Form Combo Box

PDF Studio is capable of creating Combo Boxes (drop down fields). Combo Boxes are used to allow users to select an option from a list of available text options from a drop down menu. If set, users can also be allowed to enter their own custom value.

Creating Combo Boxes

  1. Start the Form Editing Mode by going to Forms > Create/Edit Form on the menu or use the shortcut keys Ctrl + Shift + M (⌘ + Shift + M on Mac). This will open up the Form Field Editor Toolbar.
  2. Click on the Combo Box button located on the tool bar. The cursor will then change to show a preview of the field
  3. Using the mouse move to the location you want to place the field and then click to place the field or click and drag to create a custom field size.
  4. The Combo Box Properties dialog will then be displayed so that you can add the options to the list as it will initially be blank.
  5. Click on the Options tab
  6. Type in each of the options that you wish to add in the Item field and then click on Add or press Enter on your keyboard. Your new item will be displayed in the list below. Continue adding all the items that you need and once complete click on OK to set the list options
  7. Repeat steps 1-6 to create as many fields as you need
  8. To finish placing Combo Boxes press Esc or click on the button on the toolbar

Combo Box Properties

To access the Combo Box properties right click (Mac: Ctrl + Click) on the field and choose Properties in the mouse menu or click on the edit button on the Mini Toolbar. The Combo Box contains the following property settings.


Name - The name of the field

Tooltip - The tip that is shown when the mouse is hovered over the field


Font - Sets the font of the text

Size - Sets the font size of the text

Text Color - Sets the text color

Border Color - Sets the color of the border

Line Width - Sets the width of the border line

Fill Color - Sets the fill color

Style - Sets the style for the border line (i.e. dotted, dashed, cloud, etc...)

Save as default - When checked this will make the selected style settings the default for any new Combo Boxes going forward


Rotation - Sets the field rotation in 90 degree increments

Required - When checked will display a red outline on the field letting them know the field is required

Visibility - Sets one of four visibility options for the field

      • Show: the default setting makes the field visible
      • Hide: hides the field from being displayed when viewing the document
      • Show/Do not print: shows the field but will not print the field or it's values
      • Hide/Print: hides the field but the field and its value will be printed

Read Only - Makes the field uneditable and will just display the value currently set in the field

Locked - When checked prevents the following on the field: being moved or resized, editing appearance properties, & deleting the annotation.


Item - Type the name of the item you would like to add to the combo list

Add - Adds the text in the Item field to the combo list

Export Value - The value to be exported when the Item is selected in the combo box

Default - When checked, this will make the selected option the default value of the field. This is the value that will be displayed if the field is empty or when Resetting Form Fields

Delete - Deletes the selected items from the list

Move Up - Moves the selected item up the list

Move Down - Moves the selected item down the list

Allow Custom Text - When checked, allows the user to enter custom text in the field. Otherwise, the user must select an option

Sort Items - Will alphabetically sort all of the items in the list

Note: This cannot be undone after it has been sorted you will need to manually resort the items

Commit Selected Immediately - When using Form Field Calculations this will submit the value to the calculation (if set) immediately. Otherwise, it will need to be triggered using another method.

Spell Check - When checked enables the "Spell Check" property of the field. When the Spell Check property is set, if the PDF viewer/editor supports spell checking it will be enabled only on fields with this property set.

Note: This option will only be enabled if "Allow Custom Text" is enabled.


Sets the formatting rules for the field based on the option and settings selected. When a format is selected the formatting will be enforced using JavaScript and the user will not be able to enter any other value other then what is set in the rules. See Field Formatting for additional details.

None - Default value, sets no formatting rules and any text can be entered into the field

Number - Sets the field to only accept numbers based on the settings selected

Percentage - Sets the field to display a percentage based on the settings selected

Date/Time - Sets the field to only accept date, time, or date-time values based on the settings selected.

Note: When a date or date-time setting is selected when viewing the document PDF Studio will display a calendar button on the field. This button will allow users to select a date using a calendar picker instead of typing in the field if they wish.

Other - Allows you to select from a list of common predefined field formatting rules

Custom - Allows you to create your own custom formatting rules using the supported PDF Form JavaScript


Sets the calculation rules for the field based on the option and settings selected. When a calculate is set it will be enforced using JavaScript. See Form Field Calculations for additional details

No Calculation for this field - Default value, sets no calculation rules and any text can be entered into the field

Field value has simple calculation - When selected allows you to set a single math calculation on either all or a selection of fields.

This field has a custom calculation - When selected you will need to use Form JavaScript to create custom calculations

Simple Field Notation - When checked this allows you to use simple calculation commands (+ - / *)instead of JavaScript. See Form Field Calculations for additional details


Sets validation rules for the field based on the option selected. Validation is different from format in that validation restricts what values are allowed to be entered into the field

No validation for this field - Default value, sets no validation rules and any value can be entered into the field

Field values has a range - Only available when Format is set to a Number or Percentage.

This field has custom validation - When selected you will need to use Form JavaScript to create custom validations


The Action Panel displays a list of the current actions associated with the field. Actions can be added, edited, or deleted using the buttons below the actions list.

Add - Adds a custom Form Field Actions from a list of available actions.

Edit - Edits the currently selected action from the list

Remove -  Removes the currently selected action from the list