Flutter TextFormField onChanged event

Question

我想使用TextFormField构建自动完成功能，我不知道如何为TextFormField创建OnChanged事件。我的要求是将文本字段包含一些文本，如果用户编辑该文本，则文本字段应表现为自动建议。

Answer 1

Are you wrapping TextFormField in a FormField widget? If not, I suggest to use just TextField which has an onChange property

Edit: To set an initial value you can add a TextEditingController and asign it to the TextFormField

TextEditingController _controller = TextEditingController();

then in initState() you can do

_controller.text = 'Initial Value'

Answer 2

Lucky for us the onChanged option in the TextFormField is already available. If you update flutter and doesn't work just go to the text_form_field.dart file by clicking on the Widget TextFormField + command/control and modify the text with code in the link: text_form_field.dart