使用 React Native 的未定义导航器

Question

I'm getting undefine navigator usign React Native

MessageTabs:

 _onPressItem = (item) => { 
  const { navigate } = this.props.navigation;

   //console.log(JSON.stringify(item));
  navigate('SingleConversation', {id: item.id})
};

In the constructor of SingleConversation i get :

var conversation_id = this.navigation.state.params.id;

I'm getting

TypeError: Cannot read property 'state' of undefined

Answer 1

In your constructor of SingleConversation:

constructor(props) {
  super(props);
  // `navigation` is from props, not `this`
  var conversation_id = props.navigation.state.params.id;
}