/src/wrappers/gtk/library/gtk_range.e

  1indexing
  2	description: "GtkRange -- Base class for widgets which visualize an adjustment."
  3	copyright: "[
  4					Copyright (C) 2006 eiffel-libraries team, GTK+ team
  5					
  6					This library is free software; you can redistribute it and/or
  7					modify it under the terms of the GNU Lesser General Public License
  8					as published by the Free Software Foundation; either version 2.1 of
  9					the License, or (at your option) any later version.
 10					
 11					This library is distributed in the hope that it will be useful, but
 12					WITHOUT ANY WARRANTY; without even the implied warranty of
 13					MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 14					Lesser General Public License for more details.
 15
 16					You should have received a copy of the GNU Lesser General Public
 17					License along with this library; if not, write to the Free Software
 18					Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 19					02110-1301 USA
 20				]"
 21	date: "$Date:$"
 22	revision: "$Revision:$"
 23
 24deferred class GTK_RANGE
 25
 26inherit
 27	GTK_WIDGET
 28	GTK_RANGE_EXTERNALS
 29
 30feature -- The adjustment
 31
 32	adjustment: GTK_ADJUSTMENT is
 33			-- the GtkAdjustment which is the "model" object for
 34			-- GtkRange. It contains the current value of this range
 35			-- object.
 36		local
 37			factory: G_OBJECT_EXPANDED_FACTORY [GTK_ADJUSTMENT]
 38		do
 39			Result := factory.unreffed_wrapper_or_void (gtk_range_get_adjustment (handle))
 40			-- GTK documentation says "See gtk_range_set_adjustment() for
 41			-- details. The return value does not have a reference added,
 42			-- so should not be unreferenced." Instead we just add a
 43			-- reference to the adjustment, because there will be an
 44			-- effective refence on the Eiffel side
 45			-- Result.ref
 46		ensure
 47			valid_adjustment: Result /= Void
 48		end
 49
 50	set_adjustment (an_adjustment: GTK_ADJUSTMENT) is
 51			-- Sets the adjustment to be used as the "model" object for
 52			-- this range widget. The adjustment indicates the current
 53			-- range value, the minimum and maximum range values, the
 54			-- step/page increments used for keybindings and scrolling,
 55			-- and the page size. The page size is normally 0 for
 56			-- GtkScale and nonzero for GtkScrollbar, and indicates the
 57			-- size of the visible area of the widget being scrolled. The
 58			-- page size affects the size of the scrollbar slider.
 59		require valid_adjustment: an_adjustment /= Void
 60		do
 61			gtk_range_set_adjustment (handle, an_adjustment.handle)
 62		end
 63
 64feature -- update policy
 65	set_continous_update_policy is
 66			-- Sets the update policy for the range. GTK_UPDATE_CONTINUOUS
 67			-- means that anytime the range slider is moved, the range value
 68			-- will change and the value_changed signal will be
 69			-- emitted. 
 70		do
 71			gtk_range_set_update_policy (handle, gtk_update_continuous)
 72		ensure is_update_policy_continous
 73		end
 74
 75	is_update_policy_continous: BOOLEAN is
 76			-- Sets the update policy for the range. GTK_UPDATE_CONTINUOUS
 77			-- means that anytime the range slider is moved, the range value
 78			-- will change and the value_changed signal will be
 79			-- emitted. 
 80		do
 81			Result := (gtk_range_get_update_policy (handle) = gtk_update_continuous)
 82		end
 83
 84	set_discontinous_update_policy is
 85			-- Sets the update policy for the range. GTK_UPDATE_DELAYED
 86			-- means that the value will be updated after a brief timeout
 87			-- where no slider motion occurs, so updates are spaced by a
 88			-- short time rather than continuous.
 89		do
 90			gtk_range_set_update_policy (handle, gtk_update_discontinuous)
 91		ensure is_update_policy_discontinous
 92		end
 93
 94	is_update_policy_discontinous: BOOLEAN is
 95			-- Sets the update policy for the range. GTK_UPDATE_DELAYED
 96			-- means that the value will be updated after a brief timeout
 97			-- where no slider motion occurs, so updates are spaced by a
 98			-- short time rather than continuous.
