[geary/mjog/responsive-layout-fixes: 22/23] client: Ensure keyboard focus is not lost when main window leaflets fold

[Michael Gratton <mjog src gnome org>]

commit 1667a7b2da079d43b48f57b7cf1812ad9ea97cbe
Author: Michael Gratton <mike vee net>
Date:   Wed Apr 14 09:17:30 2021 +1000

    client: Ensure keyboard focus is not lost when main window leaflets fold
    
    See GNOME/libhandy#179

 .../application/application-main-window.vala       | 31 +++++++++++++++++++---
 ui/application-main-window.ui                      |  2 ++
 2 files changed, 29 insertions(+), 4 deletions(-)
---
diff --git a/src/client/application/application-main-window.vala 
b/src/client/application/application-main-window.vala
index 53a48cf0e..ff87acd56 100644
--- a/src/client/application/application-main-window.vala
+++ b/src/client/application/application-main-window.vala
@@ -2113,10 +2113,33 @@ public class Application.MainWindow :
         update_conversation_actions(
             ConversationCount.for_size(selected)
         );
-        if (this.has_composer &&
-            this.outer_leaflet.folded &&
-            (this.is_folder_list_shown || this.is_conversation_list_shown)) {
-            close_composer(false, false);
+        if (this.outer_leaflet.folded) {
+            // Ensure something useful gets the keyboard focus, given
+            // GNOME/libhandy#179
+            if (this.is_conversation_list_shown) {
+                this.conversation_list_view.grab_focus();
+            } else if (this.is_folder_list_shown) {
+                this.folder_list.grab_focus();
+            }
+
+            // Close any open composer that is no longer visible
+            if (this.has_composer &&
+                (this.is_folder_list_shown || this.is_conversation_list_shown)) {
+                close_composer(false, false);
+            }
+        }
+    }
+
+    [GtkCallback]
+    private void on_inner_leaflet_changed() {
+        if (this.inner_leaflet.folded) {
+            // Ensure something useful gets the keyboard focus, given
+            // GNOME/libhandy#179
+            if (this.is_conversation_list_shown) {
+                this.conversation_list_view.grab_focus();
+            } else if (this.is_folder_list_shown) {
+                this.folder_list.grab_focus();
+            }
         }
     }
 
diff --git a/ui/application-main-window.ui b/ui/application-main-window.ui
index 289c60131..374c14c26 100644
--- a/ui/application-main-window.ui
+++ b/ui/application-main-window.ui
@@ -30,6 +30,8 @@
                     <property name="hexpand_set">True</property>
                     <property name="can_swipe_back">True</property>
                     <property name="transition_type">over</property>
+                    <signal name="notify::folded" handler="on_inner_leaflet_changed" swapped="no"/>
+                    <signal name="notify::visible-child" handler="on_inner_leaflet_changed" swapped="no"/>
                     <child>
                       <object class="GtkBox" id="folder_box">
                         <property name="visible">True</property>