comboboxes - prevent duplicate selected value

[Anonymous]

Hello PowerApps community,

New to PowerApps here, I have 2 Comboboxes with identical items in a blank canvass screen. I would like to give user an error message if the selection in combobox2 is the same selection in combobox1.

Any help would be appreciated.

[rubin_boer]

hi @Anonymous 

Consider the following:

• datasource = __choices
• Combobox1 
• Combobox2
• label to show error

Perform the following

• ComboBox1 Items = __choices
• ComboBox2 Items = __choices
• label Text = "your message to user"
• label Visible = ComboBox2.Selected.Value in ComboBox1.SelectedItems

This will indicate a item selected in combobox 2 which exists in combobox1

Preventing the scenario completely consider

• ComboBox1 Items = __choices
• ComboBox2 Items = Filter(__choices, Not(Value in ComboBox1.SelectedItems)

Both scenario assume you will allow multiselect

Hope this helps,

R

[JR-BejeweledOne]

Are the ComboBoxes getting their items from a data source like a collection or did you manually type them into the items property?

[Abhilash_Swain]

Hi @Anonymous ,
Try like this.
On change property  of combobox 1,  clear and collect selected items. 
ClearCollect(test1,ComboBox1.SelectedItems.Value) [ Create a collection Test1.]

repeat the same for Combo box 2.

ClearCollect(test2,ComboBox2.SelectedItems.Value)

Below you can have a validation Label :- 
Concat(ForAll(test2, If(CountRows(Filter(test1,Value = ThisRecord.Value))>0,Concatenate(ThisRecord.Value,":-Duplicate Selected",Char(10)),Concatenate(ThisRecord.Value,":-Unique Selected",Char(10)))),Value)

Please give me a Thumbs up if I answered your question and mark it as a solution to help others.

Thanks

Abhi

[Anonymous]

The combobox items are coming from an excel data source, and I'm trying to avoid the user from making a duplicate selection.

[JR-BejeweledOne]

To build on the answer given by @rubin_boer , if you have manually typed your choices into the items property you can do the same thing like this:

Example:  Combbox1 Items ["Red", "Pink", "Blue", "Yellow"]

Combobox2 would be this:

Filter(["Red", "Pink", "Blue", "Yellow"], !(Value in ComboBox2.Selected.Value))

This will remove the selected item from the available choices in the second combo box

[rubin_boer · Accepted solution]

hi @Anonymous we have multiple people on this item for you. 

in my example you replace the following - highlighted in orange

Please make sure that you select the right column in the Fields

Consider the following:

Perform the following

• ComboBox1 Items = theNameOfYourExcelDataSource
• ComboBox2 Items = theNameOfYourExcelDataSource
• label Text = "your message to user"
• label Visible = ComboBox2.Selected.Value in ComboBox1.SelectedItems

This will indicate a item selected in combobox 2 which exists in combobox1

Preventing the scenario completely consider

• ComboBox1 Items = theNameOfYourExcelDataSource
• ComboBox2 Items = Filter(theNameOfYourExcelDataSource, Not(Value in ComboBox1.SelectedItems)

R

[prabeen]

the problem facing while using this solution 

If the user selected some people in first combo box . It will be removed from the second combo box

But If  the user again select the first combo box . And then when the user return the second combo box . If the 

selects  any option which was already selected . Again it will be counted as selected