 99		do
100			Result := (gtk_range_get_update_policy (handle) = gtk_update_discontinuous)
101		end
102
103	set_delayed_update_policy is
104			-- Sets the update policy for the
105			-- range. GTK_UPDATE_DISCONTINUOUS means that the value will
106			-- only be updated when the user releases the button and ends
107			-- the slider drag operation.
108		do
109			gtk_range_set_update_policy (handle, gtk_update_delayed)
110		ensure is_update_policy_delayed
111		end
112
113	is_update_policy_delayed: BOOLEAN is
114			-- Sets the update policy for the
115			-- range. GTK_UPDATE_DISCONTINUOUS means that the value will
116			-- only be updated when the user releases the button and ends
117			-- the slider drag operation.
118		do
119			Result := (gtk_range_get_update_policy (handle) = gtk_update_delayed)
120		end
121
122feature -- Inverted-ness
123
124	is_inverted: BOOLEAN is
125			-- Is the range inverted? An inverted direction slider moves
126			-- to increase range value.
127		do
128			Result := (gtk_range_get_inverted (handle)).to_boolean
129		end
130
131	set_inverted is
132			-- Ranges normally move from lower to higher values as the
133			-- slider moves from top to bottom or left to right. Inverted
134			-- ranges have higher values at the top or on the right
135			-- rather than on the bottom or left.
136		do
137			gtk_range_set_inverted (handle,1)
138		ensure is_inverted
139		end
140
141	set_normal is
142			-- Ranges normally move from lower to higher values as the
143			-- slider moves from top to bottom or left to right. Inverted
144			-- ranges have higher values at the top or on the right
145			-- rather than on the bottom or left.
146		do
147			gtk_range_set_inverted (handle,0)
148		ensure not is_inverted
149		end
150
151feature -- value
152
153	value: REAL_64 is
154			-- the current value of the range.
155		do
156			Result := gtk_range_get_value (handle)
157		end
158
159	set_value (a_value: REAL_64) is
160			-- Sets the current value of the range; if `a_value' is
161			-- outside the minimum or maximum range values, it will be
162			-- clamped to fit inside them. The range emits the
163			-- "value_changed" signal if the value changes.
164		do
165			gtk_range_set_value (handle, a_value)
166		end
167
168feature -- increments
169	set_increments (a_step, a_page: REAL) is
170			-- Sets the step and page sizes for the range. The step size
171			-- is used when the user clicks the GtkScrollbar arrows or
172			-- moves GtkScale via arrow keys. The page size is used for
173			-- example when moving via Page Up or Page Down keys.
174		do
175			gtk_range_set_increments (handle, a_step, a_page)
176		end
177
178feature -- range
179
180	set_range (a_min,a_max: REAL_64) is
181			-- Sets the allowable values in the GtkRange, and clamps the
182			-- range value to be between min and max. (If the range has a
183			-- non-zero page size, it is clamped between min and max -
184			-- page-size.) -- `a_min': minimum range value; `a_max':
185			-- maximum range value
186		do
187			gtk_range_set_range (handle, a_min, a_max)
188		end
189
190
191	-- Note: The "adjustment", "inverted" property
192
193feature -- TODO: The "update-policy" property
194	--   "update-policy"        GtkUpdateType         : Read / Write
195	
196	-- How the range should be updated on the screen.
197	
198	-- Default value: GTK_UPDATE_CONTINUOUS
199	-- Style Property Details
200
201feature -- TODO: The "arrow-displacement-x" style property
202--   "arrow-displacement-x" gint                  : Read
203
204-- How far in the x direction to move the arrow when the button is depressed.
205
206-- Default value: 0
207feature -- TODO: The "arrow-displacement-y" style property
208--   "arrow-displacement-y" gint                  : Read
209
210-- How far in the y direction to move the arrow when the button is depressed.
211
212-- Default value: 0
213feature -- TODO: The "slider-width" style property
214--   "slider-width"         gint                  : Read
215
216-- Width of scrollbar or scale thumb.
217
218-- Allowed values: >= 0
219
220-- Default value: 14
221feature -- TODO: The "stepper-size" style property
222--   "stepper-size"         gint                  : Read
223
224-- Length of step buttons at ends.
