Palm OS Programming, 2nd Edition

Gremlins

There are two approaches to testing software, which can often be used in a complementary fashion:

Functionality testing

Careful systematic testing on a feature-by-feature basis, making sure everything works as advertised

Bashing on it

An almost random use of the software to make sure it doesn’t break when stressed

Gremlins does the second sort of testing. Imagine, if you will, a very inquisitive monkey given a Palm OS device with your application on it. The monkey grabs the stylus and starts tapping away. Let’s look at some characteristics of the monkey:

• It’s especially attracted to buttons, pop-ups, and other active items on the screen. It taps in nonactive areas on the screen but not very often; it likes active areas.

• It’s a literate monkey that knows Graffiti. It inputs Graffiti characters—sometimes garbage runs of characters but occasionally fragments of Shakespeare.

• It’s hyperactive. On one of our machines, it can do about 100 events a second.

• It’s well behaved. If told to debug a certain application, it won’t switch out of that application.

You start a Gremlin from the Gremlins dialog box of POSE by selecting New from the Gremlins menu. In this dialog box you specify which Gremlin you want to use and on what application (see Figure 7-14). You get to choose from 1,000 of them, each of which acts slightly differently in terms of the events it generates (the number is a seed to a pseudorandom number generator). Looking at Figure 7-14, you see that we’ve specified our ...