Timer in Spfx (React)

Introduction

In this article, we learn how to implement a timer in SPFx. The 'useTimer' is a react plugin, written using react hooks, that allows us to do timer functions in our component.

Steps

Open a command prompt and create a directory for the SPFx solution.

md spfx-ReactTimer

Navigate to the above-created directory.

cd spfx-ReactTimer

Run the Yeoman SharePoint Generator to create the solution.

yo @microsoft/sharepoint

Solution Name

Hit Enter to have a default name (spfx-ReactTimer in this case), or type in any other name for your solution.

Selected choice - Hit Enter

Target for the component

Here, we can select the target environment where we are planning to deploy the client web part; i.e., SharePoint Online or SharePoint OnPremise (SharePoint 2016 onwards).

Selected choice - SharePoint Online only (latest).

Place of files

We may choose to use the same folder or create a subfolder for our solution.

Selected choice - same folder.

Deployment option

Selecting Y will allow the app to be deployed instantly to all sites and be accessible everywhere.

Selected choice - N (install on each site explicitly).

Permissions to access web APIs

Choose if the components in the solution require permission to access web APIs that are unique and not shared with other components in the tenant.

Selected choice - N (solution contains unique permissions)

Type of client-side component to create

We can choose to create a client-side web part or an extension. Choose the web part option.

Selected choice - WebPart

Web part name

Hit Enter to select the default name or type in any other name.

Selected choice - ReactTimer

Web part description

Hit Enter to select the default description or type in any other value.

Framework to use

Select any JavaScript framework to develop the component. The available choices are - No JavaScript Framework, React, and Knockout.

Selected choice - React

The Yeoman generator will perform a scaffolding process to generate the solution. The scaffolding process will take a significant amount of time.

Once the scaffolding process is completed, lock down the version of project dependencies by running the below command,

npm shrinkwrap

In the command prompt, type the below command to open the solution in the code editor of your choice.

npm i use-timer//for timer function
npm i bootstrap//for bootsrap css its optional

Necessary imports

import { useTimer } from "use-timer";
import "bootstrap/dist/css/bootstrap.min.css";//optional

Full Code

In ReactTimer.tsx

import * as React from 'react';
import { IReactTimerProps } from './IReactTimerProps';
import "bootstrap/dist/css/bootstrap.min.css";
import {BasicTimer,DecrementalTimer,TimerWithEndTime} from './mytimer';
export default class ReactTimer extends React.Component<IReactTimerProps, {}> {
public render(): React.ReactElement<IReactTimerProps> {
return (
<div className="container">
<BasicTimer />
<DecrementalTimer />
<TimerWithEndTime />
</div>
);
}
}

In mytimer.tsx,

import * as React from 'react';
import { useTimer } from "use-timer";
import "bootstrap/dist/css/bootstrap.min.css";
import RunningButton from "./RunningButton";
import "./mystyle.css";
export const BasicTimer = () => {
const { time, start, pause, reset, isRunning } = useTimer();
return (
<div className="card">
<h5 className="card-header">Basic timer</h5>
<div className="card-body">
{isRunning ? (
<RunningButton />
) : (
<button className="btn btn-primary" onClick={start}>
Start
</button>
)}
<button className="btn btn-primary" onClick={pause}>
Pause
</button>
<button className="btn btn-primary" onClick={reset}>
Reset
</button>
</div>
<div className="card-footer">
Elapsed time: <strong>{time}</strong>
</div>
</div>
);
};
export const DecrementalTimer = () => {
const { time, start, pause, reset, isRunning } = useTimer({
initialTime: 100,
timerType: "DECREMENTAL"
});
return (
<div className="card">
<h5 className="card-header">Decremental timer</h5>
<div className="card-body">
{isRunning ? (
<RunningButton />
) : (
<button className="btn btn-primary" onClick={start}>
Start
</button>
)}
<button className="btn btn-primary" onClick={pause}>
Pause
</button>
<button className="btn btn-primary" onClick={reset}>
Reset
</button>
</div>
<div className="card-footer">
Remaining time: <strong>{time}</strong>
</div>
</div>
);
};
export const TimerWithEndTime = () => {
const endTime = 5;
const { time, start, pause, reset, isRunning } = useTimer({
endTime
});
return (
<div className="card">
<h5 className="card-header">Timer with end time</h5>
<div className="card-body">
{isRunning ? (
<RunningButton />
) : (
<button className="btn btn-primary" onClick={start}>
Start
</button>
)}
<button className="btn btn-primary" onClick={pause}>
Pause
</button>
<button className="btn btn-primary" onClick={reset}>
Reset
</button>
</div>
<div className="card-footer">
{time === endTime ? (
<span>Finished!</span>
) : (
<span>
Ellapsed time: <strong>{time}</strong>
</span>
)}
</div>
</div>
);
};

In mystyle.css:

h1, p {
font-family: Lato;
}
button{
margin-right: 5px;
}
.card{
margin-bottom: 30px;
}

In RunningButton.tsx:

import * as React from 'react';
const RunningButton = () => <button className="btn btn-primary" disabled style={{ cursor: 'default'}}>Running...</button>;
export default RunningButton;

Properties

Property	Description
endTime	the value for which timer stops
initialTime	the starting value for the timer
interval	the interval in milliseconds
step	the value to add to each increment/decrement
timerType	the choice between a value that increases ("INCREMENTAL") or decreases ("DECREMENTAL")

Expected Output

Conclusion

In this post, we learned how to implement timers in SPFx. I hope this helps someone, happy coding! :)