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the Applet Creates Button Images
For
the best looking buttons, you should ideally create a button bar image for each
button state. Unfortunately, this is usually not practical. Not only does it
take time to create a button bar image for each and every button state, but it
also increases the amount of data that the applet must retrieve when it is
initializing. On an intranet, this might not be an issue, but transfer speeds on
the Internet are typically much slower, and the more image files that the applet
must load the slower the initialization process will be.
In order to
relieve some of the burden of image file creation from the button bar designer,
and in order to lower the image loading bandwidth requirements, the Ultimate
Button BarTM will automatically create,
or synthesize, images for button states where a predefined image file
for the button state does not exist.
Here is what the Ultimate
Button BarTM does to create an image for
button states with no image file (note that it might not be possible to specify
an image file for some of these button states, depending upon the applet's
implementation):
 |
"base" Button State
This is
the image that is displayed when a active button is "at rest" (i.e.,
the mouse is not within the button's boundaries). An "active" button
is a button that is not disabled.
An image file for the "base"
button state must always be specified, so
Ultimate Button BarTM will never
automatically create an image for this state. |
|
"mouseOver"
Button State
This is the image that is displayed when the mouse is
moved within an active button's boundaries, and when the button is not "stuck"
down ("sticky" buttons do not apply to applets).
If an image
file is not specified for this button state, then the "base" image
file is used for the "mouseOver" button state, and a grayscale version
of the "base" image file is created for use as the new "base"
image. |
|
"mouseOver2"
Button State
The "mouseOver2" image file is not really a
button state, but rather is the second frame of animation for animated buttons.
A
"mouseOver2" image is never synthesized: if the image file is
missing, then no animation will take place for the buttons on the button bar. |
|
"mouseDown"
Button State
The "mouseDown" button image is displayed when
the mouse button is clicked while within the boundaries of an active button on
the button bar. The "mouseDown" image is displayed as long as the
mouse button continues to be held down.
If an image file for the "mouseDown"
button state is not specified, and if borders are drawn for the buttons, then
the button will be drawn with an inverse border (to give the illusion that the
button has been depressed). If borders are not drawn for the buttons, then the "mouseOver"
image will be brightened (or "lightened") and used as the "mouseDown"
image. |
|
"mouseDownOver"
Button State
This state does not apply to applets.
The "mouseDownOver"
state is when a "sticky" button is "stuck" down and the
mouse is moved within the button's boundaries.
If an image file is not
specified for the "mouseDownOver" button state, then the "mouseDown"
image is brightened (or lightened). |
|
"buttonsDisabled"
Button State
This is the image that is displayed when a button is
disabled.
If an image file for the "buttonsDisabled" button
state is not provided, then the "buttonsDisabled" image will be
created by darkening (or "dimming") the "base" button image. |
Note that you can override the automatic creation of
an image for a button state with an existing image file. For instance, if you
are not using a "mouseOver" image but you do not want the Ultimate
Button BarTM to create a grayscale image
for the "base" button state (i.e., you want to use the "base"
image file for both the "base" state and the "mouseOver"
state), then you can simply specify the "base" image file for the "mouseOver"
image file too. The Ultimate Button BarTM
is smart enough to realize that it should not load the "base" image
file twice, but rather it will load the image file once and use it internally
twice: once for the "base" state and once for the "mouseOver"
state. |
