mapStateToProps doesn't change state

问题

I'm new to redux and want to learn it, I want to make redirect to dashboard content after succesful login, here is my code:

class Dashboard extends Component {
  state = {
    logged: false
  };
render() {
    const { classes } = this.props;
    console.log(this.state.logged)

    return (
<div>
{this.state.logged ?
<div>
<p>Hello</p>
</div>
: Login()
</div>
)}
}

const mapStateToProps = (state, props) => {
  return {
      logged: state.logged
  }
}

export default connect(mapStateToProps)(Dashboard)

reducer:

const initialState = {
    login: [],
    logged: false
}

function rootReducer(state = initialState, action) {
    switch(action.type) {
        case VALIDATE_LOGIN:
            return  {
                    // logged: action.text.name == "a" && action.text.password == "b" ? true : false,
                    ...state,
                    logged: true
                }
        default:
            return state
    }

}

export default rootReducer

why it doesn't want to change state of dashboard and render proper content? Thanks

EDIT here I add code where i dispatch my reducer: Login:

class Login extends Component {
  state = {
    name: "",
    password: ""
  };


  handleLogin = () => {
    this.props.LogIn(this.state)
  }

  render() {
    return (
      <div>
        <Typography variant="h3">
          Login Form
        </Typography>
        <form>
          <TextField label="name" onChange={el => this.setState({name: el.target.value})} />
          <TextField label="password" type="password" onChange={el => this.setState({password: el.target.value})} />
          <Button onClick={this.handleLogin}>Login</Button>
        </form>
      </div>
    );
  }
}

const dispatchToProps = dispatch => {
  return {
    LogIn: login => dispatch(LogIn(login))
  }
}

export default connect(null, dispatchToProps)(Login);

when I try to console log logged in mapStateToProps then i can see that logged has changed to true, but unfortunatelly no visible effect on the dashboard. My idea is that maybe it doesn't rerender after changing state but I dont know...

回答1:

Change

{this.state.logged ?
<div>
<p>Hello</p>
</div>
: Login()
</div>
)}

with

{this.props.logged ?
<div>
<p>Hello</p>
</div>
: Login()
</div>
)}

回答2:

mapStateToProps maps "state" (redux state) to "props" (component props). Not "state" to "state"

class Dashboard extends Component {
  render() {
    const { classes, logged } = this.props

    return (
      <div>
        {logged ? (
          <div>
            <p>Hello</p>
          </div>
        ) : (
          Login()
        )}
      </div>
    )
  }
}

Also do not specify second argument in mapStateToProps if you don't actually use it. This prevents optimization done by react-redux.

const mapStateToProps = (state) => {
  return {
      logged: state.logged
  }
}

来源：https://stackoverflow.com/questions/56899702/mapstatetoprops-doesnt-change-state

标签

reactjs

redux