How to give a place holder in dropdown/select from OutsystemsUIWeb.

Please see the following link :


Just as there is a 'primary' Place Holder in the combo box above.

I also tried the following code in Advanced Format of DropDownSelec as seen in the following screenshott:

Please help.


Manthan Shah.


To achieve something like this:

You have to provide a special list value on the combo box that you have on the screen.

0 as Value 1 and Option 1 as Please select a color

To avoid allowing the user to submit an invalid option you may want to use one of the following options(or both):

1. Make sure the mandatory value of the combo box is set to true and if you have a button with the validation type "Client and Server"

This will make a client side validation and if the value of the variable is zero(variable has to be of type integer/long integer/identifier) it will raise an error near the combo box:

2. Validate on the server side if the combo box variable is equal to zero. If so, you could raise an error "Please select a valid color"

Kind regards,

Márcio Menezes

Hi Márcio Menezes,

According to your method in the combo box we can select 'Please Select A Color' also from the combo box.

But as seen in the link below:


We can't select primary and also can't see primary in the combo box list but we can select other items from combo box. 

I have to implement the behavior of combo box like the above link.


Manthan Shah.

Hi Manthan,

Primary is a option in that combobox. Is at the end of the options. You can try and use a list box. Because placeholders only work on multiple select combobox.