[eog] Extend print preview to scale with plus and minus from keyboard as well

[Felix Riemann <friemann src gnome org>]

commit 982a69b0888fc5d0ac3427166aa5cca30b0e97b4
Author: Felix Riemann <friemann gnome org>
Date:   Wed Jan 4 21:08:27 2012 +0100

    Extend print preview to scale with plus and minus from keyboard as well
    
    https://bugzilla.gnome.org/show_bug.cgi?id=495716

 src/eog-print-image-setup.c |   68 +++++++++++++++++++++++++++++++++++++++---
 src/eog-print-preview.c     |   47 ++++++-----------------------
 src/eog-print-preview.h     |    6 +++-
 3 files changed, 78 insertions(+), 43 deletions(-)
---
diff --git a/src/eog-print-image-setup.c b/src/eog-print-image-setup.c
index c3f38cb..7cbcf6c 100644
--- a/src/eog-print-image-setup.c
+++ b/src/eog-print-image-setup.c
@@ -634,16 +634,72 @@ on_preview_image_moved (EogPrintPreview *preview,
 	gtk_spin_button_set_value (GTK_SPIN_BUTTON (priv->top), y);
 }
 
-static void
-on_preview_image_scaled (EogPrintPreview *preview,
-			 gpointer user_data)
+static gboolean
+on_preview_image_scrolled (GtkWidget *widget,
+			   GdkEventScroll *event,
+			   gpointer user_data)
 {
 	EogPrintImageSetupPrivate *priv = EOG_PRINT_IMAGE_SETUP (user_data)->priv;
+	EogPrintPreview *preview = EOG_PRINT_PREVIEW (widget);
 	gfloat scale;
 
 	scale = eog_print_preview_get_scale (preview);
 
+	if (!eog_print_preview_point_in_image_area (preview,
+						    event->x, event->y))
+	{
+		return FALSE;
+	}
+
+	switch (event->direction) {
+	case GDK_SCROLL_UP:
+		/* scale up */
+		scale *= 1.1;
+		break;
+	case GDK_SCROLL_DOWN:
+		/* scale down */
+		scale *= 0.9;
+		break;
+	default:
+		return FALSE;
+		break;
+	}
+
 	gtk_range_set_value (GTK_RANGE (priv->scaling), 100*scale);
+
+	return TRUE;
+}
+
+static gboolean
+on_preview_image_key_pressed (GtkWidget *widget,
+			      GdkEventKey *event,
+			      gpointer user_data)
+{
+	EogPrintImageSetupPrivate *priv = EOG_PRINT_IMAGE_SETUP (user_data)->priv;
+	EogPrintPreview *preview = EOG_PRINT_PREVIEW (widget);
+	gfloat scale;
+
+	scale = eog_print_preview_get_scale (preview);
+
+	switch (event->keyval) {
+	case GDK_KEY_KP_Add:
+	case GDK_KEY_plus:
+		/* scale up */
+		scale *= 1.1;
+		break;
+	case GDK_KEY_KP_Subtract:
+	case GDK_KEY_minus:
+		/* scale down */
+		scale *= 0.9;
+		break;
+	default:
+		return FALSE;
+		break;
+	}
+
+	gtk_range_set_value (GTK_RANGE (priv->scaling), 100*scale);
+
+	return TRUE;
 }
 
 /* Function taken from gtkprintunixdialog.c */
@@ -831,8 +887,10 @@ connect_signals (EogPrintImageSetup *setup)
 			  G_CALLBACK (on_scale_format_value), NULL);
 	g_signal_connect (G_OBJECT (priv->preview), "image-moved",
 			  G_CALLBACK (on_preview_image_moved), setup);
-	g_signal_connect (G_OBJECT (priv->preview), "image-scaled",
-			  G_CALLBACK (on_preview_image_scaled), setup);
+	g_signal_connect (G_OBJECT (priv->preview), "scroll-event",
+			  G_CALLBACK (on_preview_image_scrolled), setup);
+	g_signal_connect (G_OBJECT (priv->preview), "key-press-event",
+			  G_CALLBACK (on_preview_image_key_pressed), setup);
 }
 
