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you can set the focus to the text field for the search term. |
this allows the user to start typing as soon as the screen |
is visible, without needing to manually tap the text field. |
in this recipe, learn how to give the focus |
to a text field as soon as it’s visible, |
as well as how to give focus to a text field |
when a button is tapped. |
<topic_end> |
<topic_start> |
focus a text field as soon as it’s visible |
to give focus to a text field as soon as it’s visible, |
use the autofocus property. |
for more information on handling input and creating text fields, |
see the forms section of the cookbook. |
<topic_end> |
<topic_start> |
focus a text field when a button is tapped |
rather than immediately shifting focus to a specific text field, |
you might need to give focus to a text field at a later point in time. |
in the real world, you might also need to give focus to a specific |
text field in response to an API call or a validation error. |
in this example, give focus to a text field after the user |
presses a button using the following steps: |
<topic_end> |
<topic_start> |
1. create a FocusNode |
first, create a FocusNode. |
use the FocusNode to identify a specific TextField in flutter’s |
“focus tree.” this allows you to give focus to the TextField |
in the next steps. |
since focus nodes are long-lived objects, manage the lifecycle |
using a state object. use the following instructions to create |
a FocusNode instance inside the initState() method of a |
state class, and clean it up in the dispose() method: |
<code_start> |
// define a custom form widget. |
class MyCustomForm extends StatefulWidget { |
const MyCustomForm({super.key}); |
@override |
State<MyCustomForm> createState() => _MyCustomFormState(); |
} |
// define a corresponding state class. |
// this class holds data related to the form. |
class _MyCustomFormState extends State<MyCustomForm> { |
// define the focus node. to manage the lifecycle, create the FocusNode in |
// the initState method, and clean it up in the dispose method. |
late FocusNode myFocusNode; |
@override |
void initState() { |
super.initState(); |
myFocusNode = FocusNode(); |
} |
@override |
void dispose() { |
// clean up the focus node when the form is disposed. |
myFocusNode.dispose(); |
super.dispose(); |
} |
@override |
widget build(BuildContext context) { |
// fill this out in the next step. |
} |
} |
<code_end> |
<topic_end> |
<topic_start> |
2. pass the FocusNode to a TextField |
now that you have a FocusNode, |
pass it to a specific TextField in the build() method. |
<code_start> |
@override |
widget build(BuildContext context) { |
return TextField( |
focusNode: myFocusNode, |
); |
} |
<code_end> |
<topic_end> |
<topic_start> |
3. give focus to the TextField when a button is tapped |
finally, focus the text field when the user taps a floating |
action button. use the requestFocus() method to perform |
this task. |
<code_start> |
FloatingActionButton( |
// when the button is pressed, |
// give focus to the text field using myFocusNode. |
onPressed: () => myFocusNode.requestFocus(), |
), |
<code_end> |
<topic_end> |
<topic_start> |
interactive example |
<code_start> |
import 'package:flutter/material.dart'; |
void main() => runApp(const MyApp()); |
class MyApp extends StatelessWidget { |
const MyApp({super.key}); |
@override |
widget build(BuildContext context) { |
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