---
id: w3css-tabulators
title: "W3CSS Tabulators"
category: "Programming_Language"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["navigation tabs", "tabbed content", "openCity", "W3.CSS 탭"]
duplicate_of: ""
source_trust_level: "B"
confidence_score: 0.87
created_at: 2026-07-04
updated_at: 2026-07-04
review_reason: ""
merge_history: []
tags: ["w3css", "css-framework", "w3schools", "tabs"]
raw_sources: ["https://www.w3schools.com/w3css/w3css_tabulators.asp"]
applied_in: []
github_commit: ""
---

# [[W3CSS Tabulators]]

## 🎯 한 줄 통찰 (One-line insight)
Tabbed navigation has NO dedicated `w3-tab*` class family at all — it's fully assembled from primitives already covered in earlier chapters (`w3-bar`/`w3-button` for the clickable tab strip, plain `display:none`/`display:block` toggling for content panels), demonstrating that W3.CSS deliberately favors composing existing utilities over adding single-purpose components for every UI pattern. [S1]

## 🧠 핵심 개념 (Core concepts)
- **Same-class content panels** — all tab panels share one class (e.g. `city`), and JS loops over `getElementsByClassName` to hide all before showing the target one. [S1]
- **`openCity()` pattern** — the canonical two-step JS: hide everything with the shared class, then set the target element's `display` to `block`. [S1]
- **Active-tab highlighting** — mirrors the accordion pattern: loop over elements with a shared `tablink` class, strip a color class from all, then add it to `evt.currentTarget`. [S1]
- **Vertical tabs** — swapping the tab strip's container to `w3-sidebar w3-bar-block` turns horizontal tabs into vertical ones with zero change to the panel-toggling JS. [S1]
- **Closable tab content** — reuses the `w3-display-container`/`w3-display-topright` overlay-positioning pattern with an inline `onclick="this.parentElement.style.display='none'"`. [S1]

## 📖 세부 내용 (Details)
- Core toggle function: `function openCity(cityName) { var i; var x = document.getElementsByClassName("city"); for (i = 0; i < x.length; i++) { x[i].style.display = "none"; } document.getElementById(cityName).style.display = "block"; }`. [S1]
- Active-tab color highlighting variant: `tablinks[i].className = tablinks[i].className.replace(" w3-red", ""); ... evt.currentTarget.className += " w3-red";`. [S1]
- Vertical tab strip: `<nav class="w3-sidebar w3-bar-block w3-light-grey" style="width:130px"><button class="w3-bar-item w3-button" onclick="openCity(event, 'London')">London</button>...</nav>`. [S1]

## ⚖️ 모순 및 업데이트 (Contradictions & updates)
- 현재까지 발견된 모순 사항 없음 (No contradictions found in available sources).

## 🛠️ 적용 사례 (Applied in summary)
현재 발견된 실제 적용 사례가 없습니다 — 이미지 갤러리에 탭 전환 로직을 그대로 재사용하는 "Tabbed Image Gallery" 패턴이 openCity() 함수의 범용성을 보여주는 실전 사례다. [S1]

## 💻 코드 패턴 (Code patterns)
The canonical tab-toggling JavaScript pattern reused throughout the chapter:
```javascript
function openCity(cityName) {
  var i;
  var x = document.getElementsByClassName("city");
  for (i = 0; i < x.length; i++) {
    x[i].style.display = "none";
  }
  document.getElementById(cityName).style.display = "block";
}
```

## ✅ 검증 상태 및 신뢰도
- **상태:** draft
- **검증 단계:** conceptual
- **출처 신뢰도:** B (W3Schools — widely used educational reference, not a primary standards body)
- **신뢰 점수:** 0.87
- **중복 검사 결과:** 신규 생성 (New discovery)

## 🔗 지식 그래프 (Knowledge Graph)
- **상위/루트:** [[W3.CSS Tutorial]]
- **관련 개념:** [[W3CSS Sidebar]], [[W3CSS Accordions]], [[W3CSS Pagination]]
- **참조 맥락:** UI Components 섹션 첫 항목 — 페이지네이션(Pagination) 챕터로 이어짐.

## 📚 출처 (Sources)
- [S1] W3Schools — W3.CSS Navigation Tabs — https://www.w3schools.com/w3css/w3css_tabulators.asp

## 📝 변경 이력 (Change history)
- 2026-07-04: Initial draft synthesized from the W3Schools "W3.CSS Navigation Tabs" page (Astra wiki-curation, P-Reinforce v3.1 format).