January 2012
Intermediate to advanced
584 pages
11h 56m
Chinese
Content preview from 操作介面設計模式 第二版
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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.
模式
|
269
可取消性（
Cancelability
）
圖
6
-
26
Firefox
這是什麼
提供可以立刻取消一個很花費時間的操作的方式，且沒有副作用。
何時使用
執行一項耗費時間的操作時；它可能會中斷 UI，或是在背景執行，而操作花費的
時間在兩秒以上 — 例如列印檔案、查詢資料庫，或載入一個很大的檔案。又或是
使用者正在進行一項活動，此活動確實或顯然會關閉大多數系統互動，例如當使用
者在情境對話框（modal dialog box）中工作時。
為何使用
使用者會改 變心意。一 旦某個耗費 時間的操作 開始了，使 用者有可能 想要中途停
止，特別是在進度指示器（Progress Indicator）對他們表示操作需要一陣子時。或
可能使用者是不小心開始這個操作的。可取消性的確有助於避免錯誤與狀態回復 —
使用者可以取消他知道最後會失敗的事（像是試圖從已經掛掉的網頁伺服器載入一
個頁面）。
無論如何，如果使用者知道一切操作都是可以取消的，他會更樂意於探索介面並嘗
試新事物。這鼓勵了第一章提到的安全探索（Safe Exploration），因而讓介面更容
易用，學習時更有趣。
原理作法
首先，想看 看能否加快 耗時操作的 進度，讓它 看似即刻完 成。甚至不 需要真的很
快，只要讓使用者感覺它是即刻完成就夠好了。在全球資訊網或網路應用程式上，
這可能是預先下載資料或原始碼 — 在使用者開口要資料之前先傳送到用戶端；或
可能是用漸進的方式傳送資料，一有資料就立刻顯示給使用者看。請記得：人類閱
讀的速度有限。你可以下
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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.