相关疑难解决方法(0)

在列中添加行时出现错误。我收到以下错误：

I/flutter ( 6449): ??? EXCEPTION CAUGHT BY RENDERING LIBRARY ??????????????????????????????????????????????????????????
I/flutter ( 6449): The following assertion was thrown during performLayout():
I/flutter ( 6449): BoxConstraints forces an infinite width.
I/flutter ( 6449): These invalid constraints were provided to RenderAnimatedOpacity's layout() function 

我的代码也可供参考：

return new Scaffold(
      backgroundColor: whiteColor,
      body: new Column(
        children: <Widget>[
          imgHeader,
          lblSignUp,
          txtEmail,
          Row(
            mainAxisAlignment: MainAxisAlignment.start,
            children: <Widget>[
              txtFirstName,
              txtLastName
            ],
          ),
        ],
      ),
    );