SelectField needs more methods

[jenil]

Can we have getValue and setValue methods for SelectFields?

I understand SelectField and DropDownMenu are undergoing a lot of change recently but these methods will be a good-to-have.

[alitaheri]

@jgog these methods are imperative and make handling the flow of data really hard, that's why we prefer not to support them (directly) but the fact is, it's very easy to write a wrapper component to expose such methods. and of course, you'll need only one wrapper:

class ImperativeWrapper extends React.Component {

  constructor(props) {
    super(props);
    this.state = {value: props.defaultValue};
  }

  setValue = value => this.setState({value});
  getValue = () => this.state.value;
  clearValue = () => this.setState({value: this.props.defaultValue});

  handle = value => this.setState({value});

  render() {
    const {Component, ...other} = this.props;
    return <Component {...other} value={this.state.value} onChange={this.handle}/>;
  }
}

And you would use it like this:

//...

getAllValues() {
   // The imperative method...
   const selectValue = this.refs['my-select-field'].getValue();
}

render() {
  return (
    <ImperativeWrapper 
      ref="my-select-field"
      defaultValue={/*...*/}
      items={/*...*/}
      // And other SelectField props you want to pass down
      Component={SelectField}/>
}
//...

Although this might need a bit of tweaking to make SelectField work with it (and I apologize, I don't have the time to test it my self), but you get the point. We can provide such wrappers as helper components, but that will have to be decided on.

@oliviertassinari Thoughts?

[jenil]

@subjectix Thanks for the explanation, but I thought a SelectField was suppose to work as the html <select> and the value prop should be a part of the FormData when wrapped in a form.
I didn't understand how the handling of data flow becomes hard in case of a SelectField. And I think the onChange way of interaction with the component is more suitable for the DropDownMenu but for SelectField it should be treated as a form element.

[oliviertassinari]

Will be fixed by the <StateWrapper /> of #2957.