Project Features and Issues

A finding nearby places app built with React, Vite, Flowbite, Tailwind CSS, leafletjs, React Leaflet, Overpass API, zustand, and TypeScript.

Table of Contents

1. Completed Features
2. To-Do Tasks
3. Packages Used
4. Issues Encountered and Solutions
5. Extra Features
6. Reference

Completed Features:

1. Utilized React Query for efficient data fetching and caching, enhancing performance.
2. Expanded categories of places for more comprehensive search options.
3. Implemented storage of the user's current position for enhanced user experience.
4. Added loading UI during data queries for better visual feedback.
5. Enabled single click navigation to any location worldwide directly on the map.
6. Incorporated onScroll events to dynamically adjust card container styles.
7. Implemented functionality to scroll into the corresponding card after clicking on a marker.

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To-Do Tasks:

• Pass Refs to Child Components using forwardRef.
• Implement deep refs forwarding for complex component structures.
• Utilize useRef to store a list of elements efficiently.
• Add custom attributes to div elements for enhanced styling flexibility.
• Create custom hooks for map-related functionalities.
• Explore testing React components using Vitest.

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Packages Used:

• Flowbite
• Tailwind CSS
• Leafletjs
• React Leaflet
• Overpass API
• Zustand
• React Query

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Issues Encountered and Solutions

'require' is not defined

In tailwind.config.js on plugins: [require("flowbite/plugin")],

Solution
ignore eslint

// eslint-disable-next-line no-undef
  plugins: [require("flowbite/plugin")],

Flex col auto wrap child element

Solution
Change the parent layout to lg:inline-block instead of lg:flex-col

Overflow scroll does not work when flex row

Solution
Add missing width: 100vw; w-screen to the flex container

Flex nowrap does not work when flex row

Solution
Add missing height h-full to the flex element

Default scroll looks ugly

Solution
https://www.npmjs.com/package/tailwind-scrollbar

react-leaflet does not show correctly on the page

Solution
https://leafletjs.com/examples/quick-start/
does not work

https://www.npmjs.com/package/react-leaflet?activeTab=dependencies does not work

https://stackoverflow.com/questions/40365440/react-leaflet-map-not-correctly-displayed

https://leafletjs.com/examples/quick-start/ it works

Add link and script and width and height

Add the below codes into index.html

<link
      rel="stylesheet"
      href="https://unpkg.com/leaflet@1.9.4/dist/leaflet.css"
      integrity="sha256-p4NxAoJBhIIN+hmNHrzRCf9tD/miZyoHS5obTRR9BMY="
      crossorigin=""
    />

 <script
  src="https://unpkg.com/leaflet@1.9.4/dist/leaflet.js"
  integrity="sha256-20nQCchB9co0qIjJZRGuk2/Z9VM+kNiyxNV1lvTlZBo="
  crossorigin=""
></script>

Add below codes into src\App.css

.leaflet-container {
  width: 100wh;
  height: 100vh;
}

Default map is on the top of every component

Solution
https://wordpress.org/support/topic/leaflet-map-z-index-and-css/

Add the style z-index: 0 !important; to the leaflet container class .leaflet-container in src\App.css

Change the order of components, make leaflet container component to be the first render component. For example, in src\App.tsx, where <MapLayout /> is the component that includes leaflet container:

import "./App.css";
import MapLayout from "./MapLayout";
import Navigation from "./Navigation";
import ResultContainer from "./ResultContainer";

function App() {
  return (
    <main className="min-h-screen min-w-screen flex">
      <MapLayout />
      <Navigation />
      <ResultContainer />
    </main>
  );
}

export default App;

In src\MapLayout.tsx

import React from "react";
import CurrentLocationButton from "./CurrentLocationButton";
import { MapContainer, Marker, Popup, TileLayer } from "react-leaflet";

export default function MapLayout() {
  return (
    <div className="w-screen h-screen ">
      <MapContainer center={[51.505, -0.09]} zoom={13} scrollWheelZoom={false}>
        <TileLayer
          attribution='&copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors'
          url="https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png"
        />
        <Marker position={[51.505, -0.09]}>
          <Popup>
            A pretty CSS3 popup. <br /> Easily customizable.
          </Popup>
        </Marker>
      </MapContainer>

      <div className="fixed w-10 aspect-square flex items-center place-content-center bottom-64 right-8 lg:bottom-24 lg:right-24">
        <CurrentLocationButton />
      </div>
    </div>
  );
}

Error: Argument of type 'LatLng' is not assignable to parameter of type 'SetStateAction<null>'. Type 'LatLng' provides no match for the signature '(prevState: null): null'.

Solution
Change useState(null); to useState<LatLng | null>(null);

Tasks

Get the user's current location and mark it on the map

https://react-leaflet.js.org/docs/example-events/

https://stackoverflow.com/questions/66500181/how-to-locate-react-leaflet-map-to-users-current-position-and-get-the-borders-f

Add onClick event to the custom go to current location button onClick={() => setGoToCurrentPosition(true)}, to change the state const [goToCurrentPosition, setGoToCurrentPosition] = useState(false);

Monitor the state change in the LocationMarker component. And add the condition in the useEffect, only go to the current location when the state variable goToCurrent is true.

