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:
if ( mouse_pointer_inside_the_scrollable_area) {
$self-> scroll_timer_stop;
} else {
$self-> scroll_timer_start unless $self-> scroll_timer_active;
return unless $self-> scroll_timer_semaphore;
$self-> scroll_timer_semaphore( 0);
}
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:
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
, andvScroll
property keys in profile_default() . A class may provideautoHScroll
andautoVScroll
property keys in profile_default() .A class' init() method must set
{borderWidth}
,{hScroll}
, and{vScroll}
variables to 0 before the initialization, callsetup_indents
method, and then assign the properties from the object profile.If a class provides
autoHScroll
andautoVScroll
properties, these must be set to 0 before the initialization.If a class needs to overload one of
borderWidth
,hScroll
,vScroll
,autoHScroll
, andautoVScroll
properties, it is mandatory to call the inherited properties.A class must implement the scroll bar notification callbacks:
HScroll_Change
andVScroll_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
The reserved method names:
set_h_scroll set_v_scroll insert_bone setup_indents reset_indents borderWidth autoHScroll autoVScroll hScroll vScroll
The reserved widget names:
HScroll VScroll Bone
Properties
- autoHScroll BOOLEAN
-
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. - scrollBarClass STRING = Prima::ScrollBar
-
Create-only property that allows to change scrollbar class
- hScrollBarProfile, vScrollBarProfile HASH
-
Create-only property that allows to change scrollbar parameters when it is being created
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, overloadreset_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.
AUTHOR
Dmitry Karasik, <dmitry@karasik.eu.org>.
SEE ALSO
Prima, Prima::Widget, Prima::InputLine, Prima::Lists, Prima::Edit, Prima::Outlines, Prima::ScrollBar.