C H A P T E R 4

Pickers

Applications should not attempt to imitate the interface of personal computers by dimming unavailable picker items. Although applications can designate picker items as unselectable, the system does not display them in gray text or otherwise make them visibly different from selectable items. Newton picker items should simply disappear when they are unavailable.

Organization of List Pickers

The items in a list picker should be logically related to each other and to the label, button, or whatever else controls the picker. Arrange the items in a list picker in an order that makes sense and is most convenient to users. In general, start the list with the items most likely to be picked and end the list with the items least likely to be picked. If all items are equally likely to be picked, or if you want to arrange them without prejudice or bias, list them alphabetically.

You can organize a list picker visually, making it easier to locate an item by grouping related items. In a picker that contains several types of items— actions, attributes, values, and states—group the items according to type. In a picker that contains a single type of item, look for another criterion. For instance, the Printer picker in a Print routing slip lists specific printers in one group and commands that access other printers in a second group. The Look For picker in the Find slip has two groups: one for finding text and another for dates.

You put a separator line between groups of items in a list picker. How many separator lines to use is partially an aesthetic decision. Remember that separator lines take up screen space and that the Newton interface relies on aesthetic integrity as a means of good communication. Figure 4-4 contrasts a good balance of grouping with too little grouping and too much grouping.

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List Pickers

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Apple 2 manual Organization of List Pickers

2 specifications

The Apple II is a defining product in the history of personal computing, first introduced in 1977 by Apple Computer, Inc. Designed by Steve Wozniak, the Apple II was one of the first highly successful mass-produced microcomputer products and played a significant role in bringing personal computers into homes and schools.

One of the Apple II's standout features was its color graphics capability. It was one of the first personal computers to provide color output, thanks to its built-in video interface. The initial model supported a resolution of 280x192 pixels with a palette of 6 colors, which allowed for vibrant visuals that set it apart from contemporaries like the monochrome Altair 8800.

The Apple II was notable for its open architecture. This design allowed users to expand the computer's capabilities easily through a series of expansion slots. Users could add floppy disk drives, additional memory, and various peripheral devices, making the system highly adaptable to individual needs. This encouraged a thriving ecosystem of third-party hardware and software, which contributed to its popularity.

Another significant feature was its use of the 6502 microprocessor. This 8-bit CPU was not only affordable but also powerful for its time, allowing the Apple II to run various applications efficiently. Along with a built-in keyboard and an innovative plastic case that housed its components, the design was user-friendly and appealing.

The Apple II also introduced the concept of “bootable software” through the use of floppy disks. The disk operating system (DOS) allowed users to store and run multiple programs without having to reload software manually, providing a level of convenience that had not been widely available before. Key software like VisiCalc, the first spreadsheet program, helped boost sales, showcasing the Apple II's utility in business and education environments.

The computer was also well-known for its early adoption of BASIC programming language. Apple provided an operating system that supported Applesoft BASIC, which enabled users, including students, to write their programs, further fostering a community of developers.

In summary, the Apple II's color graphics, open architecture, powerful 6502 processor, innovative use of floppy disks, and support for BASIC programming made it a revolutionary product in its time. Its legacy laid the groundwork for future personal computers and established Apple as a leader in the burgeoning tech industry. The Apple II remains an iconic symbol of the early personal computing era, reflecting a generation's transition into a digitally connected world.