Parameter "Value" disappears from ComboBox when Items property is set to a Switch statement with different Dataverse "Choices"

[larivibi]

Hello,

the title sums it up pretty much. 

Let me add some details to the actual process:
I have two Choices from Dataverse that I set to Items property of a ComboBox.

A Switch Statement determines the Dataverse's Choices to use with the Combobox, depending on a first choice from a DropDown.

What Works:

When I choose one of the two options from the DropDown, the ComboBox show the correct Choices according to the Switch statement mentionned earlier.

What doesn't work:

If I try to Concat the multiple values selected from the ComboBox into a Label, I get an error saying that the parameter Value doesn't exist. Thus I can't work with the SelectedItems of the ComboBox, even if the values appear correctly on the ComboBox.

If I remove the Switch Statement from the Items property of the comboBox and choose just on of the two Choices that were in the Switch Statement, I get the Value parameter back, and then I can Concat the selected Values from the ComboBox.

Any ideas on a workaround ?

I know I could use different ComboBoxes with the different Choices, but my goal if to use the least controls possible in my app, since the app is big a already needs a lot of controls.

Thanks in advance

[v-jefferni]

Hi @larivibi ,

Could you please share more details about your scenario? What formula are you using exactly?

Best regards,

[larivibi]

Ok.

I develop an Solution at the University where I work to manage the loads of the audiovisual equipment used by the students. In the solution, I am making two apps:

1. a first app to manage (CRUD) the equipment and the loans of the equipment.
2. a second app for the students to ask and borrow the material

My actual problem is with the first of the two apps.

In DavaVerse, I have two Choices columns (named: "PolarPattern" and "SamplingRate") that are associated to two columns (ModelPolarPattern and ModelSampleRate) in a Table called "Models". These two columns are used to filter the models, depending on the type of "Models" in the table. I also have another Choices column called "ModelsItemType" that is used in the Models table, but this one is used to filter the types of models (example : cameras, microphones,  ...).

In the app itself, I make a connection to the Models DataVerse table.

I want to optimize the app as much as possible by reusing controls and assigning them different usage, depending on the ItemType that is selected.
For convenience, I filter the models by "microphones" (ItemType) using a ComboBox (ItemTypeComboBox, which is a single choice column), a second ComboBox(Filter1ComboBox, which is a multiple choices column) is used to display the choices columns "PolarPattern" associated with microphones. Now if I select AudioRecorders from ItemTypeComboBox, the Filter1ComboBox will now display the PolarPattern Choices column.
To display the conditional Filter1ComboBox options, I use a Switch statement:

Switch(

Modeles.Selected.ModelsItemType.Value,

"Microphone",

Modeles.Selected.ModelPolarPattern.Value,

AudioRecorder,

Modeles.Selected.ModelSamplingRate.Value

).
So far, everything works as expected. The Filter1ComboBox show what it is supposed to show, depending on the selected ModelsItemType.

The problem is when I try to collect the information from the Filter1ComboBox by calling the Value attribute. PowerApps says that the Value parameter is not accessible from the Filter1ComboBox.
When I change the Filter1ComboBox Items to only one assiciated column (instead of using the Switch statement shown above), the Value parameter is now accessible.

I hope I clarified things. Again, thank you for your time

[v-jefferni]

Hi @larivibi ,

I can think of a workaround. Please try below steps:

OnChange of Modeles Combo box:

ClearCollect(varItems, Distinct(Switch(
Modeles.Selected.ModelsItemType.Value,
"Microphone",
Modeles.Selected.ModelPolarPattern.Value,
"AudioRecorder",
Modeles.Selected.ModelSamplingRate.Value
),"Value").Value
)

Items of Filter1ComboBox

varItems

And now you could try and use Filter1ComboBox.SelectedItems.Value.

Best regards,

[larivibi]

@v-jefferni 

Sorry, your suggestion does not seem to work either.

Let's simplify the scenario.
on a blank PowerApps page, create 1 ComboBox (ComboBox1) and one Toggle (Toggle1).

In DataVerse, create two Choices (multiple selection allowed on each of them) sets:

1. Choices of Colors (red, blue, green)
2. Choices of Fruits (banana, apple, orange)

Then, on ComboBox1 Items property, I put the following :
If(

    Toggle1.Selected.Value = true,

    Choices(Colors),

    Choices(Fruits)

)

So far, so good. 

Now, when I set the OnChange property of ComboBox1 as follows:

Notify(Concat(Self.SelectedItems;Value))

I get an error that says the term Value "does not exist".

But

when I go with a simple scenario (just one DataVerse Choices, lets say only the Colors), and I don't modify the OnChange property from the previous scenario, I can get the Value property.

Can someone try this on their side and confirm the error ?
Is there a way to achieve success with this, Or must I use a different ComboBox for each DataVerse Choice ? 

Thank you all for your time