flutter - Flutter TextField与 Controller 根本不更新该字段

Question

我以为我拥有这项权利，但显然有些问题了。简单文本字段，默认文本由 Controller 设置为newUser['firstName']。 newUser的类型为Map<String, Dynamic>

TextField(
    decoration: InputDecoration(labelText: 'First Name'),
    controller: TextEditingController(text: newUser['firstName']), // currently set to "Garrett"
    onChanged: (text) {
        print('TEXT: $text'); // only gives the current value plus the last letter hit, ex. 
        "Garrettr", "Garrettf", etc.

        setState(() {
            newUser['firstName'] = text;
        });

        print('FIRST NAME: ${newUser['firstName']}'); // same as text
    },
),

没有错误，但是当我在字段中键入更改文本时，什么也没有发生，并且 newUser['firstName']将等于“Garrette”或“Garrettr”等。如您在代码中看到的那样，通过 text传入的 onChanged似乎并不是的，虽然不确定我在做什么错。

Answer 1

在TextField初始化类似final TextEditingController anyThing = new TextEditingController();之类的代码之前，先检查一下代码

现在获取新文本集newUser['firstName'] = anyThing.text
试试这个，让我知道您是否需要进一步的帮助。

因此，整个过程将是:

final TextEditingController anyThing = new TextEditingController();
TextField(
        decoration: InputDecoration(labelText: 'First Name'),
        controller: anyThing, // currently set to "Garrett"
        onChanged: (text) {
          print('TEXT: $text'); // only gives the current value plus the last letter hit, ex.

          setState(() {
          newUser['firstName'] = text;
          });

          print('FIRST NAME: ${newUser['firstName']}'); // same as text
        },
      ),