Java Reference
In-Depth Information
the screen layout. If the
CustomItem
is too large for the screen dimen-
sions, it resizes itself to within those preferred, minimum dimensions
and the
CustomItem
is notified via
sizeChanged()
and
paint()
methods.
Additionally, the developer can use the
Display.getColor(int)
and
Font.getFont(int)
methods to determine the underlying prop-
erties for items already displayed in the form of which the
CustomItem
is a part, to ensure that a consistent appearance is maintained.
DateField
This is an editable component that may be placed upon a
Form
to capture
and display date and time (calendar) values. The item can be added to the
form with or without an initial value. If the value is not set, a call to the
getDate()
method returns
NULL
. The field can handle DATE values,
TIME values, and DATE TIME values.
ImageItem
The
ImageItem
is a reference to a mutable or immutable image that
can be displayed on a
Form
. We look at the
Image
object in detail in
Section 2.3.4. Suffice to say that the
Image
is retrieved from the MIDlet
suite's JAR file in order to be displayed upon the form. This is performed
by calling the following method, in this case from the root directory:
Image image = Image.createImage("/myImage.png");
An
ImageItem
can be rendered in various modes, such as PLAIN,
HYPERLINK, or BUTTON. Please check the MIDP documentation for
more details.
Gauge
This component provides a visual representation of an integer value,
usually formatted as a bar graph. Gauges are used either for specifying a
value between zero and a maximum value, or as a progress or activity
monitor.
Spacer
This blank, non-interactive item with a definable minimum size is used
for allocating flexible amounts of space between items on a form and
gives the developer much more control over the appearance of a form.
The minimum width and height for each spacer can be defined to provide
space between items within a row or between rows of items on the form.
