Handle change on Autocomplete Component from material ui

Question

I want to use Autocomplete component for input tags. I\'m trying to get the tags and save them on a state so I can later save them on the database. I\'m using funct

Answer 1

Are you sure you used onChange correctly?

onChange signature: function(event: object, value: any) => void

Answer 2

As Yuki already mentioned, make sure you did use the onChange function properly. It receives two parameters. According to the documentation:

Signature: function(event: object, value: any) => void.

event: The event source of the callback

value: null (The value/values within the Autocomplete component).

Here's an example:

import React from 'react';
import Chip from '@material-ui/core/Chip';
import Autocomplete from '@material-ui/lab/Autocomplete';
import TextField from '@material-ui/core/TextField';

export default class Tags extends React.Component {
  constructor(props) {
    super(props);
    this.state = {
      tags: []
    };
    this.onTagsChange = this.onTagsChange.bind(this);
  }

  onTagsChange = (event, values) => {
    this.setState({
      tags: values
    }, () => {
      // This will output an array of objects
      // given by Autocompelte options property.
      console.log(this.state.tags);
    });
  }

  render() {
    return (
      <div style={{ width: 500 }}>
        <Autocomplete
          multiple
          options={top100Films}
          getOptionLabel={option => option.title}
          defaultValue={[top100Films[13]]}
          onChange={this.onTagsChange}
          renderInput={params => (
            <TextField
              {...params}
              variant="standard"
              label="Multiple values"
              placeholder="Favorites"
              margin="normal"
              fullWidth
            />
          )}
        />
      </div>
    );
  }
}

const top100Films = [
  { title: 'The Shawshank Redemption', year: 1994 },
  { title: 'The Godfather', year: 1972 },
  { title: 'The Godfather: Part II', year: 1974 },
  { title: 'The Dark Knight', year: 2008 },
  { title: '12 Angry Men', year: 1957 },
  { title: "Schindler's List", year: 1993 },
  { title: 'Pulp Fiction', year: 1994 },
  { title: 'The Lord of the Rings: The Return of the King', year: 2003 },
  { title: 'The Good, the Bad and the Ugly', year: 1966 },
  { title: 'Fight Club', year: 1999 },
  { title: 'The Lord of the Rings: The Fellowship of the Ring', year: 2001 },
  { title: 'Star Wars: Episode V - The Empire Strikes Back', year: 1980 },
  { title: 'Forrest Gump', year: 1994 },
  { title: 'Inception', year: 2010 },
];

Answer 3

I wanted to update my state when I select an option from the autocomplete. I had a global onChange handler that manages for all inputs

         const {name, value } = event.target;
         setTukio({
          ...tukio,
          [name]: value,
        });

That updates the object dynamically based on the name of the field. But on the Autocomplete the name returns blank. So I changed the handler from onChange to onSelect. Then either create a separate function to handle the change or as in my case added an if statement to check if the name is not passed.

// This one will set state for my onSelect handler of the autocomplete 
     if (!name) {
      setTukio({
        ...tukio,
        tags: value,
      });
     } else {
      setTukio({
        ...tukio,
        [name]: value,
      });
    }

The above approach works if u have a single autocomplete. If you have multiple u can pass a custom function like below

<Autocomplete
    options={tags}
    getOptionLabel={option => option.tagName}
    id="tags"
    name="tags"
    autoComplete
    includeInputInList
    onSelect={(event) => handleTag(event, 'tags')}
          renderInput={(params) => <TextField {...params} hint="koo, ndama nyonya" label="Tags" margin="normal" />}
        />

// The handler 
const handleTag = ({ target }, fieldName) => {
    const { value } = target;
    switch (fieldName) {
      case 'tags':
        console.log('Value ',  value)
        // Do your stuff here
        break;
      default:
    }
  };

Answer 4

I needed to hit my api on every input change to get my tags from backend!

Use Material-ui onInputChange if you want to get your suggested tags on every input change!

this.state = {
  // labels are temp, will change every time on auto complete
  labels: [],
  // these are the ones which will be send with content
  selectedTags: [],
}
}

//to get the value on every input change
onInputChange(event,value){
console.log(value)
//response from api
.then((res) => {
      this.setState({
        labels: res
      })
    })

}

//to select input tags
onSelectTag(e, value) {
this.setState({
  selectedTags: value
})
}


            <Autocomplete
            multiple
            options={top100Films}
            getOptionLabel={option => option.title}
            onChange={this.onSelectTag} // click on the show tags
            onInputChange={this.onInputChange} //** on every input change hitting my api**
            filterSelectedOptions
            renderInput={(params) => (
              <TextField
                {...params}
                variant="standard"
                label="Multiple values"
                placeholder="Favorites"
                margin="normal"
                fullWidth
              />

Answer 5

@Dworo

For anyone that has a problem with displaying a selected item from dropdown in Input field.

I found a workaround. Basically you have to bind a inputValue at onChage for both Autocomplete and TextField , bad Material UI.

const [input, setInput] = useState('');

<Autocomplete
  options={suggestions}
  getOptionLabel={(option) => option}
  inputValue={input}
  onChange={(e,v) => setInput(v)}
  style={{ width: 300 }}
  renderInput={(params) => (
    <TextField {...params} label="Combo box" onChange={({ target }) => setInput(target.value)} variant="outlined" fullWidth />
  )}
/>