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JavaScript React by Example Building the Application Removing Names From the List

Humberto Ventura
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Humberto Ventura
Front End Web Development Techdegree Graduate 14,734 Points
Posted by Humberto Ventura
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Humberto Ventura
Front End Web Development Techdegree Graduate 14,734 Points

Why do I get TypeError: x is not a function? I

I did everything as Gui says in the video, tried the steps to add a remove name function and I got this error everytime the handler calls the function.Why?

Antti Lylander
Antti Lylander
9,686 Points
Antti Lylander
Antti Lylander
9,686 Points

Please, share your code. It's impossible to say without it. :)

Humberto Ventura
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.a{fill-rule:evenodd;}techdegree seal-36
Humberto Ventura
Front End Web Development Techdegree Graduate 14,734 Points
Humberto Ventura
.a{fill-rule:evenodd;}techdegree seal-36
Humberto Ventura
Front End Web Development Techdegree Graduate 14,734 Points

(App,js) removeGuest = index => this.setState({ guests:[ ...this.state.guests.slice(0,index), ...this.state.guests.slice(index +1) ] });

// component in guest list removeGuest = {this.state.removeGuest }

(GuestList.js)

// handler handleRemove ={() => props.removeGuest(index)} --THIS IS THE LINE OF CODE THE COMPILER SAYS THE ERROR IS, IT SAYS removeGuest() IS NOT A FUNCTION

// In proptypes removeGuest: PropTypes.func.IsRequired,

(Guest.js)

<button onClick = {props.handleRemove}>remove</button>

//proptypes handleRemove:PropTypes.func.isRequired,

Thanks!

1 Answer

jay aljoe
jay aljoe
4,113 Points
jay aljoe
jay aljoe
4,113 Points

you have made a mistake when passing "removeGuest" to "GuestList" component

// This is wrong
 removeGuest = {this.state.removeGuest }
// This is correct
 removeGuest = {this.removeGuest }

you could also implement "removeGuestAt" like this which is a little better

  // remove user
  removeGuestAt = index => this.setState({
    guests:[
      ...this.state.guests.filter( (element, idx) => index !== idx)  
    ]
  });