How do you change the value inside of a textfield

问题:

I have a TextEditingController where if a user clicks a button it fills in with information. I can't seem to figure out how to change the text inside of a Textfield or TextFormField. Is there a solution?

回答1:

Simply change the text property

    TextField(
      controller: txt,
    ),
    RaisedButton(onPressed: () {
        txt.text = "My Stringt";
    }),

while txt is just a TextEditingController

  var txt = TextEditingController();

回答2:

_mytexteditingcontroller.value = new TextEditingController.fromValue(new TextEditingValue(text: "My String")).value;

This seems to work if anyone has a better way please feel free to let me know.

回答3:

You can use the text editing controller to manipulate the value inside a textfield.

var textController = new TextEditingController();

Now, create a new textfield and set textController as the controller for the textfield as shown below.

 new TextField(controller: textController)

Now, create a RaisedButton anywhere in your code and set the desired text in the onPressed method of the RaisedButton.

new RaisedButton(
       onPressed: () {
          setState(() {
             textController.text = "New text";
          });
       }
    ),

回答4:

The problem with just setting

_controller.text = "New value";

is that the cursor will be repositioned to the beginning (in material's TextField). Using

_controller.text = "Hello";
_controller.selection = TextSelection.fromPosition(
    TextPosition(offset: _controller.text.length),
);
setState(() {});

is not efficient since it rebuilds the widget more than it's necessary (when setting the text property and when calling setState).

--

I believe the best way is to combine everything into one simple command:

final _newValue = "New value";
_controller.value = TextEditingValue(
      text: _newValue,
      selection: TextSelection.fromPosition(
        TextPosition(offset: _newValue.length),
      ),
    );

It works properly for both Material and Cupertino Textfields.

回答5:

Using this solution, you will also be able to put the cursor at the end of newly text.

final TextEditingController _controller = TextEditingController();

@override
Widget build(BuildContext context) {
  return Scaffold(
    body: Center(child: TextField(controller: _controller)),
    floatingActionButton: FloatingActionButton(
      onPressed: () {
        _controller.text = "Hello";

        // this changes cursor position
        _controller.selection = TextSelection.fromPosition(TextPosition(offset: _controller.text.length));
        setState(() {});
      },
    ),
  );
}

回答6:

First Thing

  TextEditingController MyController= new TextEditingController();

Then add it to init State or in any SetState

    MyController.value = TextEditingValue(text: "ANY TEXT");

回答7:

step 1) Declare TextEditingController.

step 2) supply controller to the TextField.

step 3) user controller's text property to change the value of the textField.

follow this official solution to the problem