[gnome-software] Add transitions to the screenshots

[Matthias Clasen <matthiasc src gnome org>]

commit a6b9df66c34b065aed0ada87f522caddd8b4ea90
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Oct 7 22:43:44 2013 -0400

    Add transitions to the screenshots
    
    For now, just use GtkStack to get simple cross-fade
    transitions.

 src/gs-screenshot-image.c |   34 ++++++++++++++++++++--------------
 src/screenshot-image.ui   |   45 +++++++++++++++++++++++++++------------------
 2 files changed, 47 insertions(+), 32 deletions(-)
---
diff --git a/src/gs-screenshot-image.c b/src/gs-screenshot-image.c
index 9faf568..1d58f9a 100644
--- a/src/gs-screenshot-image.c
+++ b/src/gs-screenshot-image.c
@@ -31,16 +31,18 @@
 struct _GsScreenshotImagePrivate
 {
        GsScreenshot    *screenshot;
-       GtkWidget       *box;
+       GtkWidget       *stack;
        GtkWidget       *box_error;
        GtkWidget       *button;
-       GtkWidget       *image;
+       GtkWidget       *image1;
+       GtkWidget       *image2;
        GtkWidget       *label_error;
        GtkWidget       *spinner;
        SoupSession     *session;
        gchar           *cachedir;
        gchar           *filename;
        guint            spinner_id;
+        const gchar     *current_image;
 };
 
 G_DEFINE_TYPE_WITH_PRIVATE (GsScreenshotImage, gs_screenshot_image, GTK_TYPE_BIN)
@@ -93,11 +95,9 @@ gs_screenshot_image_set_error (GsScreenshotImage *ssimg, const gchar *message)
                priv->spinner_id = 0;
        }
 
-       gtk_widget_set_visible (priv->image, FALSE);
-       gtk_widget_set_visible (priv->spinner, FALSE);
-       gtk_widget_set_visible (priv->box_error, TRUE);
+       gtk_stack_set_visible_child_name (GTK_STACK (priv->stack), "error");
        gtk_label_set_label (GTK_LABEL (priv->label_error), message);
-       gtk_widget_get_size_request (priv->box, &width, &height);
+       gtk_widget_get_size_request (priv->stack, &width, &height);
        if (width < 200)
                gtk_widget_hide (priv->label_error);
        else
@@ -121,11 +121,17 @@ gs_screenshot_show_image (GsScreenshotImage *ssimg)
 
        /* stop loading */
        gtk_spinner_stop (GTK_SPINNER (priv->spinner));
-       gtk_widget_set_visible (priv->spinner, FALSE);
 
        /* show icon */
-       gtk_image_set_from_file (GTK_IMAGE (priv->image), priv->filename);
-       gtk_widget_set_visible (priv->image, TRUE);
+       if (g_strcmp0 (priv->current_image, "image1") == 0) {
+               gtk_image_set_from_file (GTK_IMAGE (priv->image2), priv->filename);
+               gtk_stack_set_visible_child_name (GTK_STACK (priv->stack), "image2");
+               priv->current_image = "image2";
+       } else {
+               gtk_image_set_from_file (GTK_IMAGE (priv->image1), priv->filename);
+               gtk_stack_set_visible_child_name (GTK_STACK (priv->stack), "image1");
+               priv->current_image = "image1";
+       }
 }
 
 /**
@@ -187,7 +193,7 @@ gs_screenshot_image_show_spinner (gpointer user_data)
        GsScreenshotImagePrivate *priv;
        priv = gs_screenshot_image_get_instance_private (ssimg);
        gtk_spinner_start (GTK_SPINNER (priv->spinner));
-       gtk_widget_set_visible (priv->spinner, TRUE);
+       gtk_stack_set_visible_child_name (GTK_STACK (priv->stack), "spinner");
        return FALSE;
 }
 
