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Diffstat (limited to 'ieditor_gesture.pl')
| -rw-r--r-- | ieditor_gesture.pl | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/ieditor_gesture.pl b/ieditor_gesture.pl new file mode 100644 index 0000000..fe5d68c --- /dev/null +++ b/ieditor_gesture.pl @@ -0,0 +1,134 @@ +/* + * This file contains minor patches to the select_editor_text_gesture + * class included with XPCE to bring the behavior closer to UI + * standards. + * + */ + +:- use_module(library(pce)). + +% Override the default @editor_recogniser. This affects the default +% editor class too! + +ieditor_gesture_override :- + free(@editor_recogniser), + new(@editor_recogniser, handler_group(new(ieditor_gesture))). + +:- pce_begin_class(ieditor_gesture, select_editor_text_gesture). + +% Get the index of the clicked character -- but if the user clicked +% close to the next character, get that character's index instead. +% +% (If the mouse is dragged above the editor, though, the pointer's x +% position should not be accounted for whatsoever.) + +index(_, Ev, Index) :<- + "Calculate index of clicked character.":: + get(Ev, receiver, Editor), + get(Editor, image, Image), + get(Image, index, Ev, Index0), + get(Ev, y, Y_ev), + ( Y_ev > 1, + get(Image, character_position, Index0, Point1), + get(Image, character_position, Index0 + 1, Point2), + get(Ev, x, X_ev), + get(Image, x, X_image), + get(Point1, x, X1), + get(Point2, x, X2), + D1 is X_ev - X_image - X1, + D2 is X2 - (X_ev - X_image), + D1 > abs(D2), + Index is Index0 + 1 + ; Index = Index0 + ). + +initiate(G, Ev:event) :-> + "Set caret and prepare for selectiong":: + send(G, slot, down_position, Ev?position), + get(Ev, receiver, Editor), + send(G, slot, editor, Editor), + get(G, index, Ev, Index), % Use sane index. + send(Editor, caret, Index), + get(Ev, multiclick, Multi), + selection_unit(Multi, Unit), + send(G, slot, unit, Unit), + ( Multi == single + -> send(G, slot, origin, Index), + send(G, selecting, @off) + ; send(G, selecting, @on) + ). + +selection_unit(single, character). +selection_unit(double, word). +selection_unit(triple, line). + +drag(G, Ev:event) :-> + "Extend the selection if selecting":: + get(Ev, receiver, Editor), + ( ( get(G, selecting, @on) + -> true + ; get(G, down_position, DownPos), + get(Ev, position, EvPos), + get(DownPos, distance, EvPos, D), + D > 5 % Default is 25. + -> send(G, selecting, @on) + ) + -> ( get(G, index, Ev, Index) % Use sane index. + -> ( get(G, unit, character) % Fix mark after char selection. + -> get(G, selection_save_mark, Editor, M), + send(Editor, selection_extend, Index), + send(Editor, mark, M) + ; send(Editor, selection_extend, Index) + ) + ; true + ) + ; true + ). + +selection_save_mark(G, Editor, M) :<- + ( ( get(Editor, mark_status, active) + ; get(G, selecting, @on) + ) + -> get(Editor, mark, M) % Already selecting. + ; get(Editor, caret, C), + send(Editor, selection_origin, C), % Start new selection. + M = C + ). + +:- pce_end_class. + +/* Based on code included with XPCE --- The SWI-Prolog GUI toolkit + + Original file: xpce/prolog/boot/pce_editor.pl + + Author: Jan Wielemaker and Anjo Anjewierden + E-mail: jan@swi.psy.uva.nl + WWW: http://www.swi.psy.uva.nl/projects/xpce/ + Copyright (c) 1985-2002, University of Amsterdam + All rights reserved. + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions + are met: + + 1. Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + + 2. Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in + the documentation and/or other materials provided with the + distribution. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER + CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN + ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + POSSIBILITY OF SUCH DAMAGE. +*/ |