A "Type Ahead" or "Searching" Dropdown control.

[Drrickryp]

I placed a textbox control over the window of the dropdown and set the color and fill to transparent, and set the clear button to “on”.  When the cursor is placed over the Textinput box both the text and fill of the control become opaque and will show the text that the Dropdown will use to search or filter.  When the cursor is moved off the Textinput box both the text and fill become transparent.  Depending on the datasource, use the Search function on the items property of the dropdown: Search(datasource, TextSearchBox.Text,"ColumnName")  or for SharePoint, use Filter(datasource,StartsWith(ColumnName, TextSearchBox.Text)). If the cursor is off the Textinput box, the control appears and functions as it normally does. Cursor over Textinput control

typing into Textinput control

Cursor off Textinput, control shows all items