flutter - BoxConstraints forces an infinite width

Question

I am getting an error when I add a row in a column. I am getting the following error:

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 

Also for reference here is my code:

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

Answer 1

If you are using TextField Inside a Row then you need to use Flexible or Expanded.

More details are given here in this answer.

https://stackoverflow.com/a/45990477/4652688