title: How to Customize DropDown in flutter?
body: <p>In flutter i have tried to modify drop down like below <a href="https://i.stack.imgur.com/BBopX.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/BBopX.png" alt="enter image description here"></a></p>
  
  <p>i have tried using overlay with container but overlay is taking positioned from entire page. how to give positioned from previous widget to overlay</p>
  
  <pre><code>```import 'package:flutter/material.dart'; 
  List titles = ['a','b','c','d',];
  
  class sample extends StatefulWidget {
  @override
  CountriesFieldState createState() =&gt; CountriesFieldState();
  }
  
  class CountriesFieldState extends State&lt;sample&gt; {
  final FocusNode _focusNode = FocusNode();
    OverlayEntry _overlayEntry;
  
  final LayerLink _layerLink = LayerLink();
  
  OverlayEntry _createOverlayEntry() {
  RenderBox renderBox = context.findRenderObject();
  var size = renderBox.size;
  var offset = renderBox.localToGlobal(Offset.zero);
  return OverlayEntry(
      builder: (context) =&gt; Positioned(
            child: Container(
              height: 240,
              width: 320,
              child: Scaffold(
                body: Container(
                  margin: EdgeInsets.only(top: 8),
                  //color: Colors.red,
                  child: Column(
                    children: &lt;Widget&gt;[
                      new Expanded(
                          child: ListView.builder(
                        itemBuilder: (BuildContext context, int index) {
                          return new Container(
                            //width: (320/360)*screenWidth,
  
                            decoration: new BoxDecoration(
                                border: new Border.all(color: Colors.white),
                                color: Colors.white),
                            child: new ListTile(
                              //dense: true,
                              contentPadding: EdgeInsets.only(
                                  bottom: 0, left: 15, top: 0),
                              onTap: () {
                                _overlayEntry.remove();
                              },
                              title: new Text(
                                titles[index],
                                textAlign: TextAlign.left,
                                style: new TextStyle(
                                    fontSize: 15,
                                    fontFamily: "IBM Plex Sans Medium",
                                    fontWeight: FontWeight.w500,
                                    color: const Color(0xFF999aab)),
                              ),
                            ),
                          );
                        },
                        itemCount: titles.length,
                      )),
                    ],
                  ),
                ),
              ),
            ),
          ));
   }
  
   @override
   Widget build(BuildContext context) {
    return Scaffold(
    body: Column(
      children: [
        new InkWell(
            child: Align(
              alignment: Alignment.center,
              child: Container(
                margin: EdgeInsets.only(top: 100),
                decoration: BoxDecoration(
                  border: Border(
                    bottom: BorderSide(
                        width: 1.0, color: Colors.lightBlue.shade900),
                  ),
                  // color: Colors.red,
                ),
                height: 50.0,
                width: 300.0,
                child: Row(
                  mainAxisAlignment: MainAxisAlignment.spaceBetween,
                  children: &lt;Widget&gt;[Text("abc")],
                ),
              ),
            ),
            onTap: () {
              this._overlayEntry = this._createOverlayEntry();
             Overlay.of(context).insert(this._overlayEntry);
            })
      ],
    ),
  );
  }
   }```
  </code></pre>
  
  <p>i have used overlay concept to achieve this.
  Is there any other solution to achieve customized dropdown???</p>