How to preserve focus on InputField after Print?

Question

If you press Enter in the example below it should become clear that test is being adding to the textbox instead of the current Notebook.

EventHandler[
 InputField["", String]
 , {"ReturnKeyDown" :> (
    SetSelectedNotebook[EvaluationNotebook[]];
    SelectionMove[EvaluationNotebook[], Notebook, All];
    NotebookWrite[EvaluationNotebook[], "test"]
    )}]

How might I force the text to be added to the Notebook instead of the other InputField?

EDIT: Ideally I am looking for a solution that doesn't involve removing focus from the InputField.

Answer 1

For version 9 or above, one can use CellPrint (or simply Print, as it is a specific case of CellPrint) which does not move the selection and thus preserves the focus on the InputField.

EventHandler[InputField["", String],
    {"ReturnKeyDown" :> CellPrint[Cell["test", "Output"]]}
]

---

Since the above code only works in v9, here is an equivalent with tedious selection-manipulation. First I set up the EventHandler as a cell, so that I can add a cell tag ("input") to it. This is necessary to be able to navigate the selection back (NotebookFind) after using Enter in the InputField, as one doesn't know how many extra cells will be generated. Using NotebookSelection however can only get us before the InputField, but not inside. To move the caret inside, a specific FrontEndToken is used ("MovePreviousPlaceHolder"). Perhaps someone knows a shorter method.

nb = EvaluationNotebook[];
CellPrint[ExpressionCell[
  EventHandler[InputField[Dynamic@test, String], {"ReturnKeyDown" :> (
      SelectionMove[nb, After, Notebook, AutoScroll -> False];
      NotebookWrite[nb, Cell[test, "Output"], AutoScroll -> False];
      NotebookFind[nb, "input", Previous, CellTags, AutoScroll -> False];
      SelectionMove[nb, Before, CellContents, AutoScroll -> False];
      FrontEndExecute@FrontEnd`FrontEndToken[nb,
            "MovePreviousPlaceHolder", AutoScroll -> False];
      SelectionMove[nb, After, Characters, AutoScroll -> False];
      )}],
   "Output", CellTags -> {"input"}]]