reactjs - ReactNative: undefined is not an object (this.state.listAccounts) - 


class widgets extends component {     constructor(props){         super(props);         this.state = {             accesstoken: "",             listaccounts:[],         }     }     componentwillmount(){         this.setstate({listaccounts: this.loadaccountsdata()})     }     loadaccountsdata(){          //return data server     }     render() {         return (                 <content>                     {this.state.listaccounts.map( (account) => <account accountdata={account} />)}                 </content>         )     } }

above blue print of code. unabele access state in render? error: undefined not object (evaluating 'this.state.listaccounts.map')

you setting state on async request. need wait till response comes set state.

class widgets extends component {     constructor(props){         super(props);         this.state = {             accesstoken: "",             listaccounts:[],         }     }     componentwillmount(){         this.loadaccountsdata();     }     loadaccountsdata(){          somerequest().then( (response) => {              this.setstate({listaccounts: response});              // or whatever data accounts          });     }     render() {         return (                 <content>                     {this.state.listaccounts.map( (account) => <account accountdata={account} />)}                 </content>         )     } }

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