Drawing and Data Visualization

Class Atlas Timeline Chart

Complete the timeline chart for the classroom atlas scenario: includes real content, actionable controls, clear status feedback, and responsive layouts.

Drawing and Data VisualizationTimeline ChartHTMLCanvasJavaScript
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    <header class="mast"><div><span class="eyebrow">paper / timeline chart / INTERMEDIATE</span><h1>Class Atlas Timeline Chart</h1><p class="intro">Complete the timeline chart for the classroom atlas scenario: includes real content, actionable controls, clear status feedback, and responsive layouts.</p></div><span class="scenario">Class Atlas</span></header>
    <div class="composition-split"><aside class="split-note"><b>CASE 02</b><span>Master the semantic structure, responsive layout, keyboard interaction, and state synchronization of timeline charts.</span></aside><section class="demo" aria-label="Class Atlas Timeline Chart Interactive Area"><div class="workflow-guide"><nav class="guide-rail" aria-label="Class Atlas Guidance"><span class="eyebrow">Class Atlas GUIDE</span><ol><li data-workflow-guide-step="0" aria-current="step"><b>1</b><span>Class Atlas current view</span></li><li data-workflow-guide-step="1"><b>2</b><span>Class Atlas Comparison View</span></li><li data-workflow-guide-step="2"><b>3</b><span>Class Atlas Summary View</span></li></ol><div class="guide-actions"><button id="workflowGuideBack" class="action" type="button" disabled>Previous</button><button id="workflowGuideNext" class="action primary" type="button">Complete this step</button></div><div id="workflowGuideProgress" role="progressbar" aria-label="Class atlas completion" aria-valuemin="0" aria-valuemax="100" aria-valuenow="0"><i></i></div></nav><section id="workflowCore" class="workflow-core guide-core" data-guide-step="0" aria-describedby="workflowGuideInstruction"><p id="workflowGuideInstruction">Please complete the actions related to the “Current Classroom Atlas View” in the main example.</p><!-- 11DZ_CORE_START:drawing-data-viz-timeline-chart --><div class="drawing-pattern drawing-pattern-7"><div class="canvas-shell"><canvas id="artboard" width="900" height="440" aria-label="Timeline chart canvas" aria-describedby="canvasDescription"></canvas><div class="canvas-tools panel"><span class="eyebrow">CANVAS MODE 8</span><h2>Timeline Chart</h2><label>Complexity <input id="canvasAmount" type="range" min="4" max="28" value="31"></label><button id="redrawCanvas" class="action primary" type="button">Redraw</button><p id="canvasDescription" class="muted">A timeline chart is drawn on a dark canvas using two high-contrast colors, with the complexity slider determining the number of shapes; the entire scene is generated locally in the browser.</p></div></div><form id="timelineMilestoneForm" class="drawing-controller timeline-controller"><header><span class="eyebrow">MILESTONE EDITOR</span><h3>Class Atlas timeline</h3></header><label>Date<input id="timelineDate" type="date" value="2026-07-13"></label><label>Milestone<input id="timelineLabel" required value="Phase review"></label><button class="action" type="submit" data-core-bridge="drawing-data-viz-timeline-chart">Add to timeline</button><ol id="timelineMilestones"><li data-day="1">Launch</li><li data-day="12">Review</li></ol></form></div><!-- 11DZ_CORE_END --></section><aside class="guide-evidence"><details id="workflowGuideDetails"><summary>View acceptance requirements</summary><ul><li>The classroom atlas current view needs one visible state change</li><li>The class atlas comparison view requires one visible state change</li><li>A visible state change is needed for the classroom atlas summary view</li></ul></details><form id="workflowGuideEvidenceForm"><label>This step evidence<textarea id="workflowGuideEvidence" rows="3" placeholder="Record the observed state"></textarea></label><input class="action" type="submit" value="Save evidence"></form><output id="workflowGuideSummary">0 / 3 Steps Complete</output></aside></div><p id="status" class="status" role="status" aria-live="polite"></p></section></div>
