No cursor is displayed when creating a tmp-inputfield in code

Questions & Answers
1

I created a tmp-inputfield in unity in code, but no cursor is displayed.

TMP_InputField tmpInputField = A.AddComponent<TMP_InputField>();
TextMeshProUGUI text = A.GetComponentInChildren<TextMeshProUGUI>();
tmpInputField.textComponent = text;
tmpInputField.textViewport = text.rectTransform;
2

You can’t create a TMP_InputField from scratch like this; you should use:
TMP_DefaultControls.CreateInputField(Resources resources).

This is how it's done in the editor. 
// TMPro.EditorUtilities.TMPro_CreateObjectMenu : 133
[MenuItem("GameObject/UI/Input Field - TextMeshPro", false, 2037)]
static void AddTextMeshProInputField(MenuCommand menuCommand)
{
    GameObject go = TMP_DefaultControls.CreateInputField(GetStandardResources());
    PlaceUIElementRoot(go, menuCommand);
}

You’ll just need to pass a Resources instance with Resources.inputField set to whatever you want the background sprite of the field to look like.