autofocus property
final
Whether this text field should focus itself if nothing else is already focused.
If true, the keyboard will open as soon as this text field obtains focus. Otherwise, the keyboard is only shown after the user taps the text field.
Defaults to false.
Implementation
// See https://github.com/flutter/flutter/issues/7035 for the rationale for this
// keyboard behavior.
final bool autofocus;