how can I use state for multiple value?

Question

I am trying to use two states in my Add Customer JS one is used to hide the form and the second is used for JSON.

I want to use form-State to hide a form on cancel button click and the initial-State for JSON.

I want to do something like this Is it possible to have two states in one react component

import React from 'react';
import { Button, Form, Modal } from 'semantic-ui-react';

export default class AddCustomer extends React.Component {

constructor(props) {
    super(props);
    this.state = {
        showCreateForm:false,
        formData:{
            name: '',
            address: ''
        }
    }
    this.handleChangeName = this.handleChangeName.bind(this);
    this.handleChangeAddress = this.handleChangeAddress.bind(this);
    this.handleSubmit = this.handleSubmit.bind(this);
}

handleChangeName(event) {
    const value = event.target.value;

    console.log(value);

    this.setState({formData:{name:value}});

    //name: ""
    //address: ""
    console.log(this.state.formData);
}

handleChangeAddress(event) {
    const value = event.target.value;
    console.log(value);
    this.setState({formData:{address:value}});

    //name: "ram" but now there is no address in formData
    console.log(this.state.formData);
}

handleSubmit(event) {
    event.preventDefault();

    ////address: "aaaaa" now there no name in formData
    console.log(this.state.formData);

    this.setState({formData:{
        name:this.state.name, address:this.state.address
    }});
    this.props.onAddFormSubmit(this.state.formData);
}

//On cancel button click close Create user form
closeCreateForm = () => {
    this.setState({ showCreateForm: false })
}

//Open Create new Customer form
openCreateCustomer = () => {
    this.setState({ showCreateForm: true })
}

render() {

    return (
        <div>
            <Modal closeOnTriggerMouseLeave={false} trigger={
                <Button color='blue' onClick={this.openCreateCustomer}>
                    New Customer
        </Button>
            } open={this.state.showCreateForm}>
                <Modal.Header>
                    Create customer
    </Modal.Header>
                <Modal.Content>
                    <Form onSubmit={this.handleSubmit}>

                        <Form.Field>
                            <label>Name</label>
                            <input type="text" placeholder ='Name' name = "name"
                                value = {this.state.name} 
                                onChange = {this.handleChangeName}/>
                        </Form.Field>

                        <Form.Field>
                            <label>Address</label>
                            <input type="text" placeholder ='Address' name = "address"
                                value = {this.state.address}
                                onChange = {this.handleChangeAddress}/>
                        </Form.Field>
                        <br/>
                        <Button type='submit' floated='right' color='green'>Create</Button>
                        <Button floated='right' onClick={this.closeCreateForm} color='black'>Cancel</Button>
                        <br/>
                    </Form>

                </Modal.Content>
            </Modal>

        </div>
    )
}

}

Answer 1

As it was already mentioned, yes, you could do it in the constructor. However you could go even further and declare it as a class member. Like following:

export default class Customer extends React.Component {
  state = {
    showCreateForm: false,
    form: {
      name: "",
      address: "",
    }
  }

  constructor(props) {
    super(props);
    this.handleChange = this.handleChange.bind(this);
    this.handleSubmit = this.handleSubmit.bind(this);
  }

  handleSubmit(event) {
    event.preventDefault();
    this.props.onAddFormSubmit(this.state.form);
    this.setState({
      ...this.state,
      form: {
        name: "",
        address: "",
      }
    });
  }



  // ...

  render() {
    return (
      <div>
        <Modal
          closeOnTriggerMouseLeave={false}
          trigger={
            <Button color="blue" onClick={this.openCreateCustomer}>
              New Customer
            </Button>
          }
          open={this.state.showCreateForm}
        >
          <Modal.Header>Create customer</Modal.Header>
          <Modal.Content>
            <Form onSubmit={this.handleSubmit}>
              <Form.Field>
                <label>Name</label>
                <input
                  type="text"
                  placeholder="Name"
                  name="name"
                  value={this.state.form.name}
                  onChange={this.handleChange}
                />
              </Form.Field>
              <Form.Field>
                <label>Address</label>
                <input
                  type="text"
                  placeholder="Address"
                  name="address"
                  value={this.state.form.address}
                  onChange={this.handleChange}
                />
              </Form.Field>
              <br />
              <Button type="submit" floated="right" color="green">
                Create
              </Button>
              <Button
                floated="right"
                onClick={this.closeCreateForm}
                color="black"
              >
                Cancel
              </Button>
              <br />
            </Form>
          </Modal.Content>
        </Modal>
      </div>
    );
  }
}

Answer 2

You can directly give initial state on the constructor. e.g

this.state ={showCreateForm: false, formModel:{name:'abc', address:'xyz'}}

Yes, you can have multiple state variables technically.