CHAPTER 6
Data Input
6-6 Tapping
A scrolling list is not the best way to input one value across a range of values.
Since the full range isn’t visible all at once in a scrolling list, users have a
hard time understanding the scope of their choices. Pickers work well for
listing discontinuous values across a range, such as 1 minute, 5 minutes,
10 minutes, 30 minutes, and Never. Sliders work very well for displaying
a continuous range of values and for letting users choose any value in
the range.
Radio Buttons 6
For a field that can have just one of a few unchanging values, an application
can use a cluster of radio buttons. A user selects an input from a cluster of
radio buttons by tapping one of the radio buttons. This automatically
deselects the previously selected radio button in the cluster. A cluster of
radio buttons always offers the same choices; the radio buttons never change
dynamically depending on context. Figure 6-4 shows a sample cluster of
radio buttons.
Figure 6-4 With radio buttons, a user can select one value for a field
Notice that a cluster of radio buttons offers a user the same choices as a short
picker. On the downside, radio buttons take up more space in a view than
a picker because they are always visible in the view. On the upside, being
always visible makes radio buttons faster and easier to use than a picker.
There’s no need to tap and a wait (however briefly) for anything to pop up.
For a detailed description of radio buttons, see “Radio buttons” on page 3-1.
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