February 2014
Intermediate to advanced
372 pages
7h
Japanese
Content preview from Backbone.jsアプリケーション開発ガイド
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
3.3
ビュー
39
//
ビューのインスタンスに対応する
DOM
の要素について、ログを記録します
console.log(todoView.el); //
ログには「
<li></li>
」と記録されます
3.3.2
el
とは
ビューにとって中心的な役割を果たしているのが
el
（上記のコードでログに記録されているオブ
ジェクト）です。これは何であり、どのように定義されているのでしょうか。
el
は
DOM
の要素への参照を表し、どのビューにも必ず
1
つ存在します。この
el
によって、
ビューのコンテンツを一度に
DOM
へと追加できるようになります。ブラウザにとって再レイアウ
トや再描画などの処理を最低限に抑えられるため、高速な表示が可能になります。
ビューに
DOM
の要素を関連付ける方法は
2
つあります。ビューのために要素を新規作成して
DOM
に追加するか、ページ上にすでに存在する要素を参照するかのいずれかです。
要素を新たに作成する場合は、ビューに
tagName
、
id
、
className
の各プロパティ（いずれも
省略可）を指定します。指定されたプロパティに基づいて要素が生成され、変数
el
にセットされま
す。プロパティが指定されなかった場合は、
div
要素がデフォルトで生成されます。
先ほどの例では
tagName
として
li
が指定されているため、
li
要素が生成されることになりま
す。以下のコードでは、指定された
ID
とクラスを持つ
ul
要素が生成されます。
var TodosView = Backbone.View.extend({
// ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.