iOS人机交互规范(19)

iOS人机交互规范,为iPhone,iPad开发人员提供设计规范

Metaphors

Metaphors

Whenvirtualobjectsandactionsinanapplicationaremetaphorsforobjectsandactionsintherealworld,usersquicklygrasphowtousetheapp.Theclassicexampleofasoftwaremetaphoristhefolder:Peopleputthingsinfoldersintherealworld,sotheyimmediatelyunderstandtheideaofputtingfilesintofoldersonacomputer.

Themostappropriatemetaphorssuggestausageorexperiencewithoutenforcingthelimitationsofthereal-worldobjectoractiononwhichthey’rebased.Forexample,peoplecanfillsoftwarefolderswithmuchmorecontentthanwouldfitinaphysicalfolder.

iOSprovidesgreatscopeformetaphorsbecauseitsupportsrichgraphicalimagesandgestures.Peoplephysicallyinteractwithrealisticonscreenobjects,inmanycasesoperatingthemasiftheywerereal-worldobjects.MetaphorsiniOSinclude:

●TappingMusicplaybackcontrols

Dragging,flicking,orswipingobjectsinagame

SlidingOn/Offswitches

Flickingthroughpagesofphotos

Spinningpickerwheelstomakechoices ● ● ● ●

Ingeneral,metaphorsworkbestwhenthey’renotstretchedtoofar.Forexample,theusabilityofsoftwarefolderswoulddecreaseiftheyhadtobeorganizedintoavirtualfilingcabinet.

UserControl

People,notapplications,shouldinitiateandcontrolactions.Althoughanapplicationcansuggestacourseofactionorwarnaboutdangerousconsequences,it’susuallyamistakefortheapptotakedecision-makingawayfromtheuser.Thebestappsfindthecorrectbalancebetweengivingpeoplethecapabilitiestheyneedwhilehelpingthemavoiddangerousoutcomes.

Usersfeelmoreincontrolofanappwhenbehaviorsandcontrolsarefamiliarandpredictable.And,whenactionsaresimpleandstraightforward,userscaneasilyunderstandandrememberthem.

Peopleexpecttohaveampleopportunitytocancelanoperationbeforeitbegins,andtheyexpecttogetachancetoconfirmtheirintentiontoperformapotentiallydestructiveaction.Finally,peopleexpecttobeabletogracefullystopanoperationthat’sunderway.