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Here’s GeoJSONny and buttons

Adding functionality to our Leaflet.js map!

Goals

  • Create a GeoJSON online and it to the map with JavaScript
  • Understand how JavaScript works with HTML and CSS
  • Understand how JavaScript variables, functions, methods work together

Starting Template Code for lab #3

Use the following template code or your lab assignment #2:

2 Labs, 2 day!

Because we will be doing 2 labs today, we will making two copies of this code. You can save yourself time by doing the following:

  • Make a copy of index.html as part1.html

  • Make a copy of js/init.js to js/part1.js

index.html
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<!DOCTYPE html>
<html>
    <head>
        <title>Hello World</title>
        <!-- hint: remember to change your page title! -->
        <meta charset="utf-8" />
        <link rel="shortcut icon" href="#">
        <link rel="stylesheet" href="styles/style.css">

        <!-- Leaflet's css-->
        <link rel="stylesheet" href="https://unpkg.com/leaflet@1.7.1/dist/leaflet.css" />

        <!-- Leaflet's JavaScript-->
        <script src="https://unpkg.com/leaflet@1.7.1/dist/leaflet.js"></script>
    </head>

    <body>
        <header>
            <!-- space for a menu -->
        </header>

        <div class="main">
            <div id="contents">
                <!-- page contents can go here -->
            </div>
            <div id="the_map"></div>
        </div>
        <div id="footer">
            Copyright(2022)
        </div>
        <script src="js/init.js"></script>
    </body>
</html>
styles/style.css
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body{
    display: grid;
    /* grid-template-columns: 1fr;  */
    grid-auto-rows: auto 1fr;
    grid-template-areas: "header" "main_content" "footer";
    background-color: aqua;
    /* height: 100vh; */
}

header{
    grid-area: header;
}

#footer{
    grid-area: footer;
}

.main{
    grid-area: main_content;
    grid-template-areas: "content" "main_map";
    display: grid;
}

#contents{
    grid-area: content;
}

#the_map{
    height:80vh;
    grid-area: main_map;
}
js/init.js
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// declare the map
const map = L.map('the_map').setView([34.0709,-118.444], 5);

L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
    attribution: '&copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors'
}).addTo(map);

addMarker(37,-122,'home','home land!')
addMarker(32,-118,'work','where i work land!')
addMarker(39,-119,'location 1','random location')
addMarker(36,-120,'location 2','another random location')

// create a function to add markers
function addMarker(lat,lng,title,message){
    console.log(message)
    L.marker([lat,lng]).addTo(map).bindPopup(`<h2>${title}</h2> <h3>${message}</h3>`)
    return message
}