/documentation/videos/02-strokes
#! | 60 lines | 50 code | 10 blank | 0 comment | 0 complexity | 0bd9fe680e392adb07593e724bfd485a MD5 | raw file
1# -*- mode: org -*- 2 3* [[http://www.youtube.com/watch%3Fv%3DMu5FCQmtdJU][Video: Stroke Dialer For Eyes-Free Keypad Input]] 4 5 6The /stroke dialer/ enables one-handed keypad input using the 7touch-screen --- and that without having to even look at the 8screen. Here is how it works --- we start with a brief 9description of the problem that asks the /right/ 10question. The answer becomes self-evident as you follow this 11video. 12 13** The Problem 14 15On-screen keyboards typically show some buttons on the screen 16that you activate by touching the screen. To activate such 17buttons, one needs to look at the screen, because the buttons are 18placed at specific points on the screen, i.e., they are 19/absolutely/ positioned. So what if you want to activate such 20buttons /without/ looking at the screen? 21From the foregoing description, it's clear that the only reason 22one is forced to look at an on-screen keyboard is because the 23buttons are /absolutely/ positioned. So let's relax that 24constraint, let's use /relative/ positioning to place the 25buttons. 26 27We'll start with a keyboard we're all familiar with, the 28telephone keypad. Since we're using relative positioning, 29let's place the center of the keypad /wherever/ you first 30touch the screen. 31So, to dial a _5_, you just touch the screen. 32 33Now, you know where _5_ is --- it's where you first touch 34down. But look, since you know the layout of a phone keypad, you 35can now find all the other digits /relative/ to the _5_. So for 36example, _2_ is directly above _5_ --- so to press _2_, you 37touch down on the screen, and stroke up before lifting your 38finger. 39similarly, you stroke down for an _8_, or diagonally up for a 40_1_. 41 42In real life, we both /hear/ and /feel/ as we press physical 43buttons. This form of synchronized auditory and tactile feedback 44is essential for creating user interfaces that /feel/ 45realistic. The stroke dialer produces a slight vibration as the 46finger moves over the various buttons that is synchronized with 47an auditory /tick/ to achieve this effect. It also produces 48spoken feedback to indicate the button that was pressed. 49 50To conclude this video, let's dial a few numbers. 51 52#+TITLE: Video: Stroke Dialer For Android 53#+AUTHOR: T.V Raman 54#+EMAIL: raman@google.com 55#+DATE: 2009-03-30 Mon 56#+LANGUAGE: en 57#+OPTIONS: H:3 num:t toc:nil \n:nil @:t ::t |:t ^:t -:t f:t *:t 58#TeX:t LaTeX:nil skip:nil d:nil tags:not-in-toc +LINK_UP: 59#http://eyes-free.googlecode.com/svn/trunk/documentation/videos/index.html 60#+LINK_HOME: http://eyes-free.googlecode.com/