Patent ID: 6982695

Claim:
A method executed on a personal digital assistant for adjusting levels of a viewing parameter for an image screen disposed on the personal digital assistant, wherein the image screen includes pixels having output levels, the method comprising: detecting an activation signal for viewing a parameter control in response to user operation of a mechanical button disposed on the personal digital assistant; in response to receiving the activation signal, displaying one or more graphical user-interface elements, the one or more graphical user-interface elements forming at least a portion of the parameter control on the image screen, the one or more graphical user-interface elements including a bar and a slider; detecting an interaction between a user and the one or more graphical user-interface elements, the interaction corresponding to an adjustment of the viewing parameter from a prior value to a new value; in response to detecting the interaction, adjusting the value of the viewing parameter for the image screen to the new value, wherein adjusting includes adjusting image screen drive voltages to adjusted voltages based on the new value, the pixels being receptive to the image screen drive voltages so that the pixel output levels respond to the adjusted voltages by providing an adjusted image having an adjusted contrast or brightness; wherein detecting an interaction between a user and the one or more graphical user-interface elements includes detecting continuous contact on the image screen of a user-controlled object over the slider along the bar displayed on the image screen, from a first location corresponding to the prior value to a second location corresponding to the new value; wherein said personal digital assistant executes an operating system; and wherein a process, running on said personal digital assistant and executing under control of said operating system, causes the displaying of said graphical user-interface elements.