Full codes:

import { LatLng } from "leaflet";
import { useEffect, useState } from "react";
import {
  MapContainer,
  Marker,
  Popup,
  TileLayer,
  useMap,
} from "react-leaflet";
import CurrentLocationIcon from "./CurrentLocationIcon";

type Props = {
  goToCurrentPosition: boolean;
};

function LocationMarker({ goToCurrentPosition }: Props) {
  const [position, setPosition] = useState<LatLng | null>(null);

  const [goToCurrent, setGoToCurrent] = useState(false);

  const map = useMap();

  useEffect(() => {
    setGoToCurrent(goToCurrentPosition);
  }, [goToCurrentPosition]);

  useEffect(() => {
    if (goToCurrent) {
      map.locate().on("locationfound", function (e) {
        setPosition(e.latlng);
        map.flyTo(e.latlng, map.getZoom());
      });
    }
  }, [goToCurrent]);

  return position === null ? null : (
    <Marker position={position}>
      <Popup>You are here</Popup>
    </Marker>
  );
}

export default function MapLayout() {
  const [goToCurrentPosition, setGoToCurrentPosition] = useState(false);

  return (
    <div className="w-screen h-screen ">
      <MapContainer center={[51.505, -0.09]} zoom={13} scrollWheelZoom={false}>
        <TileLayer
          attribution='&copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors'
          url="https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png"
        />
        <Marker position={[51.505, -0.09]}>
          <Popup>
            A pretty CSS3 popup. <br /> Easily customizable.
          </Popup>
        </Marker>

        <LocationMarker goToCurrentPosition={goToCurrentPosition} />
      </MapContainer>

      <button
        className="fixed w-14 aspect-square flex items-center place-content-center bottom-64 right-8 lg:bottom-24 lg:right-24 backdrop-blur shadow-lg p-2 rounded-full"
        onClick={() => setGoToCurrentPosition(true)}
      >
        <CurrentLocationIcon />
      </button>
    </div>
  );
}

List 10 restaurants near the current location

https://opensource.com/article/18/5/how-build-your-first-gis-app

https://www.npmjs.com/package/query-overpass

https://codesandbox.io/s/b7olo?file=/src/service/overpass.ts

Try out overpass api on Postman

Url

https://overpass-api.de/api/interpreter

Method

POST

Header

Content-Type: application/x-www-form-urlencoded;charset=UTF-8

Request body

Query Castles

[out:json];(way[historic=castle](around:10000, 50.0874654,14.4212535);
relation[historic=castle](around:10000, 50.0874654,14.4212535););
out body;>;out skel qt;

Query schools

[out:json];
(node[amenity=school](around:10000, 50.0874654,14.4212535););
out body;>;out skel qt;

Save the current position for sharable use

Use zustand

Show restaurants on the map

Change the icons https://codesandbox.io/s/react-leaflet-icon-material-mx1iu?file=/src/index.js

Get distance information from the current position in km

https://www.geodatasource.com/developers/javascript

Change the corresponding restaurant card style after clicking the marker

Add eventHandlers in Marker

...

<Marker
      position={[position.lat, position.lon]}
      icon={customMarkerIcon}
      eventHandlers={{
        click: (e) => {
          onClickMarker(e);
        },
      }}
    >
      <Popup>{text}</Popup>
    </Marker>

...

In the handler function, set the state variable using the selected position from the event object

...

  const [selectedPosition, setSelectedPosition] = useState<GeoPosition | null>(
    null
  );

  ...

  function onClickCustomMapMarker(event: LeafletMouseEvent): void {
    setSelectedPosition({ lat: event.latlng.lat, lon: event.latlng.lng });
  }

...

Render the selected card component if the position matches the position of the selected marker

...

export default function PlaceContainer({
  currentPosition,
  places,
  selectedPosition,
}: Props) {
  if (places.length > 0) {
    return (
      <section>
        {places.map((place) =>
          selectedPosition !== null &&
          selectedPosition.lat === place.lat &&
          selectedPosition.lon === place.lon ? (
            <PlaceCardSelected

              ...

            />
          ) : (
            <PlaceCard

              ...

            />
          )
        )}
      </section>
    );
  } else {
    return null;
  }
}

Extra Features

Use React Query for efficient data fetching and caching to increase performance

Update and pass queryKey for query

TanStack/query#3200

... zustand

Edit data after calling API

TanStack/query#530

... useMemo

Single chick on the map go to anywhere in the world

https://stackoverflow.com/questions/66288089/how-to-display-a-list-of-points-using-dbclick-in-react-leaflet-v-3-x

onScroll events for changing card container styles

...

Scroll into the card after clicking on the corresponding marker

Pass Refs to Child Components using forwardRef

https://dmitripavlutin.com/react-forwardref/

https://react-typescript-cheatsheet.netlify.app/docs/basic/getting-started/forward_and_create_ref/

Deep refs forwarding

https://dmitripavlutin.com/react-forwardref/#4-deep-refs-forwarding

...

Storing an list of elements using useRef

Possible solution: passing ref as props https://stackoverflow.com/questions/66764686/how-to-pass-a-ref-down-more-than-one-level-in-react

https://eliaslog.pw/how-to-add-multiple-refs-to-one-useref-hook/

Grand child component:

  ...

<PlaceCard
  ref={(element) => {
  if (element) cardRefs.current[index] = element;
  }}
  key={place.id}

  ...

...

Add custom attribute to div

XXX does not exist on type 'DetailedHTMLProps<HTMLAttributes, HTMLDivElement>'

Solution https://stackoverflow.com/questions/46215614/property-does-not-exist-on-type-detailedhtmlprops-htmldivelement-with-react

...

Create custom hooks

https://www.freecodecamp.org/news/how-to-create-react-hooks/

const [showStart, setShowStart] = useState(false);

const [showEnd, setShowEnd] = useState(true);

...

TypeScript: define the return type of the custom hook to be an array with multiple types

https://stackoverflow.com/questions/29382389/defining-array-with-multiple-types-in-typescript

...

Reference

https://github.com/othneildrew/Best-README-Template