 static void
diff --git a/src/eog-print-preview.c b/src/eog-print-preview.c
index 4fed6c7..f30befc 100644
--- a/src/eog-print-preview.c
+++ b/src/eog-print-preview.c
@@ -477,7 +477,6 @@ static gboolean button_press_event_cb   (GtkWidget *widget, GdkEventButton *bev,
 static gboolean button_release_event_cb (GtkWidget *widget, GdkEventButton *bev, gpointer user_data);
 static gboolean motion_notify_event_cb  (GtkWidget *widget, GdkEventMotion *mev, gpointer user_data);
 static gboolean key_press_event_cb      (GtkWidget *widget, GdkEventKey *event, gpointer user_data);
-static gboolean scroll_event_cb         (GtkWidget *widget, GdkEventScroll *event, gpointer user_data);
 
 static gboolean draw_cb (GtkDrawingArea *drawing_area, cairo_t *cr, gpointer  user_data);
 static void size_allocate_cb (GtkWidget *widget, GtkAllocation *allocation, gpointer user_data);
@@ -558,9 +557,6 @@ eog_print_preview_new (void)
 	g_signal_connect (area, "size-allocate",
 			  G_CALLBACK (size_allocate_cb), preview);
 
-	g_signal_connect (G_OBJECT (area), "scroll-event",
-			  G_CALLBACK (scroll_event_cb), preview);
-
 	return GTK_WIDGET (preview);
 }
 
@@ -638,6 +634,16 @@ press_inside_image_area (EogPrintPreview *preview,
 	return FALSE;
 }
 
+gboolean
+eog_print_preview_point_in_image_area (EogPrintPreview *preview,
+				       guint x,
+				       guint y)
+{
+	g_return_val_if_fail (EOG_IS_PRINT_PREVIEW (preview), FALSE);
+
+	return press_inside_image_area (preview, x, y);
+}
+
 static void
 create_image_scaled (EogPrintPreview *preview)
 {
@@ -976,39 +982,6 @@ motion_notify_event_cb (GtkWidget      *widget,
 	return FALSE;
 }
 
-static gboolean
-scroll_event_cb (GtkWidget *widget,
-		 GdkEventScroll *event,
-		 gpointer user_data)
-{
-	g_assert (EOG_IS_PRINT_PREVIEW (user_data));
-
-	EogPrintPreview *preview = EOG_PRINT_PREVIEW (user_data);
-
-	if (press_inside_image_area (EOG_PRINT_PREVIEW (user_data),
-				     event->x, event->y))
-	{
-		gfloat scale;
-		gfloat multiplier;
-
-		g_object_get (preview, "image-scale", &scale, NULL);
-
-		switch (event->direction) {
-		case GDK_SCROLL_UP:
-			/* scale up */
-			multiplier = 1.1;
-			break;
-		case GDK_SCROLL_DOWN:
-			/* scale down */
-			multiplier = 0.9;
-
-		}
-		eog_print_preview_set_scale (preview, CLAMP (scale * multiplier, 0., 1.));
-	}
-	return TRUE;
-}
-
-
 static void
 size_allocate_cb (GtkWidget *widget,
 		  GtkAllocation *allocation,
diff --git a/src/eog-print-preview.h b/src/eog-print-preview.h
index 4395400..fbe80c9 100644
--- a/src/eog-print-preview.h
+++ b/src/eog-print-preview.h
@@ -76,9 +76,13 @@ void         eog_print_preview_set_image_position  (EogPrintPreview *preview,
 						    gdouble          y);
 
 G_GNUC_INTERNAL
+gboolean     eog_print_preview_point_in_image_area (EogPrintPreview *preview,
+						    guint            x,
+						    guint            y);
+G_GNUC_INTERNAL
 void         eog_print_preview_set_scale           (EogPrintPreview *preview,
 						    gfloat           scale);
-
+G_GNUC_INTERNAL
 gfloat       eog_print_preview_get_scale           (EogPrintPreview *preview);
 
 G_END_DECLS