using showDialog flutter example

Example 1: showdialog with builder flutter

showDialog(
        context: context,
        builder: (BuildContext context) => new AlertDialog(
          title: new Text('Warning'),
          content: new Text('Hi this is Flutter Alert Dialog'),
          actions: <Widget>[
            new IconButton(
                icon: new Icon(Icons.close),
                onPressed: () {
                  Navigator.pop(context);
                })
          ],
        ));

Example 2: alertdialog flutter

showAlertDialog(BuildContext context) {

  // set up the button
  Widget okButton = FlatButton(
    child: Text("OK"),
    onPressed: () { },
  );

  // set up the AlertDialog
  AlertDialog alert = AlertDialog(
    title: Text("My title"),
    content: Text("This is my message."),
    actions: [
      okButton,
    ],
  );

  // show the dialog
  showDialog(
    context: context,
    builder: (BuildContext context) {
      return alert;
    },
  );
}