widget-build.dart

@override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: <Widget>[ 
        imageURI == null
          ? Text('No image selected.')
          : Image.file(imageURI, width: 300, height: 200, fit: BoxFit.cover),

        Container(
          margin: EdgeInsets.fromLTRB(0, 30, 0, 20),
          child: RaisedButton(
            onPressed: () => getImageFromCamera(),
            child: Text('Click Here To Select Image From Camera'),
            textColor: Colors.white,
            color: Colors.blue,
            padding: EdgeInsets.fromLTRB(12, 12, 12, 12),
          )),

        Container(
          margin: EdgeInsets.fromLTRB(0, 0, 0, 0),
          child: RaisedButton(
            onPressed: () => getImageFromGallery(),
            child: Text('Click Here To Select Image From Gallery'),
            textColor: Colors.white,
            color: Colors.blue,
            padding: EdgeInsets.fromLTRB(12, 12, 12, 12),
          )),

        Container(
          margin: EdgeInsets.fromLTRB(0, 30, 0, 20),
          child: RaisedButton(
            onPressed: () => classifyImage(),
            child: Text('Classify Image'),
            textColor: Colors.white,
            color: Colors.blue,
            padding: EdgeInsets.fromLTRB(12, 12, 12, 12),
          )),     

        result == null
          ? Text('Result')
          : Text(result)       
    ]))
    );
  }