3 * Use transparent background on GdkWindows to create a shadow effect on a GtkOverlay widget.
8 #define SHADOW_OFFSET_X 7
9 #define SHADOW_OFFSET_Y 7
10 #define SHADOW_RADIUS 5
13 draw_shadow_box (cairo_t *cr,
18 cairo_pattern_t *pattern;
19 double x0, x1, x2, x3;
20 double y0, y1, y2, y3;
24 x2 = rect.x + rect.width - radius;
25 x3 = rect.x + rect.width;
29 y2 = rect.y + rect.height - radius;
30 y3 = rect.y + rect.height;
32 /* Fill non-border part */
33 cairo_set_source_rgba (cr, 0, 0, 0, transparency);
35 x1, y1, x2 - x1, y2 - y1);
40 pattern = cairo_pattern_create_linear (0, y0, 0, y1);
42 cairo_pattern_add_color_stop_rgba (pattern, 0.0, 0.0, 0, 0, 0.0);
43 cairo_pattern_add_color_stop_rgba (pattern, 1.0, 0.0, 0, 0, transparency);
45 cairo_set_source (cr, pattern);
46 cairo_pattern_destroy (pattern);
55 pattern = cairo_pattern_create_linear (0, y2, 0, y3);
57 cairo_pattern_add_color_stop_rgba (pattern, 0.0, 0.0, 0, 0, transparency);
58 cairo_pattern_add_color_stop_rgba (pattern, 1.0, 0.0, 0, 0, 0.0);
60 cairo_set_source (cr, pattern);
61 cairo_pattern_destroy (pattern);
70 pattern = cairo_pattern_create_linear (x0, 0, x1, 0);
72 cairo_pattern_add_color_stop_rgba (pattern, 0.0, 0.0, 0, 0, 0.0);
73 cairo_pattern_add_color_stop_rgba (pattern, 1.0, 0.0, 0, 0, transparency);
75 cairo_set_source (cr, pattern);
76 cairo_pattern_destroy (pattern);
85 pattern = cairo_pattern_create_linear (x2, 0, x3, 0);
87 cairo_pattern_add_color_stop_rgba (pattern, 0.0, 0.0, 0, 0, transparency);
88 cairo_pattern_add_color_stop_rgba (pattern, 1.0, 0.0, 0, 0, 0.0);
90 cairo_set_source (cr, pattern);
91 cairo_pattern_destroy (pattern);
100 pattern = cairo_pattern_create_radial (x1, y1, 0,
103 cairo_pattern_add_color_stop_rgba (pattern, 0.0, 0.0, 0, 0, transparency);
104 cairo_pattern_add_color_stop_rgba (pattern, 1.0, 0.0, 0, 0, 0.0);
106 cairo_set_source (cr, pattern);
107 cairo_pattern_destroy (pattern);
116 pattern = cairo_pattern_create_radial (x2, y1, 0,
119 cairo_pattern_add_color_stop_rgba (pattern, 0.0, 0.0, 0, 0, transparency);
120 cairo_pattern_add_color_stop_rgba (pattern, 1.0, 0.0, 0, 0, 0.0);
122 cairo_set_source (cr, pattern);
123 cairo_pattern_destroy (pattern);
132 pattern = cairo_pattern_create_radial (x1, y2, 0,
135 cairo_pattern_add_color_stop_rgba (pattern, 0.0, 0.0, 0, 0, transparency);
136 cairo_pattern_add_color_stop_rgba (pattern, 1.0, 0.0, 0, 0, 0.0);
138 cairo_set_source (cr, pattern);
139 cairo_pattern_destroy (pattern);
148 pattern = cairo_pattern_create_radial (x2, y2, 0,
151 cairo_pattern_add_color_stop_rgba (pattern, 0.0, 0.0, 0, 0, transparency);
152 cairo_pattern_add_color_stop_rgba (pattern, 1.0, 0.0, 0, 0, 0.0);
154 cairo_set_source (cr, pattern);
155 cairo_pattern_destroy (pattern);
164 draw_callback (GtkWidget *widget,
170 gtk_widget_get_allocation (widget, &rect);
171 rect.x += SHADOW_OFFSET_X;
172 rect.y += SHADOW_OFFSET_Y;
173 rect.width -= SHADOW_OFFSET_X;
174 rect.height -= SHADOW_OFFSET_Y;
177 rect, SHADOW_RADIUS, 0.4);
183 do_transparent (GtkWidget *do_widget)
185 static GtkWidget *window = NULL;
194 GdkRGBA transparent = {0.1, 0, 0, 0};
196 window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
197 gtk_window_set_screen (GTK_WINDOW (window),
198 gtk_widget_get_screen (do_widget));
199 gtk_window_set_default_size (GTK_WINDOW (window),
202 g_signal_connect (window, "destroy",
203 G_CALLBACK (gtk_widget_destroyed), &window);
205 gtk_window_set_title (GTK_WINDOW (window), "Transparent");
206 gtk_container_set_border_width (GTK_CONTAINER (window), 0);
208 view = gtk_text_view_new ();
210 sw = gtk_scrolled_window_new (NULL, NULL);
211 gtk_scrolled_window_set_policy (GTK_SCROLLED_WINDOW (sw),
212 GTK_POLICY_AUTOMATIC,
213 GTK_POLICY_AUTOMATIC);
214 gtk_container_add (GTK_CONTAINER (sw), view);
216 overlay = gtk_overlay_new ();
217 gtk_container_add (GTK_CONTAINER (overlay), sw);
218 gtk_container_add (GTK_CONTAINER (window), overlay);
220 gtk_widget_override_background_color (overlay, 0, &transparent);
222 align = gtk_alignment_new (0.0, 0.0, 0.0, 0.0);
223 gtk_alignment_set_padding (GTK_ALIGNMENT (align),
224 0, SHADOW_OFFSET_Y, 0, SHADOW_OFFSET_X);
225 g_signal_connect (align, "draw", G_CALLBACK (draw_callback), NULL);
227 entry = gtk_entry_new ();
228 gtk_container_add (GTK_CONTAINER (align), entry);
230 gtk_overlay_add_overlay (GTK_OVERLAY (overlay), align);
231 gtk_widget_set_halign (align, GTK_ALIGN_CENTER);
232 gtk_widget_set_valign (align, GTK_ALIGN_START);
234 gtk_widget_show_all (overlay);
237 if (!gtk_widget_get_visible (window))
239 gtk_widget_show (window);
243 gtk_widget_destroy (window);