- Install
- Set up an editor
- Test drive
- Write your first Flutter app, part 1
- Learn more
- Flutter for Android developers
- Flutter for iOS developers
- Flutter for React Native developers
- Flutter for web developers
- Flutter for Xamarin.Forms developers
- Introduction to declarative UI
- Cookbook
- Codelabs
- Tutorials
- User interface
- Introduction to widgets
- Layouts in Flutter
- Layout tutorial
- Dealing with box constraints
- Adding interactivity to your Flutter app
- Adding assets and images
- Navigation & routing
- Introduction to animations
- Animations overview
- Animations tutorial
- Hero Animations
- Staggered Animations
- Advanced UI
- Slivers
- Taps, drags, and other gestures
- Widget catalog
- Data & backend
- State management
- State management
- Start thinking declaratively
- Differentiate between ephemeral state and app state
- Simple app state management
- List of state management approaches
- JSON and serialization
- Firebase
- Accessibility & internationalization
- Accessibility
- Internationalizing Flutter apps
- Platform integration
- Writing custom platform-specific code
- Packages & plugins
- Using packages
- Developing packages & plugins
- Background processes
- Tools & techniques
- Android Studio / IntelliJ
- Visual Studio Code
- Upgrading Flutter
- Hot reload
- Code formatting
- Debugging Flutter apps
- Using OEM debuggers
- Flutter's build modes
- Testing Flutter apps
- Performance best practices
- Flutter performance profiling
- Creating flavors for Flutter
- Preparing an Android App for Release
- Preparing an iOS App for Release
- Continuous Delivery using fastlane with Flutter
- Bootstrap into Dart
- Inside Flutter
- Platform specific behaviors and adaptations
- Technical Overview
- Technical videos
- FAQ
- Flutter widget index
- Install
- Windows install
- MacOS install
- Linux install
- Set up an editor
- Write your first Flutter app, part 1
- Learn more
- Cupertino (iOS-style) widgets
- Layout widgets
- Animation and motion widgets
- Retrieve the value of a text field
- Basic widgets
- Material Components widgets
- Animate the properties of a Container
- Fade a Widget in and out
- Add a Drawer to a screen
- Displaying SnackBars
- Exporting fonts from a package
- Updating the UI based on orientation
- Using Themes to share colors and font styles
- Using custom fonts
- Working with Tabs
- Building a form with validation
- Create and style a text field
- Focus on a Text Field
- Handling changes to a text field
- Retrieve the value of a text field
- Adding Material Touch Ripples
- Handling Taps
- Implement Swipe to Dismiss
- Display images from the internet
- Fade in images with a placeholder
- Working with cached images
- Basic List
- Create a horizontal list
- Creating a Grid List
- Creating lists with different types of items
- Place a floating app bar above a list
- Working with long lists
- Report errors to a service
- Animating a Widget across screens
- Navigate to a new screen and back
- Navigate with named routes
- Pass arguments to a named route
- Return data from a screen
- Send data to a new screen
- Fetch data from the internet
- Making authenticated requests
- Parsing JSON in the background
- Working with WebSockets
- Persist data with SQLite
- Reading and Writing Files
- Storing key-value data on disk
- Play and pause a video
- Take a picture using the Camera
- An introduction to integration testing
- Performance profiling
- Scrolling
- An introduction to unit testing
- Mock dependencies using Mockito
- An introduction to widget testing
- Finding widgets
- Tapping, dragging and entering text
- Development
- Introduction to widgets
- Layout tutorial
- Dealing with box constraints
- Adding interactivity to your Flutter app
- Adding assets and images
- Navigation & routing
- Navigate to a new screen and back
- Send data to a new screen
- Return data from a screen
- Navigate with named routes
- Animating a Widget across screens
- AnimatedList
- Sample App Catalog
- Animations overview
- Animations tutorial
- Staggered Animations
- Slivers
- Taps, drags, and other gestures
- Accessibility widgets
- Assets, images, and icon widgets
- Async widgets
- Input widgets
- Interaction model widgets
- Painting and effect widgets
- Scrolling widgets
- Styling widgets
- Text widgets
- State management
- Start thinking declaratively
- Differentiate between ephemeral state and app state
- Simple app state management
- List of state management approaches
- JSON and serialization
- Accessibility
- Internationalizing Flutter apps
- Writing custom platform-specific code
- Using packages
- Fetch data from the internet
- Developing packages & plugins
- Background processes
- Android Studio / IntelliJ
- Set up an editor
- Flutter inspector
- Creating Useful Bug Reports
- Visual Studio Code
- Set up an editor
- Upgrading Flutter
- Hot reload
- Code formatting
Retrieve the value of a text field
In this recipe, we’ll see how to retrieve the text a user has typed into a text field.
