iOS人机交互规范(11)

iOS人机交互规范,为iPhone,iPad开发人员提供设计规范

PlatformCharacteristics

DeviceOrientationCanChange

Note Pixelistheappropriateunitofmeasurementtousewhendiscussingthesizeofadevice

screenorthesizeofaniconyoucreateinanimage-editingapplication.Pointistheappropriateunit

ofmeasurementtousewhendiscussingthesizeofanareathatisdrawnonscreen.

Onastandard-resolutiondevicescreen,onepointequalsonepixel,butotherresolutionsmight

dictateadifferentrelationship.OnaRetinadisplay,forexample,onepointequalstwopixels.

See“PointsVersusPixels”inViewProgrammingGuideforiOSforacompletediscussionofthisconcept.

DeviceOrientationCanChange

PeoplecanrotateiOS-baseddevicesatanytimeandforavarietyofreasons.Forexample,sometimesthetaskpeopleareperformingfeelsmorenaturalinportrait,andsometimespeoplefeelthattheycanseemoreinlandscape.Whatevertheirreasonforrotatingthedevice,peopleexpecttheapptomaintainitsfocusontheprimaryfunctionality.

PeopleoftenlaunchappsfromtheHomescreen,sotheytendtoexpectallappstostartinthesameorientation.BecauseofthedifferentwaysiPhoneandiPaddisplaytheHomescreen,thisexpectationaffectsappsindifferentways:

●OniPhoneandiPodtouch,theHomescreenisdisplayedinoneorientationonly,whichisportrait,with

theHomebuttonatthebottom.ThisleadsuserstoexpectiPhoneappstolaunchinthisorientationbydefault.

OniPad,theHomescreenisdisplayedinallorientations,souserstendtoexpectiPadappstolaunchinthedeviceorientationthey’recurrentlyusing. ●

AppsRespondtoGestures,NotClicks

Peoplemakespecificfingermovements,calledgestures,tooperatetheuniqueMulti-TouchinterfaceofiOS-baseddevices.Forexample,peopletapabuttontoactivateit,flickordragtoscrollalonglist,orpinchopentozoominonanimage.

TheMulti-Touchinterfacegivespeopleasenseofimmediateconnectionwiththeirdevicesandenhancestheirsenseofdirectmanipulationofonscreenobjects.

Peoplearecomfortablewiththestandardgesturesbecausethebuilt-inapplicationsusethemconsistently.Theirexperienceusingthebuilt-inappsgivespeopleasetofgesturesthattheyexpecttobeabletousesuccessfullyinmostotherapps.