Section: User Contributed Perl Documentation (3)Updated: 2009-02-24Local indexUp
NAME
Prima::IntUtils - internal functions
DESCRIPTION
The module provides packages, containing common functionality
for some standard classes. The packages are designed as a code
containers, not as widget classes, and are to be used as
secondary ascendants in the widget inheritance declaration.
Prima::MouseScroller
Implements routines for emulation of auto repeating mouse events.
A code inside "MouseMove" callback can be implemented by
the following scheme:
The class uses a semaphore "{mouseTransaction}", which should
be set to non-zero if a widget is in mouse capture state, and set
to zero or "undef" otherwise.
The class starts an internal timer, which sets a semaphore and
calls "MouseMove" notification when triggered. The timer is
assigned the timeouts, returned by "Prima::Application::get_scroll_rate"
( see ``get_scroll_rate'' in Prima::Application ).
Methods
scroll_timer_active
Returns a boolean value indicating if the internal timer is started.
scroll_timer_semaphore [ VALUE ]
A semaphore, set to 1 when the internal timer was triggered. It is advisable
to check the semaphore state to discern a timer-generated event from
the real mouse movement. If VALUE is specified, it is assigned to the semaphore.
scroll_timer_start
Starts the internal timer.
scroll_timer_stop
Stops the internal timer.
Prima::IntIndents
Provides the common functionality for the widgets that delegate part of their
surface to the border elements. A list box can be of an example, where its
scroll bars and 3-d borders are such elements.
Properties
indents ARRAY
Contains four integers, specifying the breadth of decoration elements for
each side. The first integer is width of the left element, the second - height
of the lower element, the third - width of the right element, the fourth - height
of the upper element.
The property can accept and return the array either as a four scalars, or as
an anonymous array of four scalars.
Methods
get_active_area [ TYPE = 0, WIDTH, HEIGHT ]
Calculates and returns the extension of the area without the border elements,
or the active area.
The extension are related to the current size of a widget, however, can be
overridden by specifying WIDTH and HEIGHT. TYPE is an integer, indicating
the type of calculation:
TYPE = 0
Returns four integers, defining the area in the inclusive-exclusive coordinates.
TYPE = 1
Returns four integers, defining the area in the inclusive-inclusive coordinates.
TYPE = 2
Returns two integers, the size of the area.
Prima::GroupScroller
The class is used for widgets that contain optional scroll bars, and provides means for
their maintenance. The class is the descendant of Prima::IntIndents, and adjusts
the indents property when scrollbars are shown or hidden, or borderWidth is changed.
The class does not provide range selection for the scrollbars; the descentant classes
must implement that.
The descendant classes must follow the guidelines:
•
A class must provide "borderWidth", "hScroll", and "vScroll" property keys in profile_default() .
A class may provide "autoHScroll" and "autoVScroll" property keys in profile_default() .
•
A class' init() method must set "{borderWidth}", "{hScroll}", and "{vScroll}"
variables to 0 before the initialization, call "setup_indents" method,
and then assign the properties from the object profile.
If a class provides "autoHScroll" and "autoVScroll" properties, these must be set to
0 before the initialization.
•
If a class needs to overload one of "borderWidth", "hScroll", "vScroll",
"autoHScroll", and "autoVScroll" properties,
it is mandatory to call the inherited properties.
•
A class must implement the scroll bar notification callbacks: "HScroll_Change" and "VScroll_Change".
•
A class must not use the reserved variable names, which are:
{borderWidth} - internal borderWidth storage
{hScroll} - internal hScroll value storage
{vScroll} - internal vScroll value storage
{hScrollBar} - pointer to the horizontal scroll bar
{vScrollBar} - pointer to the vertical scroll bar
{bone} - rectangular widget between the scrollbars
{autoHScroll} - internal autoHScroll value storage
{autoVScroll} - internal autoVScroll value storage
Selects if the horizontal scrollbar is to be shown and hidden dynamically,
depending on the widget layout.
autoVScroll BOOLEAN
Selects if the vertical scrollbar is to be shown and hidden dynamically,
depending on the widget layout.
borderWidth INTEGER
Width of 3d-shade border around the widget.
Recommended default value: 2
hScroll BOOLEAN
Selects if the horizontal scrollbar is visible. If it is, "{hScrollBar}"
points to it.
vScroll BOOLEAN
Selects if the vertical scrollbar is visible. If it is, "{vScrollBar}"
points to it.
Properties
setup_indents
The method is never called directly; it should be called whenever widget
layout is changed so that indents are affected. The method is a request
to recalculate indents, depending on the widget layout.
The method is not reentrant; to receive this callback and update the widget
layout, that in turn can result in more "setup_indents" calls, overload
"reset_indents" .
reset_indents
Called after "setup_indents" is called and internal widget layout is updated,
to give a chance to follow-up the layout changes.