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JavaScript

Posted by David Park
David Park
5,095 Points

onTick undefined when application runs.

So if anyone has an issue with the componentdidmount () in the stopwatch.js

convert the function into an arrow function invocation so the this context is preserved.

componentDidMount () {
    // this.interval = setInterval(this.onTick) PREVIOUSLY
        this.interval = setInterval(
        () => this.onTick()
        );
};

In addition if the buttons do not work make sure to bind the this context on the JSX side like so..

        <button onClick={this.onStop.bind(this)}>Stop</button>
        :
        <button onClick={this.onStart.bind(this)}>Start</button>
        }
        <button onClick={this.onReset.bind(this)}>Reset</button>

^ --- you can do this here or in the constructor of the class and bind the funciton this context.

Had this bug running this application on my own React boilerplate, thought it would be helpful to some people if they did the same. :)