I am trying to fetch data from my api and set it in _data state; however, I always get _data state as undefined. First I am pulling a token from asyncstorage before fetching and then I want to save the data from fetching to the state. Can someone please check if I am doing something wrong?
export default class Posts extends React.PureComponent {
constructor(props) {
super(props);
this.fetchData = this._fetchData.bind(this);
this.state = {
isLoading: true,
isLoadingMore: false,
_data: null,
accessToken: "",
};
}
async componentWillMount() {
try {
let accessToken = await AsyncStorage.getItem(ACCESS_TOKEN).then(JSON.parse);
if(!accessToken) {
this.redirect('login');
} else {
this.setState({accessToken: accessToken})
}
} catch(error) {
console.log("Something went wrong");
this.redirect('login');
}
this.fetchData(responseJson => {
const data = responseJson.data;
this.setState({
isLoading: false,
_data: data,
});
});
}
_fetchData(callback) {
fetch(`https://mywebsite.com/posts`,
{
method: 'GET',
headers: {
'Accept': 'application/json',
'Content-Type': 'application/json',
'Authorization': "Bearer " + this.state.accessToken.token,
}
})
.then(response => response.json())
.then(callback)
.catch(error => {
console.error(error);
});
}
Where specifically are you losing the "data" value? Are you sure the responseJson has the "data" value in it?
You may be losing scope to this after the bind() call; try this:
constructor(props) {
var self = this;
super(props);
this.fetchData = this._fetchData.bind(this);
this.state = {
isLoading: true,
isLoadingMore: false,
_data: null,
accessToken: "",
};
// self.data here should be there if this.data is not.
}
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