Power Apps - Building Power Apps

Combo box auto-unselects after selection

Like (1) Share

Report

Posted on 24 Mar 2025 18:43:30 by trogne

Hello,

I'm stuck on a app for months.

When a "Catégorie" is selected, my "Sujet" combo box auto-unselects after selection.

I've tried thousands of different things.

Here's my app attached.

You can test 2 ways :
- With the "Button" button : Start by selecting a "Catégorie", then hit the button. You'll see "TestSujet" briefly appearing on the 2 test labels, then getting cleared automatically.

- With the "SujetCombo" dropdown : Start by selecting a "Catégorie", then select a "Sujet". You'll see the dropdown selection automatically reverting back to blank.

Thanks for your help!

Categories:

General Questions

formdiscp_2025032...

All responses (6)

Answers (0)

Suggested answer

trogne 59 on 02 Apr 2025 at 14:01:03

Like (0)

Report

Combo box auto-unselects after selection

I finally got it working.

When I change "sujet", the corresponding "catégorie" updates.

But I already had code to update the "sujet" dropdown values when "catégorie" changes.

So, when the corresponding "catégorie" updates, it was then updating the "sujet" dropdown values and selecting a blank value.

I added a check so that the sujet dropdown does not change if it had a value initially.

This is the "Catégorie" combobox "OnChange" code :

If(

!gblIsUpdating,

Set(gblIsUpdating, true);

If(

!IsBlank(LookUp(gblSelections, ID = ThisItem.ID, Sujet)) &&

LookUp(Sujets, Sujet = LookUp(gblSelections, ID = ThisItem.ID, Sujet), Catégorie) <> Self.Selected.Value,

Patch(

gblSelections,

LookUp(gblSelections, ID = ThisItem.ID),

{Categorie: Self.Selected.Value, Sujet: ""}

),

Patch(

gblSelections,

LookUp(gblSelections, ID = ThisItem.ID),

{Categorie: Self.Selected.Value}

)

);

Set(gblIsUpdating, false)

)

And the "Sujet" combobox "OnChange" code :

If(

!gblIsUpdating && !IsBlank(Self.Selected.Sujet),

Set(gblIsUpdating, true);

Set(gblTempSujet, Self.Selected.Sujet);

Patch(

gblSelections,

LookUp(gblSelections, ID = ThisItem.ID),

{

Sujet: gblTempSujet,

Categorie: LookUp(Sujets, Sujet = gblTempSujet, Catégorie)

}

);

Set(gblIsUpdating, false);

Set(gblTempSujet, "")

)
ronaldwalcott 3,825 Super User 2025 Season 2 on 01 Apr 2025 at 21:27:57

Like (0)

Report

Combo box auto-unselects after selection

Can you state what the problem is and what you are trying to do without your app having to be installed.
trogne 59 on 01 Apr 2025 at 19:14:33

Like (0)

Report
Combo box auto-unselects after selection

I don't understand those phrases :

When Catégorie is being changed first in the control there will be OnChange Property check for that is there any variable is being set to the control . (for e.g Set(variablename,Catégorie.Selected.Value) and check in the target combo-box (Sujet) control Defaults / Default Selected Item Property is it referring to any such values.

Is the second combo box - Is cascading ? If yes also look for the Items property of the combo box have you written any filter condition accordingly.

What should I check first ?
MS.Ragavendar 3,056 Super User 2025 Season 2 on 26 Mar 2025 at 06:10:03

Like (0)

Report

Combo box auto-unselects after selection

@trogne,

Does the below analysis helped or still facing the challenge?
Suggested answer

MS.Ragavendar 3,056 Super User 2025 Season 2 on 25 Mar 2025 at 06:20:38

Like (0)

Report
Combo box auto-unselects after selection

@trogne,

Hi watch out the property of Default or Default Select Items in the combo-box.

If its form control you cannot reset the controls in the form like Reset(control/ datacard) which wont work you can only ResetForm() since you saying only with respect to the control.

When Catégorie is being changed first in the control there will be OnChange Property check for that is there any variable is being set to the control . (for e.g Set(variablename,Catégorie.Selected.Value) and check in the target combo-box (Sujet) control Defaults / Default Selected Item Property is it referring to any such values.

Is the second combo box - Is cascading ? If yes also look for the Items property of the combo box have you written any filter condition accordingly.

These are two things that you check and revert us back.

Please click Accept as solution if my post helped you solve your issue. This will help others find it more readily. It also closes the item
Michael E. Gernaey 46,507 Super User 2025 Season 2 on 25 Mar 2025 at 00:28:08

Like (1)

Report

Combo box auto-unselects after selection

Hi @trogne

I am going to quote and stop. You said. You've tried 1000s of things for what? What is the issue?

What is Category (no i don't install other people's apps from zips so you'll need to explain here)

Are these on a Form, a Gallery, just a Screen? When a Categories is selected, you are saying another Combobox clears its selected items? If so then somehow they are linked by data changing. So need to understand in more details that are missing.

Hello,

I'm stuck on a app for months.

When a "Catégorie" is selected, my "Sujet" combo box auto-unselects after selection.

I've tried thousands of different things.