Chapter 5 (Advanced Widgets) of WebOS Book Now Available | webOS Nation
 
 

Chapter 5 (Advanced Widgets) of WebOS Book Now Available

by Jennifer Chappell Thu, 30 Apr 2009 9:01 am EDT

Chapter 5 of the Palm webOS book by Mitch Allen is now available from Safari Books Online.

Chapter 5 completes the review of the Mojo widgets with a look at Indicators, Pickers and Viewers, the Filter List and the Scroller. Not all applications will use the Mojo widgets because they're each designed for specific use cases. The widgets are just as simple to work with as the widgets that were previously discussed in Chapter 3 and Chapter 4.

First up, Chapter 5 talks about the Indicators. We're all familiar with Indicators. They show that activity is taking place even if it's not visible, and in some cases, to show some measure of the progress that the activity is making. I'm sure those of you who use a Windows computer are used to seeing that hourglass indicator, showing that something is happening. By reading in Chapter 5, we can get a feel for what the Indicator widgets will look like on the WebOS devices like the Pre.

Read on for a couple screen shots

Mojo has four indicator widgets, but they belong to two types:

  1. Activity indicator, or Spinner, which spins without showing progress
  2. Progress indicator, which shows both activity and progress

Below is an example that Chapter 5 shows of a Spinner on a Google News feed item.

 

Even though the Spinner is the only activity indicator, there are 3 Progress indicator widgets:

  1. Progress Pill, a wide pill which is styled to match the View menu and the .palm-header scene style
  2. Progress Bar, a narrow horizontal bar with a blue progress indicator
  3. Progress Slider, which is intended for streaming media playback applications

Here is an example of a Progress Pill.

Looks familiar, huh? I'm used to seeing similar progress pills at the bottom of my screen on Web pages all the time.

Chapter 5 goes on to explain how the other widgets such as the Scroller, Picker, and Viewers work. You'll see examples of code views and read about how to put in and use all the widgets.

Even though I don't know a thing about developing apps, I found the reading to be pretty interesting, and it's written in a way that you can actually understand what is being discussed.

Head over to Safari Books Online and check it out. For $17.99 you can read Palm webOS, 1st Editon, Rough Cuts online.

Thanks to Chris for the tip!

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