GeezerVison is showing javascript.info — Extended clock
back to the lessonExtended clock
importance: 5
We’ve got a Clock class. As of now, it prints the time every second.
class Clock {
constructor({ template }) {
this.template = template;
}
render() {
let date = new Date();
let hours = date.getHours();
if (hours < 10) hours = '0' + hours;
let mins = date.getMinutes();
if (mins < 10) mins = '0' + mins;
let secs = date.getSeconds();
if (secs < 10) secs = '0' + secs;
let output = this.template
.replace('h', hours)
.replace('m', mins)
.replace('s', secs);
console.log(output);
}
stop() {
clearInterval(this.timer);
}
start() {
this.render();
this.timer = setInterval(() => this.render(), 1000);
}
}
Create a new class ExtendedClock that inherits from Clock and adds the parameter precision – the number of ms between “ticks”. Should be 1000 (1 second) by default.
- Your code should be in the file
extended-clock.js
- Don’t modify the original
clock.js. Extend it.
Open a sandbox for the task.
class ExtendedClock extends Clock {
constructor(options) {
super(options);
let { precision = 1000 } = options;
this.precision = precision;
}
start() {
this.render();
this.timer = setInterval(() => this.render(), this.precision);
}
};
Open the solution in a sandbox.