dart
import
'package:flutter/material.dart'
;
import
'package:flutter_test/flutter_test.dart'
;
void
main
() {
testWidgets
(
'Add and remove a todo'
, (tester)
async
{
// Build the widget.
await
tester.
pumpWidget
(
const
TodoList
());
// Enter 'hi' into the TextField.
await
tester.
enterText
(find.
byType
(
TextField
),
'hi'
);
// Tap the add button.
await
tester.
tap
(find.
byType
(
FloatingActionButton
));
// Rebuild the widget with the new item.
await
tester.
pump
();
// Expect to find the item on screen.
expect
(find.
text
(
'hi'
), findsOneWidget);
// Swipe the item to dismiss it.
await
tester.
drag
(find.
byType
(
Dismissible
),
const
Offset
(
500
,
0
));
// Build the widget until the dismiss animation ends.
await
tester.
pumpAndSettle
();
// Ensure that the item is no longer on screen.
expect
(find.
text
(
'hi'
), findsNothing);
});
}
class
TodoList
extends
StatefulWidget
{
const
TodoList
({
super
.key});
@override
State
<
TodoList
>
createState
() =>
_TodoListState
();
}
class
_TodoListState
extends
State
<
TodoList
> {
static
const
_appTitle =
'Todo List'
;
final
todos = <
String
>[];
final
controller =
TextEditingController
();
@override
Widget
build
(
BuildContext
context) {
return
MaterialApp
(
title: _appTitle,
home:
Scaffold
(
appBar:
AppBar
(
title:
const
Text
(_appTitle),
),
body:
Column
(
children: [
TextField
(
controller: controller,
),
Expanded
(
child:
ListView
.
builder
(
itemCount: todos.length,
itemBuilder: (context, index) {
final
todo = todos[index];
return
Dismissible
(
key:
Key
(
'
$
todo
$
index
'
),
onDismissed: (direction) => todos.
removeAt
(index),
background:
Container
(color:
Colors
.red),
child:
ListTile
(title:
Text
(todo)),
);
},
),
),
],
),
floatingActionButton:
FloatingActionButton
(
onPressed: () {
setState
(() {
todos.
add
(controller.text);
controller.
clear
();
});
},
child:
const
Icon
(
Icons
.add),
),
),
);
}
}