@@ -218,8 +224,7 @@ gs_screenshot_image_set_screenshot (GsScreenshotImage *ssimg,
        if (priv->screenshot)
                g_object_unref (priv->screenshot);
        priv->screenshot = screenshot;
-       gtk_widget_set_size_request (priv->box, width, height);
-       gtk_widget_set_visible (priv->image, FALSE);
+       gtk_widget_set_size_request (priv->stack, width, height);
 
        /* test if size specific cachdir exists */
        url = gs_screenshot_get_url (screenshot, width, height);
@@ -365,10 +370,11 @@ gs_screenshot_image_class_init (GsScreenshotImageClass *klass)
        gtk_widget_class_set_template_from_resource (widget_class,
                                                     "/org/gnome/software/screenshot-image.ui");
 
-       gtk_widget_class_bind_template_child_private (widget_class, GsScreenshotImage, box);
+       gtk_widget_class_bind_template_child_private (widget_class, GsScreenshotImage, stack);
        gtk_widget_class_bind_template_child_private (widget_class, GsScreenshotImage, button);
        gtk_widget_class_bind_template_child_private (widget_class, GsScreenshotImage, spinner);
-       gtk_widget_class_bind_template_child_private (widget_class, GsScreenshotImage, image);
+       gtk_widget_class_bind_template_child_private (widget_class, GsScreenshotImage, image1);
+       gtk_widget_class_bind_template_child_private (widget_class, GsScreenshotImage, image2);
        gtk_widget_class_bind_template_child_private (widget_class, GsScreenshotImage, box_error);
        gtk_widget_class_bind_template_child_private (widget_class, GsScreenshotImage, label_error);
 }
diff --git a/src/screenshot-image.ui b/src/screenshot-image.ui
index 45870a5..1f38c06 100644
--- a/src/screenshot-image.ui
+++ b/src/screenshot-image.ui
@@ -10,36 +10,47 @@
           <class name="screenshot-image"/>
         </style>
         <child>
-          <object class="GtkBox" id="box">
+          <object class="GtkStack" id="stack">
             <property name="visible">True</property>
             <property name="can_focus">False</property>
-            <property name="orientation">vertical</property>
+            <property name="transition-type">crossfade</property>
             <child>
-              <object class="GtkSpinner" id="spinner">
-                <property name="width_request">16</property>
-                <property name="height_request">16</property>
+              <object class="GtkImage" id="image1">
+                <property name="visible">True</property>
+                <property name="halign">center</property>
+                <property name="valign">center</property>
+              </object>
+              <packing>
+                <property name="name">image1</property>
+              </packing>
+            </child>
+            <child>
+              <object class="GtkImage" id="image2">
                 <property name="visible">True</property>
+                <property name="halign">center</property>
+                <property name="valign">center</property>
               </object>
               <packing>
-                <property name="expand">True</property>
-                <property name="fill">False</property>
-                <property name="position">0</property>
+                <property name="name">image2</property>
               </packing>
             </child>
             <child>
-              <object class="GtkImage" id="image">
-                <property name="visible">False</property>
-                <property name="stock">gtk-missing-image</property>
+              <object class="GtkSpinner" id="spinner">
+                <property name="visible">True</property>
+                <property name="width_request">16</property>
+                <property name="height_request">16</property>
+                <property name="halign">center</property>
+                <property name="valign">center</property>
               </object>
               <packing>
-                <property name="expand">True</property>
-                <property name="fill">False</property>
-                <property name="position">1</property>
+                <property name="name">spinner</property>
               </packing>
             </child>
             <child>
               <object class="GtkBox" id="box_error">
-                <property name="visible">False</property>
+                <property name="visible">True</property>
+                <property name="halign">center</property>
+                <property name="valign">center</property>
                 <property name="orientation">vertical</property>
                 <property name="spacing">4</property>
                 <child>
@@ -68,9 +79,7 @@
                 </child>
               </object>
               <packing>
-                <property name="expand">True</property>
-                <property name="fill">False</property>
-                <property name="position">2</property>
+                <property name="name">error</property>
               </packing>
             </child>
           </object>