1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
|
/* Gestures
*
* Perform gestures on touchscreens and other input devices. This
* demo reacts to long presses and swipes from all devices, plus
* multi-touch rotate and zoom gestures.
*/
#include <gtk/gtk.h>
static GtkGesture *rotate = NULL;
static GtkGesture *zoom = NULL;
static double swipe_x = 0;
static double swipe_y = 0;
static gboolean long_pressed = FALSE;
static gboolean
touchpad_swipe_gesture_begin (GtkGesture *gesture,
GdkEventSequence *sequence,
GtkWidget *widget)
{
/* Disallow touchscreen events here */
if (sequence != NULL)
gtk_gesture_set_state (gesture, GTK_EVENT_SEQUENCE_DENIED);
return sequence == NULL;
}
static void
swipe_gesture_swept (GtkGestureSwipe *gesture,
double velocity_x,
double velocity_y,
GtkWidget *widget)
{
swipe_x = velocity_x / 10;
swipe_y = velocity_y / 10;
gtk_widget_queue_draw (widget);
}
static void
long_press_gesture_pressed (GtkGestureLongPress *gesture,
double x,
double y,
GtkWidget *widget)
{
long_pressed = TRUE;
gtk_widget_queue_draw (widget);
}
static void
long_press_gesture_end (GtkGesture *gesture,
GdkEventSequence *sequence,
GtkWidget *widget)
{
long_pressed = FALSE;
gtk_widget_queue_draw (widget);
}
static void
rotation_angle_changed (GtkGestureRotate *gesture,
double angle,
double delta,
GtkWidget *widget)
{
gtk_widget_queue_draw (widget);
}
static void
zoom_scale_changed (GtkGestureZoom *gesture,
double scale,
GtkWidget *widget)
{
gtk_widget_queue_draw (widget);
}
static void
drawing_area_draw (GtkDrawingArea *area,
cairo_t *cr,
int width,
int height,
gpointer data)
{
if (swipe_x != 0 || swipe_y != 0)
{
cairo_save (cr);
cairo_set_line_width (cr, 6);
cairo_move_to (cr, width / 2, height / 2);
cairo_rel_line_to (cr, swipe_x, swipe_y);
cairo_set_source_rgba (cr, 1, 0, 0, 0.5);
cairo_stroke (cr);
cairo_restore (cr);
}
if (gtk_gesture_is_recognized (rotate) || gtk_gesture_is_recognized (zoom))
{
cairo_pattern_t *pat;
cairo_matrix_t matrix;
double angle, scale;
double x_center, y_center;
gtk_gesture_get_bounding_box_center (GTK_GESTURE (zoom), &x_center, &y_center);
cairo_get_matrix (cr, &matrix);
cairo_matrix_translate (&matrix, x_center, y_center);
cairo_save (cr);
angle = gtk_gesture_rotate_get_angle_delta (GTK_GESTURE_ROTATE (rotate));
cairo_matrix_rotate (&matrix, angle);
scale = gtk_gesture_zoom_get_scale_delta (GTK_GESTURE_ZOOM (zoom));
cairo_matrix_scale (&matrix, scale, scale);
cairo_set_matrix (cr, &matrix);
cairo_rectangle (cr, -100, -100, 200, 200);
pat = cairo_pattern_create_linear (-100, 0, 200, 0);
cairo_pattern_add_color_stop_rgb (pat, 0, 0, 0, 1);
cairo_pattern_add_color_stop_rgb (pat, 1, 1, 0, 0);
cairo_set_source (cr, pat);
cairo_fill (cr);
cairo_restore (cr);
cairo_pattern_destroy (pat);
}
if (long_pressed)
{
cairo_save (cr);
cairo_arc (cr,
width / 2, height / 2,
50, 0, 2 * G_PI);
cairo_set_source_rgba (cr, 0, 1, 0, 0.5);
cairo_stroke (cr);
cairo_restore (cr);
}
}
GtkWidget *
do_gestures (GtkWidget *do_widget)
{
static GtkWidget *window = NULL;
GtkWidget *drawing_area;
GtkGesture *gesture;
if (!window)
{
window = gtk_window_new ();
gtk_window_set_default_size (GTK_WINDOW (window), 400, 400);
gtk_window_set_title (GTK_WINDOW (window), "Gestures");
g_object_add_weak_pointer (G_OBJECT (window), (gpointer *)&window);
drawing_area = gtk_drawing_area_new ();
gtk_window_set_child (GTK_WINDOW (window), drawing_area);
gtk_drawing_area_set_draw_func (GTK_DRAWING_AREA (drawing_area),
drawing_area_draw,
NULL, NULL);
/* Swipe */
gesture = gtk_gesture_swipe_new ();
g_signal_connect (gesture, "swipe",
G_CALLBACK (swipe_gesture_swept), drawing_area);
gtk_event_controller_set_propagation_phase (GTK_EVENT_CONTROLLER (gesture),
GTK_PHASE_BUBBLE);
gtk_widget_add_controller (drawing_area, GTK_EVENT_CONTROLLER (gesture));
/* 3fg swipe for touchpads */
gesture = g_object_new (GTK_TYPE_GESTURE_SWIPE,
"n-points", 3,
NULL);
g_signal_connect (gesture, "begin",
G_CALLBACK (touchpad_swipe_gesture_begin), drawing_area);
g_signal_connect (gesture, "swipe",
G_CALLBACK (swipe_gesture_swept), drawing_area);
gtk_event_controller_set_propagation_phase (GTK_EVENT_CONTROLLER (gesture),
GTK_PHASE_BUBBLE);
gtk_widget_add_controller (drawing_area, GTK_EVENT_CONTROLLER (gesture));
/* Long press */
gesture = gtk_gesture_long_press_new ();
g_signal_connect (gesture, "pressed",
G_CALLBACK (long_press_gesture_pressed), drawing_area);
g_signal_connect (gesture, "end",
G_CALLBACK (long_press_gesture_end), drawing_area);
gtk_event_controller_set_propagation_phase (GTK_EVENT_CONTROLLER (gesture),
GTK_PHASE_BUBBLE);
gtk_widget_add_controller (drawing_area, GTK_EVENT_CONTROLLER (gesture));
/* Rotate */
rotate = gesture = gtk_gesture_rotate_new ();
g_signal_connect (gesture, "angle-changed",
G_CALLBACK (rotation_angle_changed), drawing_area);
gtk_event_controller_set_propagation_phase (GTK_EVENT_CONTROLLER (gesture),
GTK_PHASE_BUBBLE);
gtk_widget_add_controller (drawing_area, GTK_EVENT_CONTROLLER (gesture));
/* Zoom */
zoom = gesture = gtk_gesture_zoom_new ();
g_signal_connect (gesture, "scale-changed",
G_CALLBACK (zoom_scale_changed), drawing_area);
gtk_event_controller_set_propagation_phase (GTK_EVENT_CONTROLLER (gesture),
GTK_PHASE_BUBBLE);
gtk_widget_add_controller (drawing_area, GTK_EVENT_CONTROLLER (gesture));
}
if (!gtk_widget_get_visible (window))
gtk_widget_show (window);
else
gtk_window_destroy (GTK_WINDOW (window));
return window;
}
|
