2 * This file is part of DisOrder
3 * Copyright (C) 2009 Richard Kettlewell
5 * This program is free software: you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation, either version 3 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 /** @file disobedience/multidrag.c
19 * @brief Drag multiple rows of a GtkTreeView
21 * Normally when you start a drag, GtkTreeView sets the selection to just row
22 * you dragged from (because it can't cope with dragging more than one row at a
25 * Disobedience needs more. To implement this it intercepts button-press-event
26 * and button-release event and for clicks that might be the start of drags,
27 * suppresses changes to the selection. A consequence of this is that it needs
28 * to intercept button-release-event too, to restore the effect of the click,
29 * if it turns out not to be drag after all.
31 * The location of the initial click is stored in object data called @c
34 * Inspired by similar code in <a
35 * href="http://code.google.com/p/quodlibet/">Quodlibet</a> (another software
36 * jukebox, albeit as far as I can see a single-user one).
38 #include "disobedience.h"
40 static gboolean
multidrag_selection_block(GtkTreeSelection
attribute((unused
)) *selection
,
41 GtkTreeModel
attribute((unused
)) *model
,
42 GtkTreePath
attribute((unused
)) *path
,
43 gboolean
attribute((unused
)) path_currently_selected
,
45 return *(const gboolean
*)data
;
48 static void block_selection(GtkWidget
*w
, gboolean block
,
50 static const gboolean which
[] = { FALSE
, TRUE
};
51 GtkTreeSelection
*s
= gtk_tree_view_get_selection(GTK_TREE_VIEW(w
));
52 gtk_tree_selection_set_select_function(s
,
53 multidrag_selection_block
,
54 (gboolean
*)&which
[!!block
],
56 // Remember the pointer location
57 int *where
= g_object_get_data(G_OBJECT(w
), "multidrag-where");
59 where
= g_malloc(2 * sizeof (int));
60 g_object_set_data(G_OBJECT(w
), "multidrag-where", where
);
64 // TODO release 'where' when object is destroyed
67 static gboolean
multidrag_button_press_event(GtkWidget
*w
,
68 GdkEventButton
*event
,
69 gpointer
attribute((unused
)) user_data
) {
70 /* By default we assume that anything this button press does should
72 block_selection(w
, TRUE
, -1, -1);
73 /* We are only interested in left-button behavior */
74 if(event
->button
!= 1)
76 /* We are only interested in unmodified clicks (not SHIFT etc) */
77 if(event
->state
& GDK_MODIFIER_MASK
)
79 /* We are only interested if a well-defined path is clicked */
81 if(!gtk_tree_view_get_path_at_pos(GTK_TREE_VIEW(w
),
87 //gtk_widget_grab_focus(w); // TODO why??
88 /* We are only interested if a selected row is clicked */
89 GtkTreeSelection
*s
= gtk_tree_view_get_selection(GTK_TREE_VIEW(w
));
90 if(!gtk_tree_selection_path_is_selected(s
, path
))
92 /* We block subsequent selection changes and remember where the
94 block_selection(w
, FALSE
, event
->x
, event
->y
);
95 return FALSE
; /* propagate */
98 static gboolean
multidrag_button_release_event(GtkWidget
*w
,
99 GdkEventButton
*event
,
100 gpointer
attribute((unused
)) user_data
) {
101 int *where
= g_object_get_data(G_OBJECT(w
), "multidrag-where");
103 /* Did button-press-event do anything? We just check the outcome rather than
104 * going through all the conditions it tests. */
105 if(where
&& where
[0] != -1) {
106 // Remember where the down-click was
107 const int x
= where
[0], y
= where
[1];
108 // Re-allow selections
109 block_selection(w
, TRUE
, -1, -1);
110 if(x
== event
->x
&& y
== event
->y
) {
111 // If the up-click is at the same location as the down-click,
114 GtkTreeViewColumn
*col
;
115 if(gtk_tree_view_get_path_at_pos(GTK_TREE_VIEW(w
),
120 gtk_tree_view_set_cursor(GTK_TREE_VIEW(w
), path
, col
, FALSE
);
124 return FALSE
; /* propagate */
127 /** @brief Allow multi-row drag for @p w
128 * @param w A GtkTreeView widget
130 * Suppresses the restriction of selections when a drag is started.
132 void make_treeview_multidrag(GtkWidget
*w
) {
133 g_signal_connect(w
, "button-press-event",
134 G_CALLBACK(multidrag_button_press_event
), NULL
);
135 g_signal_connect(w
, "button-release-event",
136 G_CALLBACK(multidrag_button_release_event
), NULL
);