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Cannot be used new contextType API in constructor?

See original GitHub issue

Do you want to request a feature or report a bug? feature

What is the current behavior? Using Component.contextType, this.context keeps null in class component’s constructor.

What is the expected behavior?

this.context can be obtained in constructor
if implementing of the feature is inappropriate, write in documentations that this.context cannot be used in constructor.

Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React? React 16.6 (older React doesn’t have Component.contextType) in Chrome 70 (Windows 7)

Issue Analytics

State:
Created 5 years ago
Comments:9 (3 by maintainers)

Top GitHub Comments

74reactions

awearycommented, Oct 24, 2018

@maisumakun how are you calling super in the constructor? If you pass context to super it’s accessible as expected.

https://codesandbox.io/s/l47jw5ryyz

class App extends React.Component {
  static contextType = Context
  constructor(props, context) {
    super(props, context)
    // this.context now works
  }

This seems consistent with this.props. If you don’t pass props to super you cannot access this.props in the constructor. Should this.context work differently?

9reactions

OdenigboGodfreycommented, Mar 4, 2021

super(props, context) is deprecated now also :sigh