Use key files for tracking widget states.

Each EShellView now maintains a GKeyFile for recording disposable widget
state such as tree view path expansion, scroll bar positions, combo box
selections, etc.  The EShellView records changes to the key file to
~/.evolution/<shell-backend>/config/state, and automatically restores
the GKeyFile at startup.

Currently only the mailer uses the key file, but it's intended to serve
all shell views.  It replaces the use of Camel "cmeta" files, as well as
"et-expanded-*" and "folder-tree-expand-state.xml" files.

Also, the mailer's folder tree model now includes a column for tracking
which sidebar folders are expanded.  Folder tree widgets appearing in
dialog windows can copy the sidebar's expanded state using
em_folder_tree_clone_expanded().

4 files changed, 204 insertions, 4 deletions

diff --git a/shell/e-shell-content.c b/shell/e-shell-content.c
index 216520fbb4..2fc9569bd2 100644
--- a/shell/e-shell-content.c
+++ b/shell/e-shell-content.c
@@ -24,6 +24,7 @@
 #include <glib/gi18n.h>
 
 #include "e-util/e-binding.h"
+#include "e-util/e-util.h"
 #include "filter/rule-editor.h"
 #include "widgets/misc/e-action-combo-box.h"
 #include "widgets/misc/e-hinted-entry.h"
@@ -36,6 +37,10 @@
 	(G_TYPE_INSTANCE_GET_PRIVATE \
 	((obj), E_TYPE_SHELL_CONTENT, EShellContentPrivate))
 
+#define STATE_KEY_SEARCH_FILTER		"SearchFilter"
+#define STATE_KEY_SEARCH_SCOPE		"SearchScope"
+#define STATE_KEY_SEARCH_TEXT		"SearchText"
+
 struct _EShellContentPrivate {
 
 	gpointer shell_view;  /* weak pointer */
@@ -55,8 +60,6 @@ struct _EShellContentPrivate {
 	GtkWidget *search_entry;
 	GtkWidget *scope_label;
 	GtkWidget *scope_combo_box;
-
-	GtkStateType search_state;
 };
 
 enum {
@@ -138,7 +141,10 @@ action_search_execute_cb (GtkAction *action,
 	/* Direct the focus away from the search entry, so that a
 	 * focus-in event is required before the text can be changed.
 	 * This will reset the entry to the appropriate visual state. */
-	gtk_widget_grab_focus (gtk_bin_get_child (GTK_BIN (shell_content)));
+	widget = gtk_bin_get_child (GTK_BIN (shell_content));
+	if (GTK_IS_PANED (widget))
+		widget = gtk_paned_get_child1 (GTK_PANED (widget));
+	gtk_widget_grab_focus (widget);
 }
 
 static void
@@ -897,7 +903,6 @@ shell_content_init (EShellContent *shell_content)
 	gtk_label_set_mnemonic_widget (label, widget);
 	gtk_box_pack_start (box, widget, TRUE, TRUE, 0);
 	shell_content->priv->search_entry = g_object_ref (widget);
-	shell_content->priv->search_state = GTK_STATE_NORMAL;
 	gtk_widget_show (widget);
 
