UW iSchool Course INFO 474: focused on designing and building visualizations to better understand and communicate about pressing issues.
Observable BasicsFoundations PracticeData Basics: Loading + ManipulatingD3 Activity 1D3 Activity 1 (complete)D3 Activity IID3 Activity II (complete)Graphical Encodings Design ExerciseVisual CognitionVisual Cognition CompleteTreemap ActivityTreemap Activity (complete)D3 Chart ReviewD3 Chart Review (complete)Election Map (complete)Election MapD3 Small MultiplesD3 Small Multiples (complete)Interaction TechniquesInteraction Techniques (complete)Scrolling (complete)
Scroll Starter
// Keep track of the section so that updates only happen when the section changes
mutable currentSection = 0
chart = {
// Overall container
const container = d3.create("div").attr("class", "scroll-container");
// Container for the narrative section
const narrativeContainer = container
.append("div")
.attr("class", "narrative-container");
// Narrative section (holds the text on the left)
const narrative = narrativeContainer.append("div").attr("class", "narrative");
// Add text
narrative
.selectAll(".section")
.data(descriptions)
.join("div")
.attr("class", "section")
.append("h1")
.text(d => d);
// Visualization container
const vis = container.append("div").attr("class", "vis-container");
// Update function (just switches the colors)
const update = section => {
// If the section hasn't changed, don't do anything!
if (section === mutable currentSection) return;
mutable currentSection = section; // If this line of code is here, the cell re-renders
let color = '';
switch (section) {
case 0:
color = "white";
break;
case 1:
color = "pink";
break;
case 2:
color = "green";
break;
case 3:
color = "black";
break;
default:
color = "blue";
break;
}
vis.style("background-color", color);
};
// Add the scrolling listener
narrativeContainer.on("scroll", () => {
// Compute section
const totalHeight = narrativeContainer.node().getBoundingClientRect().top;
const offset = narrative.node().getBoundingClientRect().y;
const section = Math.floor((totalHeight - offset + 10) / sectionHeight);
update(section);
});
return container.node();
}
settings = md`## Settings`
// Descriptions for each section
descriptions = d3.range(0, 5).map(d => "Section " + d)
fullHeight = 400
sectionHeight = 200
narrativeWidth = 200
html`<style>
.scroll-container {
width:${width}px;
height:${fullHeight}px;
}
.narrative-container {
height:${fullHeight}px;
overflow-y:scroll;
float:left;
}
.narrative {
width:${narrativeWidth}px;
}
.vis-container {
height:${fullHeight}px;
width:${width - narrativeWidth - 20}px;
float:right;
}
.section {
height: ${sectionHeight}px;
}
.section:last-of-type {
height:${fullHeight}px;
}
</style>`
d3 = require("d3")
One platform to build and deploy the best data apps
Experiment and prototype by building visualizations in live JavaScript notebooks. Collaborate with your team and decide which concepts to build out.
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