Flutter: Bottom sheet with TextField/TextFormField

You will have to provide a specific width to the TextField, simply provide width in your Container or wrap your Column in Expanded.

Solution 1

Container(
  width: 100, // do it in both Container
  child: TextField(),
),

Solution 2

Row(
  mainAxisAlignment: MainAxisAlignment.center,
  crossAxisAlignment: CrossAxisAlignment.center,
  children: <Widget>[
    Expanded( // wrap your Column in Expanded
      child: Column(
        children: <Widget>[
          Text('item 1'),
          Container(child: TextField()),
        ],
      ),
    ),
    Expanded( // wrap your Column in Expanded
      child: Column(
        children: <Widget>[
          Text('item 2'),
          Container(child: TextField()),
        ],
      ),
    ),
  ],
),