From 0fe36a502f9b779ed3eb45f06443c32b125d6849 Mon Sep 17 00:00:00 2001
From: Harald Judt <h.judt@gmx.at>
Date: Sat, 31 Jan 2015 11:22:14 +0100
Subject: Improve keyboard navigation for thunar-tree-view (bug #4519)

Left and right arrow (keypad too) expand/collapse, up and down arrow
work as usual, and the right pane follows the tree view selection.

There is currently a problem with the top-level Desktop item which
would result in opening the item in another subtree (the Desktop
usually resides in /home/user/Desktop). This way, opening the
item automatically would break tree view navigation and this is
bad for user experience. So to open this item, the user has to
press space, enter or keypad enter.
---
 thunar/thunar-tree-view.c | 105 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 105 insertions(+)

diff --git a/thunar/thunar-tree-view.c b/thunar/thunar-tree-view.c
index f987dfc..56da21c 100644
--- a/thunar/thunar-tree-view.c
+++ b/thunar/thunar-tree-view.c
@@ -97,6 +97,8 @@ static gboolean                 thunar_tree_view_button_press_event           (G
                                                                                GdkEventButton          *event);
 static gboolean                 thunar_tree_view_button_release_event         (GtkWidget               *widget,
                                                                                GdkEventButton          *event);
+static gboolean                 thunar_tree_view_key_press_event              (GtkWidget               *widget,
+                                                                               GdkEventKey             *event);
 static void                     thunar_tree_view_drag_data_received           (GtkWidget               *widget,
                                                                                GdkDragContext          *context,
                                                                                gint                     x,
@@ -432,6 +434,9 @@ thunar_tree_view_init (ThunarTreeView *view)
   gtk_tree_selection_set_mode (selection, GTK_SELECTION_SINGLE);
   gtk_tree_selection_set_select_function (selection, thunar_tree_view_selection_func, view, NULL);
 
+  /* custom keyboard handler for better navigation */
+  g_signal_connect (GTK_WIDGET (view), "key_press_event", G_CALLBACK (thunar_tree_view_key_press_event), NULL);
+
   /* enable drop support for the tree view */
   gtk_drag_dest_set (GTK_WIDGET (view), 0, drop_targets, G_N_ELEMENTS (drop_targets),
                      GDK_ACTION_COPY | GDK_ACTION_LINK | GDK_ACTION_MOVE);
@@ -766,6 +771,106 @@ thunar_tree_view_button_release_event (GtkWidget      *widget,
   return (*GTK_WIDGET_CLASS (thunar_tree_view_parent_class)->button_release_event) (widget, event);
 }
 
+static gboolean
+thunar_tree_view_key_press_event(GtkWidget   *widget,
+                                 GdkEventKey *event)
+{
+  ThunarTreeView *tree_view = THUNAR_TREE_VIEW (widget);
+  gboolean stopPropagation = FALSE;
+  GtkTreePath *path;
+
+  /* Get path of currently highlighted item */
+  gtk_tree_view_get_cursor(GTK_TREE_VIEW (tree_view), &path, NULL);
+
+  switch (event->keyval)
+    {
+    case GDK_KEY_Up:
+    case GDK_KP_Up:
+    case GDK_KEY_Down:
+    case GDK_KP_Down:
+      /* the default actions works good, but we want to update the right pane */
+      GTK_WIDGET_CLASS (thunar_tree_view_parent_class)->key_press_event (widget, event);
+
+      /* sync with new tree view selection */
+      gtk_tree_path_free (path);
+      gtk_tree_view_get_cursor (GTK_TREE_VIEW (tree_view), &path, NULL);
+
+      /* The top-level desktop entry is a bit problematic; opening it
+         will usually cause expansion of the home directory where the
+         desktop folder resides. This breaks navigation and is bad for
+         user experience, so do not open the top-level desktop entry
+         automatically.
+       */
+      if (gtk_tree_path_get_depth (path) == 1)
+        {
+          ThunarFile *file;
+          GFile *desktop;
+          GFile *selected;
+
+          file = thunar_tree_view_get_selected_file (tree_view);
+          if (file)
+            {
+              desktop = thunar_g_file_new_for_desktop ();
+              selected = thunar_file_get_file (file);
+
+              /* open only non-desktop top-level items */
+              if (! g_file_equal (desktop, selected))
+                  thunar_tree_view_action_open (tree_view);
+
+              g_object_unref (G_OBJECT (file));
+              g_object_unref (desktop);
+            }
+        }
+      else
+          thunar_tree_view_action_open (tree_view);
+
+      stopPropagation = TRUE;
+      break;
+
+    case GDK_KEY_Left:
+    case GDK_KP_Left:
+      /* if branch is expanded then collapse it */
+      if (gtk_tree_view_row_expanded (GTK_TREE_VIEW (tree_view), path))
+          gtk_tree_view_collapse_row (GTK_TREE_VIEW (tree_view), path);
+
+      else /* if branch is already collapsed then move to parent */
+          if (gtk_tree_path_up (path))
+              gtk_tree_view_set_cursor (GTK_TREE_VIEW (tree_view), path, NULL, FALSE);
+      thunar_tree_view_action_open (tree_view);
+
+      stopPropagation = TRUE;
+      break;
+
+    case GDK_KEY_Right:
+    case GDK_KP_Right:
+      /* if branch is not expanded then expand it */
+      if (!gtk_tree_view_row_expanded (GTK_TREE_VIEW (tree_view), path))
+          gtk_tree_view_expand_row (GTK_TREE_VIEW (tree_view), path, FALSE);
+
+      else /* if branch is already expanded then move to first child */
+        {
+          gtk_tree_path_down (path);
+          gtk_tree_view_set_cursor (GTK_TREE_VIEW (tree_view), path, NULL, FALSE);
+        }
+      thunar_tree_view_action_open (tree_view);
+
+      stopPropagation = TRUE;
+      break;
+
+    case GDK_space:
+    case GDK_Return:
+    case GDK_KP_Enter:
+      thunar_tree_view_open_selection (tree_view);
+      stopPropagation = TRUE;
+      break;
+    }
+
+  gtk_tree_path_free (path);
+  if (stopPropagation)
+      gtk_widget_grab_focus (widget);
+
+  return stopPropagation;
+}
 
 
 static void
-- 
2.2.2