constructor(props) {
super(props);
this.state = this.getTime();
}
setTimer() {
clearTimeout(this.timeout);
this.timeout = setTimeout(this.updateClock.bind(this), 1000);
}
updateClock() {
this.setState(this.getTime, this.setTimer);
}it is a little hard to understand when someone sets the update state, in this way. Can anyone click on it?
take a look at setState's function signature.
The first argument tosetState can be a partialState or a function, or a function that accepts previousState if it is a function.
The second parameter ofsetState is callback
this.getTime you don't write a definition, but it must be a function that accepts state. Maybe so?
const getTime = state => Object.assign(...state, ...{a: 1}) // so your code means * pass the current state to getTime to process the returned object as a new state,
and then call setTime *
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