[baobab/reroot-view: 41/48] Delay showing the result page until the scan is completed

[Stefano Facchini <sfacchini src gnome org>]

commit 8a6e8bebea5c74a245dcf3d4aa8796e687618166
Author: Stefano Facchini <stefano facchini gmail com>
Date:   Thu Jun 18 17:57:33 2020 +0200

    Delay showing the result page until the scan is completed
    
    It seems that the combination GtkTreeView + GtkModelFilter chokes on directories
    with many entries.
    
    Show a simple "scanning page" instead.

 data/ui/baobab-main-window.ui | 15 ++++++++++++++-
 src/baobab-window.vala        | 19 ++++++++++++++-----
 2 files changed, 28 insertions(+), 6 deletions(-)
---
diff --git a/data/ui/baobab-main-window.ui b/data/ui/baobab-main-window.ui
index bc596ec..9a348f6 100644
--- a/data/ui/baobab-main-window.ui
+++ b/data/ui/baobab-main-window.ui
@@ -198,7 +198,6 @@
             <object class="GtkStack" id="main_stack">
               <property name="visible">True</property>
               <property name="can_focus">False</property>
-              <property name="transition_type">slide-left-right</property>
               <child>
                 <object class="GtkGrid" id="home_page">
                   <property name="can_focus">False</property>
@@ -220,6 +219,20 @@
                   </child>
                  </object>
               </child>
+              <child>
+                <object class="GtkGrid" id="scanning_page">
+                  <property name="visible">True</property>
+                  <property name="orientation">vertical</property>
+                  <property name="halign">center</property>
+                  <property name="valign">center</property>
+                  <child>
+                    <object class="GtkLabel" id="scanning_label">
+                      <property name="visible">True</property>
+                      <property name="label">Scanning…</property>
+                    </object>
+                  </child>
+                </object>
+              </child>
               <child>
                 <object class="GtkGrid" id="result_page">
                   <property name="visible">True</property>
diff --git a/src/baobab-window.vala b/src/baobab-window.vala
index e968d9d..9eef70e 100644
--- a/src/baobab-window.vala
+++ b/src/baobab-window.vala
@@ -110,6 +110,8 @@ namespace Baobab {
         [GtkChild]
         private Gtk.Widget home_page;
         [GtkChild]
+        private Gtk.Widget scanning_page;
+        [GtkChild]
         private Gtk.Widget result_page;
         [GtkChild]
         private Gtk.InfoBar infobar;
@@ -556,22 +558,29 @@ namespace Baobab {
         void set_ui_state (Gtk.Widget child, bool busy) {
             menu_button.visible = (child == home_page);
             reload_button.visible = (child == result_page);
-            back_button.visible = (child == result_page);
+            back_button.visible = (child == result_page) || (child == scanning_page);
 
             set_busy (busy);
 
+            header_bar.custom_title = null;
             if (child == home_page) {
                 var action = lookup_action ("reload") as SimpleAction;
                 action.set_enabled (false);
                 header_bar.title = _("Devices & Locations");
-                header_bar.custom_title = null;
             } else {
                 var action = lookup_action ("reload") as SimpleAction;
                 action.set_enabled (true);
                 header_bar.title = active_location.name;
-                header_bar.custom_title = pathbar;
+                if (child == result_page) {
+                    header_bar.custom_title = pathbar;
+                }
             }
 
+            if (child == scanning_page || child == result_page) {
+                main_stack.transition_type = Gtk.StackTransitionType.CROSSFADE;
+            } else {
+                main_stack.transition_type = Gtk.StackTransitionType.SLIDE_LEFT_RIGHT;
+            }
             main_stack.visible_child = child;
         }
 
@@ -622,6 +631,7 @@ namespace Baobab {
                 }
             }
 
+            reroot_treeview (new Gtk.TreePath.first ());
             set_chart_location (active_location);
             set_ui_state (result_page, false);
 
@@ -656,10 +666,9 @@ namespace Baobab {
             scan_completed_handler = scanner.completed.connect (scanner_completed);
 
             clear_message ();
-            set_ui_state (result_page, true);
+            set_ui_state (scanning_page, true);
 
             scanner.scan (force);
-            reroot_when_scanner_not_empty ();
         }
 
         public void scan_directory (File directory, ScanFlags flags=ScanFlags.NONE) {