Flutter - Textfield add new line

I try to make a TextField with keyboardType: TextInputType.visiblePassword to disable the predictive text but with that I can't go to a new line because it's a submit button. I try to add textInputAction: TextInputAction.newline but don't work too.

My TextField:

TextField(
     focusNode: myFocusNode,
     autocorrect: false,
     enableSuggestions: false,
     toolbarOptions: ToolbarOptions(copy: false, cut: false, paste: false),
     keyboardType: TextInputType.visiblePassword,
     textInputAction: TextInputAction.newline,
     autofocus: true,
     maxLines: null,
     controller: textEditor,
     decoration: InputDecoration(fillColor: Colors.grey[100])
))));

I add my textfield in a RawKeyboardListener and when user press "Enter" it's detect automatically.

RawKeyboardListener(
      focusNode: FocusNode(),
      onKey: (event) {
             if(event.isKeyPressed(LogicalKeyboardKey.enter)) {
                 int cursorPos = textEditor.selection.base.offset;
                 textEditor.text = textDebut + '\n' + textFin;
                 textEditor.selection = TextSelection.fromPosition(TextPosition(offset: cursorPos + 1));}},
child:TextField(
      focusNode: myFocusNode,
      autocorrect: false,
      enableSuggestions: false,
      toolbarOptions: ToolbarOptions(copy: false, cut: false, paste: false),
      keyboardType: TextInputType.visiblePassword,
      textInputAction: TextInputAction.newline,
      autofocus: true,
      maxLines: null,
      controller: textEditor,
      decoration: InputDecoration(fillColor: Colors.grey[100]),
      onChanged: (String text) {print(text);}))