Patch: zoom slider in spatial windows

["Rached Ben Mustapha" <benmur gmail com>]

Hi,

I often find myself adjusting the zoom level of spatial windows, based
on the number of files they contain. I tried to implement a zoom
slider, as can be seen in some applications these days [1] [2].

I found the result quite usable, but maybe I'm biased. It clutters
some quite simple windows, for a feature that maybe not so many people
use, however. The zoom images could look better with a tooltip and
prelighting.

Anyway, I thought I'd share, so I attached the patch (screenshot at [3]).

Enjoy,

Rached

[1] http://f-spot.org/Image:Main-window.png
[2] http://www.mac.com/1/images/howto_iphoto_screenshot.jpg
[3] http://benmur.free.fr/files/nautilus-spatial-zoom-slider.png

=== modified file 'src/nautilus-spatial-window.c'
--- src/nautilus-spatial-window.c	2006-12-26 15:28:10 +0000
+++ src/nautilus-spatial-window.c	2007-02-24 15:13:38 +0000
@@ -91,6 +91,7 @@
 	GtkWidget *location_button;
 	GtkWidget *location_label;
 	GtkWidget *location_icon;
+	GtkWidget *zoom_slider;
 
 	GtkWidget *query_editor;
 	
@@ -424,11 +425,87 @@
 }
 
 static void
+zoom_in_image_clicked (GtkWidget *widget, GdkEventButton *event, NautilusView *view)
+{
+	nautilus_view_bump_zoom_level (view, 1);
+}
+
+static void
+zoom_out_image_clicked (GtkWidget *widget, GdkEventButton *event, NautilusView *view)
+{
+	nautilus_view_bump_zoom_level (view, -1);
+}
+
+static void
+update_zoom_slider_value (NautilusView *view, GtkRange *range)
+{
+	NautilusZoomLevel zoom_level;
+
+	zoom_level = nautilus_view_get_zoom_level (view);
+	gtk_range_set_value (range, zoom_level);
+}
+
+static void
+zoom_slider_value_changed (GtkRange *range, NautilusView *view)
+{
+	NautilusZoomLevel zoom_level;
+
+	zoom_level = (NautilusZoomLevel) gtk_range_get_value (range);
+	g_signal_handlers_block_by_func (view, update_zoom_slider_value, range);
+	nautilus_view_zoom_to_level (view, zoom_level);
+	g_signal_handlers_unblock_by_func (view, update_zoom_slider_value, range);
+}
+
+static GtkWidget *
+create_zoom_slider_widget_for_view (NautilusView *view)
+{
+	GtkWidget *box, *scale;
+	GtkWidget *zoom_in_image, *zoom_in_event_box;
+	GtkWidget *zoom_out_image, *zoom_out_event_box;	
+
+	box = gtk_hbox_new (FALSE, 0);
+
+	zoom_in_image = gtk_image_new_from_stock (GTK_STOCK_ZOOM_IN, GTK_ICON_SIZE_MENU);
+	zoom_in_event_box = gtk_event_box_new ();
+	gtk_container_add (GTK_CONTAINER (zoom_in_event_box), zoom_in_image);
+	g_signal_connect (G_OBJECT (zoom_in_event_box), "button-press-event", G_CALLBACK (zoom_in_image_clicked), view);
+
+	scale = gtk_hscale_new_with_range (NAUTILUS_ZOOM_LEVEL_SMALLEST, NAUTILUS_ZOOM_LEVEL_LARGEST, 1);
+	gtk_widget_set_size_request (scale, 100, -1); /* This is arbitrary */
+	gtk_scale_set_draw_value (GTK_SCALE (scale), FALSE);
+	gtk_scale_set_digits (GTK_SCALE (scale), 0);
+	g_object_set (scale, "update-policy", GTK_UPDATE_CONTINUOUS, NULL);
+	g_signal_connect (scale, "value-changed", G_CALLBACK (zoom_slider_value_changed), view);
+	g_signal_connect (view, "zoom_level_changed", G_CALLBACK (update_zoom_slider_value), scale);
+
+	zoom_out_image = gtk_image_new_from_stock (GTK_STOCK_ZOOM_OUT, GTK_ICON_SIZE_MENU);
+	zoom_out_event_box = gtk_event_box_new ();
+	gtk_container_add (GTK_CONTAINER (zoom_out_event_box), zoom_out_image);
+	g_signal_connect (G_OBJECT (zoom_out_event_box), "button-press-event", G_CALLBACK (zoom_out_image_clicked), view);
+
+	gtk_box_pack_end (GTK_BOX (box), zoom_in_event_box, FALSE, FALSE, 0);
+	gtk_box_pack_end (GTK_BOX (box), scale, TRUE, TRUE, 0);
+	gtk_box_pack_end (GTK_BOX (box), zoom_out_event_box, FALSE, FALSE, 0);
+
+	gtk_widget_show_all (box);
+
+	return box;
+}
+
+static void
 real_set_content_view_widget (NautilusWindow *window,
 			      NautilusView *new_view)
 {
 	GtkWidget *widget;
+	GtkWidget *zoom_slider;
+
+	zoom_slider = NAUTILUS_SPATIAL_WINDOW (window)->details->zoom_slider;
 	
+	if (zoom_slider != NULL) {
+		gtk_widget_destroy (zoom_slider);
+		NAUTILUS_SPATIAL_WINDOW (window)->details->zoom_slider = NULL;
+	}
+
 	EEL_CALL_PARENT (NAUTILUS_WINDOW_CLASS, set_content_view_widget,
 			 (window, new_view));
 
@@ -436,6 +513,12 @@
 	
 	gtk_container_add (GTK_CONTAINER (NAUTILUS_SPATIAL_WINDOW (window)->details->content_box),
 			   widget);
+
+	if (nautilus_view_supports_zooming (new_view)) {
+		zoom_slider = create_zoom_slider_widget_for_view (new_view);
+		gtk_box_pack_end (GTK_BOX (window->details->statusbar), zoom_slider, FALSE, FALSE, 0);
+		NAUTILUS_SPATIAL_WINDOW (window)->details->zoom_slider = zoom_slider;
+	}
 }
 
 static void