225
226-- Allowed values: >= 0
227
228-- Default value: 14
229feature -- TODO: The "stepper-spacing" style property
230--   "stepper-spacing"      gint                  : Read
231
232-- Spacing between step buttons and thumb.
233
234-- Allowed values: >= 0
235
236-- Default value: 0
237feature -- TODO: The "trough-border" style property
238--   "trough-border"        gint                  : Read
239
240-- Spacing between thumb/steppers and outer trough bevel.
241
242-- Allowed values: >= 0
243
244-- Default value: 1
245
246feature -- TODO: Signal Details
247
248-- The "adjust-bounds" signal
249
250-- void        user_function                  (GtkRange *range,
251--                                             gdouble arg1,
252--                                             gpointer user_data);
253
254-- range : 	the object which received the signal.
255-- arg1 : 	
256-- user_data : 	user data set when the signal handler was connected.
257
258feature -- The "change-value" signal
259
260		-- Since 2.6
261		-- The `change-value' signal is emitted when a scroll action is
262		-- performed on a range. It allows an application to determine the type of
263		-- scroll event that occurred and the resultant new value. The application
264		-- can handle the event itself and return True to prevent further
265		-- processing. Or, by returning False, it can pass the event to other
266		-- handlers until the default GTK+ handler is reached.
267
268		-- The value parameter is unrounded. An application that overrides the
269		-- `change-value' signal is responsible for clamping the value to the
270		-- desired number of decimal digits; the default GTK+ handler clamps the
271		-- value based on range->round_digits.
272
273		-- It is not possible to use delayed update policies in an overridden
274		-- `change-value' handler.
275
276	change_value_signal_name: STRING is "change-value"
277		-- gboolean    user_function                  (GtkRange *range,
278		--                                             GtkScrollType scroll,
279		--                                             gdouble value,
280		--                                             gpointer user_data);
281
282	enable_on_change_value is
283			-- Connects "change-value" signal to `on_change_value' feature.
284		do
285			connect (Current, change_value_signal_name, $on_change_value)
286		end
287
288	on_change_value: INTEGER is
289			-- Built-in change-value signal handler; empty by design; redefine it.
290		do
291		end
292
293	connect_agent_to_change_value_signal (a_function: FUNCTION[ANY, TUPLE [REAL, INTEGER, GTK_RANGE], BOOLEAN]) is
294			-- range : the range that received the signal.
295			-- scroll: the type of scroll action that was performed.
296			-- value : the new value resulting from the scroll action.
297			-- returns:	True to prevent other handlers from being invoked for the signal.
298			--          False to propagate the signal further.
299		require
300			valid_function: a_function /= Void
301			wrapper_is_stored: is_eiffel_wrapper_stored
302		local
303			change_value_callback: CHANGE_VALUE_CALLBACK
304		do
305			create change_value_callback.make
306			change_value_callback.connect (Current, a_function)
307		end
308
309-- The "move-slider" signal
310
311-- void        user_function                  (GtkRange *range,
312--                                             GtkScrollType arg1,
313--                                             gpointer user_data);
314
315-- Virtual function that moves the slider. Used for keybindings.
316-- range : 	the GtkRange
317-- arg1 : 	
318-- user_data : 	user data set when the signal handler was connected.
319
320feature -- The "value-changed" signal
321-- void        user_function                  (GtkRange *range,
322--                                             gpointer user_data);
323
324-- Emitted when the range value changes.
325-- range : 	the GtkRange
326-- user_data : 	user data set when the signal handler was connected.
327
328	value_changed_signal_name: STRING is "value-changed"
329
330	on_value_changed is
331			-- Built-in value_changed signal handler; empty by design; redefine it.
332		do
333		end
334
335	enable_on_value_changed is
336			-- Connects "value_changed" signal to `on_value_changed' feature.
337		do
338			connect (Current, value_changed_signal_name, $on_value_changed)
339		end
340
341	connect_agent_to_value_changed_signal (a_procedure: PROCEDURE [ANY, TUPLE[GTK_RANGE]]) is
342		require valid_procedure: a_procedure /= Void
343		local value_changed_callback: VALUE_CHANGED_CALLBACK
344		do
345			create value_changed_callback.make
346			value_changed_callback.connect (Current, a_procedure)
347		end
348
349end