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To make the application more appealing, the size of the sphere displayed
on the Stage is also changed in proportion to the selected diameter. The
user interface for the application is illustrated in Figure 5-26.
Click the left and right arrows
to change the diameter of the
sphere.
The size of the sphere
changes with the selected
diameter.
The application automatically
calculates the volume (V ) and
surface area (S).
Figure 5-26: User interface for the sphere application
The application contains three sprites: the two arrow buttons (named
Up and Down) and the sphere image (named Sphere). The scripts associated
with the two buttons broadcast a message to indicate that they have been
clicked, as shown in Figure 5-27.
Script for the Script for the
Down sprite Up sprite
Figure 5-27: Scripts for the Up and Down sprites
The Sphere sprite has nine costumes that represent spheres with diam-
eters 1, 1.25, 1.5, 1.75, ... , 3. When this sprite receives the Up or Down broad-
cast messages, it executes the scripts shown in Figure 5-28.
Figure 5-28: Scripts triggered by the Up and Down messages
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