved correctly from the server. 

For example here is a very simplified version of the OnVisible:

UpdateContext({LoadingText:"Searching for your name..."});
Set(
    _UserProfile,
    Office365Users.MyProfile()
);
If(
    !IsBlank(_UserProfile),
    Navigate(MainMenu_Screen,None),
    UpdateContext({LoadingText:"Failed to load your profile. Please restart the App"})
)

Having this function I get red line under Navigate which reads like this:

Navigate cannot be used here since it would always navigate away from this screen.

This error makes no sence since it would always navigate only if the IF condition is true. Can this limitation be removed please?

Work around

There is a simple workaround with using a button or any other control with OnSelect property and calling the Select(YourButton) to execute the Navigate() function.

For example, add a button and change its OnSelect to:

Navigate(MainMenu_Screen,None)

Now in the OnVisible property change your code to this:

UpdateContext({LoadingText:"Searching for your name..."});
Set(
    _UserProfile,
    Office365Users.MyProfile()
);
If(
    !IsBlank(_UserProfile),
    Select(Button1),
    UpdateContext({LoadingText:"Failed to load your profile. Please restart the App"})
)

Now it works as intended but you had to create some extra controls.

[Asimansari]

Hi @HadynM

Thanks so much for the suggestion and that would be the natural reaction to reach that control and delete it. It could also be done via the left side navigation area by right clicking the control.

But my problem was that the control contained a very very very complicated OnSelect property which I slowly built up in two-three weeks' time, I just couldn't risk deleting it.

However, I found a way. I just disconnected my internet after the screen loaded. The control started populating the collections without internet, and kept trying. I reconnected for a few moments and cleared the onvisible property of the screen. Saved the app in the same second and the problem was gone.

Anyways, it is always a pleasure in speaking with professionals, especially when someone takes time to help you out. I am an accountant by the way and very new to powerapps, but I am in love with the community here.

Many many thanks.

[biterbit]

I could not find a request to change this behaviour, so I raised a suggestion to do this: Allow conditional Navigate() function in screen's OnVisible property

[madmvx]

this was posted in 2017, now 2022 the error still happens

we need a solution, the validation is correct and don't going to enter in a loop, so what we can do????

If(
    Connection.Connected,
    If(
        IsEmpty(SOFR_col)
        ,
        Navigate(MainListLFR_Screen, Fade);
    )
)

[korebreach]

There is a "retired" feature you can turn on that allows Navigate() from the App OnStart.  However, "retired" features can go away anytime.

As mentioned above, the ability to do conditional navigation OnStart is most needed with "deep linking".  You probably know that you can pass parameters in a URL, which you can use in your app to alter what happens (such as what "mode" you want your app to run with, like starting on an edit screen or a specific record).  The problem with deep-linking is that it works great if you are using a web browser to access your app, but it won't work if you're using the "https://teams.microsoft.com/..." address (to launch your app inside Teams).

So, if you're looking for an elegant way to have your app navigate to "ScreenA" when played in your web browser (with your parameters), but navigate to "ScreenB" when you want it to load in Teams, the best way I've found is to configure it like this (assuming the parameters I'm passing are called, "tcs" and "qset"):

//First, get those parameters into global variables ("tcs" will become "vtcode" and "qset" will become "vName"

//App OnStart:

Set(vtcode,"");

If(!IsBlank(Param("tcs")) And IsBlank(vtcode), Set(vtcode,Param("tcs")),Set(vtcode,""));

If(!IsBlank(Param("qset")) And IsBlank(vName), Set(vName,Param("qset")),Set(vName,""))

//App StartScreen 

StartModeScreen

//StartModeScreen - blank screen (or add the same background you use elsewhere), except add a timer control.

//Timer Control Visible

false

//Timer Control AutoStart

true

//Timer Control Duration (in milliseconds)

1000

//Timer Control OnTimerEnd

If(IsBlank(vtcode), Navigate(ScreenA), Navigate(ScreenB))