New for MIDP 2.0

New for MIDP 2.0

We have marked a number of topics in this chapter as New! with an icon in the book margin. The user interface capabilities of the high-level user interface have been dramatically improved to allow increased control by the application developer over the layout and visual elements.

Class Display has been improved to allow:

• the querying of the colors used by the device for normal and highlighted colors for foreground, background, and borders (see the getColor method),

• the activation of the backlight and vibrator of the device as added effects to gain the attention of the user (see the vibrate and flashBacklight methods),

• the querying of the best width and height for Images used in Lists, Choice elements, and Alerts (see the getBestImageWidth and getBestImageHeight methods),

• the querying of the number of alpha levels supported (see the numAlphaLevels method), and

• the querying of the border style used for highlighted and normal elements (see the getBorderStyle method).

Class Displayable has been extended to allow:

• a title and Ticker to be set for any Displayable including Canvas (see the setTitle and setTicker methods), and

• the querying of the width and height of any Displayable; previously this was only possible for Canvas objects (see the getWidth and getHeight methods).

Abstract Commands have been enhanced to provide:

• the ability to create Commands with both a short label and long label; which one is used depends on the context and the available display area (see the constructor and getLonglabel methods).