I'm developing an application that updates Firebase data in realtime to React. What I want to do is that a user updates the state in the app, at the same time it should be updated for another user.
I have built it done but it continually renders renderStatus()
and it's too slow. I want to make it updated once RDB data updated.
class Status extends Component {
constructor(props) {
super(props);
this.state = {
to_status: false,
from_status: false
};
}
// change the state in RDB
handleSatus = () => {
const { post } = this.props;
firebase
.database()
.ref("/busy/" + post.uid)
.set({
status: true,
last_changed: firebase.database.ServerValue.TIMESTAMP
});
this.setState({ to_status: true });
};
renderStatus() {
const { post } = this.props;
const { to_status, from_status } = this.state;
// fetch the data in RDB
let self = this;
firebase
.database()
.ref("/busy/" + post.uid)
.once("value")
.then(function(snapshot) {
self.setState({ from_status: snapshot.val().status });
});
if (this.state.from_status) {
return (
<p>Updated</p>
);
} else {
return (
<p>Not updated yet</p>
);
}
}
render() {
return (
<div>
{this.renderStatus()}
<button onClick={this.handleStatus()}>Click!</button>
</div>
)
}
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