DART

flutter clear all text in textfield

TextField(
  controller: _controller,
  decoration: InputDecoration(
    hintText: "Enter a message",
    suffixIcon: IconButton(
      onPressed: () => _controller.clear(),
      icon: Icon(Icons.clear),
    ),
  ),
)

flutter textformfield clear value

final TextEditingController _textController = new TextEditingController();
TextField(
          controller: _textController,
          decoration: InputDecoration(
              hintText: "Username",
              suffixIcon: IconButton(
                onPressed: () {
                  setState(() {
                    _textController.clear();
                  });
                },
              )),
        )

clear textfield dart

//To clear a textField, use a TextEditing Controller
final _controller = TextEditingController();

            Column(
            children: [
              TextField(
                  decoration: InputDecoration(labelText: 'Title'),
                  controller: _controller,
                  onChanged: (value) {
                    titleInput = value;
                  }),
                ElevatedButton(
                  onPressed: () => _controller.clear(),
                  child: Text('Add Transaction!'),
              ),
            ],
          ),

flutter clear textfield

//Initialize a controller inside your State class
TextEditingController _controller = TextEditingController();

//Set the _controller on you TextField
TextField(
  controller: _controller,
  //Rest of your code
)

//Clear the controller after pushing the new page
onPressed: () {
   Navigator.push(context, new MaterialPageRoute(
     builder: (context) => SearchPage(searchText: this.search.text)
   )).then((value) {
      //This makes sure the textfield is cleared after page is pushed.
      _controller.clear();
   });
}

error textfield getting clear flutter

The issue is that you are persisting objects inside a StatelessWidget.

Opening the keyboard tends to rebuild the whole screen (which is fine). But in
my case rebuilding cause your TextEditingController to be GCed because i 
stored them inside a StatelessWidget