Not possible to Set or UpdateContext to established variables from inside a DataCard in a Form Control?

[jzcase]

I have a pretty simple (I think) use case.

I want to show the user a different Edit Form on the same screen depending on a context variable, LogMode.

If LogMode="log", show Form1

If LogMode="mileage", show Form2

If LogMode="codes", show Form3

I can do this pretty easily with 3 buttons on the Screen with OnSelect=UpdateContext({LogMode:"whatever"}) and my forms appear or disappear as expected. Good! So I have a safety net.

BUT my preference would be to do this without buttons! It would be nice if the first DataCard of each form had a drop-down (pulling options from Dynamics365 Option Set), and the user's selection would UpdateContext({LogMode:"whatever"}) and make the proper form appear without thinking about it.

So I tried setting the OnChange property of the first DataCard of each Edit Form to something like:

If(DataCardValue12.Selected.Value="Travel",UpdateContext({LogMode:"mileage"}),if(DataCardValue12.Selected.Value="No Session",UpdateContext({LogMode:"codes"}),UpdateContext({LogMode:"log"})))

This code produced no errors, but it would not work! I kept a test label on the Screen showing me the current LogMode and it refused to change.

I also tried using a global variable instead but no difference in behavior.

So here's my main question: are Form controls "sandboxed" in some way so that they can't affect variables established outside of themselves? I see people in these threads seem to use variable declarations inside Form controls all the time, so I don't know what I'm doing wrong.

[v-xida-msft · Accepted solution]

Hi @jzcase ,

Do you create three separated Edit forms (Form1, Form2 and Form3) within your app, and want to display them based on the LogMode variable?

Based on the formula that you provided, I think there is something wrong with it. The DataCardValue12 could only represents the first Combo Box/Dropdown Data card within a single one Edit form, rather than that within each Edit form.

Based on the needs that you mentioned, I have made a test, if you want to display/hide your Edit forms based on the variable set up within your Edit form, I afraid that there is no way to achieve your needs in PowerApps currently.

As an alternative solution, you could consider add a Dropdown control (or ComboBox) outside the Edit form (within the screen) to achieve your needs. I have made a test on my side, please take a try with the following workaround:

Add a Dropdown control (Dropdown1) within your Edit screen, set the Items property to following:

["log", "mileage", "codes"]

Set the Visible property of the Form1 to following:

If(Dropdown1.Selected.Value = "log", true, false)

Set the Visible property of the Form2 to following:

If(Dropdown1.Selected.Value = "mileage", true, false)

Set the Visible property of the Form3 to following:

If(Dropdown1.Selected.Value = "codes", true, false)

Please take a try with above alternative solution, then check if the issue is solved.

Best regards,

[jzcase]

You're right: "DataCardValue12 could only represents the first Combo Box/Dropdown Data card within a single one Edit form, rather than that within each Edit form."

I have already implemented a similar solution to what you describe using buttons.

I hoped I could get past that limitation by having DataCardValue12.OnChange = if(DataVardValue12.Selected.Value="Travel",UpdateContext({LogMode:"mileage"}))

I take it from your response that I can't do that. Which is fine, I have an alternate solution.

But for my knowledge, could someone explain (or point me to an article that explains) why I can't use a Combo Box in each of my 3 forms to update a context variable that toggles their visibility?

[v-xida-msft]

Hi @jzcase ,

Just an update -- you could consider take a try to set up this variable in the OnChange property of first ComboBox Data card in each of your three Edit forms.

I have made a test on my side, please take a try with following workaround:

Set the OnChange property of the first ComboBox Data card (ComboBox1) in your Form1 to following:

If(
  ComboBox1.Selected.Value = "log", 
  Set(LogMode, "log"), 
  ComboBox1.Selected.Value = "mileage",
  Set(LogMode, "mileage"),
  ComboBox1.Selected.Value = "codes",
  Set(LogMode, "codes")
)

Set the Visible property of the Form1 to following:

If(LogMode = "log", true, false)

Set the OnChange property of the first ComboBox Data card (ComboBox2) in your Form2 to following:

If(
  ComboBox2.Selected.Value = "log", 
  Set(LogMode, "log"), 
  ComboBox2.Selected.Value = "mileage",
  Set(LogMode, "mileage"),
  ComboBox2.Selected.Value = "codes",
  Set(LogMode, "codes")
)

Set the Visible property of the Form2 to following:

If(LogMode = "mileage", true, false)

Set the OnChange property of the first ComboBox Data card (ComboBox3) in your Form3 to following:

If(
  ComboBox3.Selected.Value = "log", 
  Set(LogMode, "log"), 
  ComboBox3.Selected.Value = "mileage",
  Set(LogMode, "mileage"),
  ComboBox3.Selected.Value = "codes",
  Set(LogMode, "codes")
)

Set the Visible property of the Form3 to following:

If(LogMode = "codes", true, false)

In addition, when you load your Edit form, set one of your three Edit forms as the Default display form. Please take a try with the following workaround:

Set the OnVisible property of the Edit screen to following:

Set(LogMode, "log")

Best regards,

[v-xida-msft]

Hi @jzcase ,

Have you solved your problem?

If you have solved your problem, please go ahead to click "Accept as Solution" to identify this thread has been solved.

Best regards,