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const timelineForm=document.querySelector('#timelineMilestoneForm');const timelineEvents=[{day:1,label:'Launch'},{day:12,label:'Review'}];function drawTimelineModel(){document.querySelector('#timelineMilestones').replaceChildren(...timelineEvents.sort((left,right)=>left.day-right.day).map(entry=>{const item=document.createElement('li');item.dataset.day=String(entry.day);item.textContent=entry.day+' Day · '+entry.label;item.addEventListener('dblclick',()=>{timelineEvents.splice(timelineEvents.indexOf(entry),1);drawTimelineModel();});return item;}));canvas.dataset.drawingFactor=String(.6+timelineEvents.length*.18);canvas.dataset.drawingShift=String(timelineEvents.reduce((sum,event)=>sum+event.day,0));drawCanvas();}timelineForm.addEventListener('submit',event=>{event.preventDefault();const date=new Date(document.querySelector('#timelineDate').value+'T00:00:00');timelineEvents.push({day:date.getDate(),label:document.querySelector('#timelineLabel').value.trim()});drawTimelineModel();announce('The milestone has been added to the timeline; double-click to remove it');});drawTimelineModel();
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const workflowGuideCore=document.querySelector('#workflowCore');const workflowGuideStages=["Class Atlas current view","Class Atlas Comparison View","Class Atlas Summary View"];const workflowGuideState={step:0,completed:new Set(),evidence:new Map(),consumedVersion:0};function workflowGuideDrive(){const step=workflowGuideState.step;workflowGuideCore.dataset.guideStep=String(step);document.querySelector('#workflowGuideInstruction').textContent='Please complete the main example ‘'+workflowGuideStages[step]+'Related actions.”';document.querySelectorAll('[data-workflow-guide-step]').forEach((item,index)=>{item.classList.toggle('is-complete',workflowGuideState.completed.has(index));if(index===step)item.setAttribute('aria-current','step');else item.removeAttribute('aria-current');});document.querySelector('#workflowGuideBack').disabled=step===0;document.querySelector('#workflowGuideNext').textContent=step===workflowGuideStages.length-1?'Save view':'Complete this step';const percent=Math.round(workflowGuideState.completed.size/workflowGuideStages.length*100);const progress=document.querySelector('#workflowGuideProgress');progress.setAttribute('aria-valuenow',String(percent));progress.querySelector('i').style.width=percent+'%';document.querySelector('#workflowGuideSummary').textContent=workflowGuideState.completed.size+' / '+workflowGuideStages.length+' Step complete · '+workflowBridgeSummary();announce('Class Atlas current step:'+workflowGuideStages[step]);}function workflowGuideAdvance(direction){if(direction>0){const bridge=workflowBridgeActivate();const version=Number(workflowGuideCore.dataset.workflowVersion||0);if(version<=workflowGuideState.consumedVersion){announce('Please complete the visible state change in the main example first');return;}workflowGuideState.consumedVersion=version;workflowGuideState.completed.add(workflowGuideState.step);announce('Main case changes recorded · '+bridge.summary);}workflowGuideState.step=Math.max(0,Math.min(workflowGuideStages.length-1,workflowGuideState.step+direction));workflowGuideDrive();}document.querySelector('#workflowGuideBack').addEventListener('click',()=>workflowGuideAdvance(-1));document.querySelector('#workflowGuideNext').addEventListener('click',()=>workflowGuideAdvance(1));document.querySelector('#workflowGuideEvidenceForm').addEventListener('submit',event=>{event.preventDefault();const version=Number(workflowGuideCore.dataset.workflowVersion||0);if(version<=workflowGuideState.consumedVersion){announce('Evidence not saved: the main example has no new changes yet');return;}const text=document.querySelector('#workflowGuideEvidence').value.trim();workflowGuideState.evidence.set(workflowGuideState.step,text||'Visible status check completed');workflowGuideState.completed.add(workflowGuideState.step);workflowGuideState.consumedVersion=version;workflowGuideDrive();announce('Evidence for this step has been saved · '+workflowBridgeSummary());});document.querySelector('#workflowGuideDetails').addEventListener('toggle',event=>announce(event.currentTarget.open?'Acceptance requirements expanded':'Acceptance requirements collapsed'));workflowGuideDrive();
workflowBridgeReset();
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