fluttertoast

# add this line to your dependencies
fluttertoast: ^8.2.2

import 'package:fluttertoast/fluttertoast.dart';

Fluttertoast.showToast(
        msg: "This is Center Short Toast",
        toastLength: Toast.LENGTH_SHORT,
        gravity: ToastGravity.CENTER,
        timeInSecForIosWeb: 1,
        backgroundColor: Colors.red,
        textColor: Colors.white,
        fontSize: 16.0
    );

Fluttertoast.cancel()

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="center_horizontal"
    android:layout_marginStart="50dp"
    android:background="@drawable/corner"
    android:layout_marginEnd="50dp">

    <TextView
        android:id="@+id/text"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="#CC000000"
        android:paddingStart="16dp"
        android:paddingTop="10dp"
        android:paddingEnd="16dp"
        android:paddingBottom="10dp"
        android:textStyle="bold"
        android:textColor="#FFFFFF"
        tools:text="Toast should be short." />
</FrameLayout>

MaterialApp(
    builder: FToastBuilder(),
    home: MyApp(),
    navigatorKey: navigatorKey,
),

FToast fToast;

@override
void initState() {
    super.initState();
    fToast = FToast();
    // if you want to use context from globally instead of content we need to pass navigatorKey.currentContext!
    fToast.init(context);
}

_showToast() {
    Widget toast = Container(
        padding: const EdgeInsets.symmetric(horizontal: 24.0, vertical: 12.0),
        decoration: BoxDecoration(
        borderRadius: BorderRadius.circular(25.0),
        color: Colors.greenAccent,
        ),
        child: Row(
        mainAxisSize: MainAxisSize.min,
        children: [
            Icon(Icons.check),
            SizedBox(
            width: 12.0,
            ),
            Text("This is a Custom Toast"),
        ],
        ),
    );


    fToast.showToast(
        child: toast,
        gravity: ToastGravity.BOTTOM,
        toastDuration: Duration(seconds: 2),
    );
    
    // Custom Toast Position
    fToast.showToast(
        child: toast,
        toastDuration: Duration(seconds: 2),
        positionedToastBuilder: (context, child) {
          return Positioned(
            child: child,
            top: 16.0,
            left: 16.0,
          );
        });
}

GlobalKey<NavigatorState> navigatorKey = GlobalKey<NavigatorState>();

FToast fToast = FToast();
fToast.init(yourNavKey.currentContext!);

// To remove present shwoing toast
fToast.removeCustomToast()

// To clear the queue
fToast.removeQueuedCustomToasts();