Hi @bcampbell13 :
I did a test, the function you mentioned really can not be achieved.I suggest you use a combination of controls to accomplish similar functions.For example:
1\My data source:
ClearCollect(
TestCollection,
{CodeNameClientName:"A",MatterClientName:"X"},
{CodeNameClientName:"B",MatterClientName:"Y"},
{CodeNameClientName:"C",MatterClientName:"Z"}
)
2\Add a toggle control(SetMatter_SelevtBy_Toggle)
3\Add a text input control(TextInput1)
OnSelect
Set(visible,true) /*visible is my custom variable*/
4\Add an arrow icon
OnSelect
Set(visible,!visible)
5\Add a list box(ListBox1)
Items
Filter(
TestCollection,
If(
SetMatter_SelevtBy_Toggle.Value,
StartsWith(
CodeNameClientName,
TextInput1.Text
),
StartsWith(
MatterClientName,
TextInput1.Text
)
)
)
OnSelect
Collect(TheResult,ListBox1.SelectedItems) /*TheResult is my custom collection*/
6\Add a gallery(Gallery3)
Items
TheResult
7\Add a label control into this gallery
Text
ThisItem.CodeNameClientName
8\Add a "X" icon into this gallery
OnSelect
Remove(TheResult,ThisItem)

Best Regards,
Bof