How to get id from SelectField in material-ui using react?

Question

I have looked and tried the solutions from other questions, but I cannot seem to get it to work. The problem I am facing is that event.target.id and event.target.value do not work here. I have done some research and found out why. Now I just need a way to get the "id" from the selectfield

How do I grab the id, in order to make this function work?

Here I have the select:

          <SelectField
          id="category"
          floatingLabelText="Category"
          value={this.state.value}
          onChange={this.updateTask.bind(this)}
        >
          <MenuItem disabled={true} primaryText="Choose A Category" />
          <MenuItem value="delivery" primaryText="Delivery" />
          <MenuItem value="dog walking" primaryText="Dog Walking" />
          <MenuItem value="house cleaning" primaryText="House Cleaning" />
        </SelectField>

And here is the function:

 updateTask(event, index, value) {
    event.preventDefault();
    let updated = Object.assign({}, this.state.task);
    updated[event.target.id] = event.target.value;
    this.setState({
      task: updated,
      value: value,
    });
  }

Answer 1

Sadly, it's not possible to pass a JSON-Object as value to the above Selects "onChange" method, or - better said - it is possible, but then MaterialUI injects the value stored in the MenuItem (which is now a JSON Object) into the textField of the SelectMenu - so it displays nothing because you can't alter how the value should be displayed. So as of right now, as much as I know, it's only possible to pass one argument via event.target.value. If you need more arguments, like an index as an example, I did accomplish it like this:

In the "onChange" prop of the Select, accept two arguments: the first one is the event to extract the value from, the second one is child-object which was clicked, as is documented here: https://material-ui.com/api/select/

Now you can access the value from event.target.value as well as access any unique property of the child (which you defined first) via child.props.[yourVariable]

in the MenuItem's declaration; set your id as a prop for the menuItem

 {this.state.availableDays.map((day, i) => {
        return (
              <MenuItem id={i} value={day.key}>{day.key}</MenuItem>
               )
   })}

in the Select's "onChange" Method; accept event and child as arguments; access child.props.[yourVariable]

onChange={(event, child) => {this.setState({currentDayString: event.target.value, currentDayIndex: child.props.id}) ,this.displayDataForThisDay() }}

I do realize this question was asked a year ago; but maybe my answer is of help for anyone searching for an answer for this very question