Directions
- Create a
TextEditingController
- Supply the
TextEditingController
to aTextField
- Display the current value of the text field
1. Create a TextEditingController
In order to retrieve the text a user has typed into a text field, we need to create a TextEditingController
. We will then supply the TextEditingController
to a TextField
in the next steps.
Once a TextEditingController
is supplied to a TextField
or TextFormField
, we can use it to retrieve the text a user has typed into that text field.
Note: It is also important to dispose
of the TextEditingController
when we are finished using it. This will ensure we discard any resources used by the object.
// Define a Custom Form Widget
class MyCustomForm extends StatefulWidget {
@override
_MyCustomFormState createState() => _MyCustomFormState();
}
// Define a corresponding State class. This class will hold the data related to
// our Form.
class _MyCustomFormState extends State<MyCustomForm> {
// Create a text controller. We will use it to retrieve the current value
// of the TextField!
final myController = TextEditingController();
@override
void dispose() {
// Clean up the controller when the Widget is disposed
myController.dispose();
super.dispose();
}
@override
Widget build(BuildContext context) {
// We will fill this out in the next step!
}
}
2. Supply the TextEditingController
to a TextField
Now that we have a TextEditingController
to work with, we need to wire it up to a specific text field. To do this, we’ll supply the TextEditingController
to a TextField
or TextFormField
Widget as the controller
property.
TextField(
controller: myController,
);
3. Display the current value of the text field
After we’ve supplied the TextEditingController
to our text field, we can begin reading values! We will use the text
method provided by the TextEditingController
to retrieve the String of text the user has typed into the text field.
In this example, we will display an alert dialog with the current value of the text field when the user taps on a floating action button.
FloatingActionButton(
// When the user presses the button, show an alert dialog with the
// text the user has typed into our text field.
onPressed: () {
return showDialog(
context: context,
builder: (context) {
return AlertDialog(
// Retrieve the text the user has typed in using our
// TextEditingController
content: Text(myController.text),
);
},
);
},
tooltip: 'Show me the value!',
child: Icon(Icons.text_fields),
);
Complete example
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Retrieve Text Input',
home: MyCustomForm(),
);
}
}
// Define a Custom Form Widget
class MyCustomForm extends StatefulWidget {
@override
_MyCustomFormState createState() => _MyCustomFormState();
}
// Define a corresponding State class. This class will hold the data related to
// our Form.
class _MyCustomFormState extends State<MyCustomForm> {
// Create a text controller. We will use it to retrieve the current value
// of the TextField!
final myController = TextEditingController();
@override
void dispose() {
// Clean up the controller when the Widget is disposed
myController.dispose();
super.dispose();
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Retrieve Text Input'),
),
body: Padding(
padding: const EdgeInsets.all(16.0),
child: TextField(
controller: myController,
),
),
floatingActionButton: FloatingActionButton(
// When the user presses the button, show an alert dialog with the
// text the user has typed into our text field.
onPressed: () {
return showDialog(
context: context,
builder: (context) {
return AlertDialog(
// Retrieve the text the user has typed in using our
// TextEditingController
content: Text(myController.text),
);
},
);
},
tooltip: 'Show me the value!',
child: Icon(Icons.text_fields),
),
);
}
}
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