 	g_signal_connect_swapped (
@@ -1486,3 +1491,69 @@ exit:
 	g_object_unref (rule);
 	gtk_widget_destroy (dialog);
 }
+
+void
+e_shell_content_restore_state (EShellContent *shell_content,
+                               const gchar *group_name)
+{
+	EShellView *shell_view;
+	EShellWindow *shell_window;
+	GKeyFile *key_file;
+	GtkAction *action;
+	GtkWidget *widget;
+	const gchar *key;
+	gchar *string;
+
+	g_return_if_fail (E_IS_SHELL_CONTENT (shell_content));
+	g_return_if_fail (group_name != NULL);
+
+	shell_view = e_shell_content_get_shell_view (shell_content);
+	shell_window = e_shell_view_get_shell_window (shell_view);
+	key_file = e_shell_view_get_state_key_file (shell_view);
+
+	/* Changing the combo boxes triggers searches, so block
+	 * the search action until the state is fully restored. */
+	action = e_shell_window_get_action (shell_window, "search-execute");
+	gtk_action_block_activate (action);
+
+	key = STATE_KEY_SEARCH_FILTER;
+	string = g_key_file_get_string (key_file, group_name, key, NULL);
+	if (string != NULL && *string != '\0')
+		action = e_shell_window_get_action (shell_window, string);
+	else
+		action = NULL;
+	if (action != NULL)
+		gtk_action_activate (action);
+	else {
+		/* Pick the first combo box item. */
+		widget = shell_content->priv->filter_combo_box;
+		gtk_combo_box_set_active (GTK_COMBO_BOX (widget), 0);
+	}
+	g_free (string);
+
+	key = STATE_KEY_SEARCH_SCOPE;
+	string = g_key_file_get_string (key_file, group_name, key, NULL);
+	if (string != NULL && *string != '\0')
+		action = e_shell_window_get_action (shell_window, string);
+	else
+		action = NULL;
+	if (action != NULL)
+		gtk_action_activate (action);
+	else {
+		/* Pick the first combo box item. */
+		widget = shell_content->priv->scope_combo_box;
+		gtk_combo_box_set_active (GTK_COMBO_BOX (widget), 0);
+	}
+	g_free (string);
+
+	key = STATE_KEY_SEARCH_TEXT;
+	string = g_key_file_get_string (key_file, group_name, key, NULL);
+	e_shell_content_set_search_text (shell_content, string);
+	g_free (string);
+
+	action = e_shell_window_get_action (shell_window, "search-execute");
+	gtk_action_unblock_activate (action);
+
+	/* Now execute the search. */
+	gtk_action_activate (action);
+}
diff --git a/shell/e-shell-content.h b/shell/e-shell-content.h
index af2799c7d4..8e754fff26 100644
--- a/shell/e-shell-content.h
+++ b/shell/e-shell-content.h
@@ -140,6 +140,8 @@ void		e_shell_content_run_edit_searches_dialog
 						(EShellContent *shell_content);
 void		e_shell_content_run_save_search_dialog
 						(EShellContent *shell_content);
+void		e_shell_content_restore_state	(EShellContent *shell_content,
+						 const gchar *group_name);
 
 G_END_DECLS
 
diff --git a/shell/e-shell-view.c b/shell/e-shell-view.c
index cf89442c7c..d1ab1af4a4 100644
--- a/shell/e-shell-view.c
+++ b/shell/e-shell-view.c
@@ -33,10 +33,15 @@
 	(G_TYPE_INSTANCE_GET_PRIVATE \
 	((obj), E_TYPE_SHELL_VIEW, EShellViewPrivate))
 
+#define STATE_SAVE_TIMEOUT_SECONDS 3
+
 struct _EShellViewPrivate {
 
 	gpointer shell_window;  /* weak pointer */
 
+	GKeyFile *state_key_file;
+	guint state_save_source_id;
+
 	gchar *title;
 	gchar *view_id;
 	gint page_num;
@@ -118,6 +123,72 @@ shell_view_update_view_id (EShellView *shell_view,
 }
 
 static void
+shell_view_load_state (EShellView *shell_view)
+{
+	EShellBackend *shell_backend;
+	GKeyFile *key_file;
+	const gchar *config_dir;
+	gchar *filename;
+	GError *error = NULL;
+
+	shell_backend = e_shell_view_get_shell_backend (shell_view);
+	config_dir = e_shell_backend_get_config_dir (shell_backend);
+	filename = g_build_filename (config_dir, "state", NULL);
+
+	/* XXX Should do this asynchronously. */
+	key_file = shell_view->priv->state_key_file;
+	g_key_file_load_from_file (key_file, filename, 0, &error);
+
+	if (error == NULL)
+		goto exit;
+
+	if (!g_error_matches (error, G_FILE_ERROR, G_FILE_ERROR_NOENT))
+		g_warning ("%s", error->message);
+
+	g_error_free (error);
+
+exit:
+	g_free (filename);
+}
+
+static void
+shell_view_save_state (EShellView *shell_view)
+{
+	EShellBackend *shell_backend;
+	GKeyFile *key_file;
+	const gchar *config_dir;
+	gchar *contents;
+	gchar *filename;
+	GError *error = NULL;
+
+	shell_backend = e_shell_view_get_shell_backend (shell_view);
+	config_dir = e_shell_backend_get_config_dir (shell_backend);
+	filename = g_build_filename (config_dir, "state", NULL);
+
+	/* XXX Should do this asynchronously. */
+	key_file = shell_view->priv->state_key_file;
+	contents = g_key_file_to_data (key_file, NULL, NULL);
+	g_file_set_contents (filename, contents, -1, &error);
+	g_free (contents);
+
+	if (error != NULL) {
+		g_warning ("%s", error->message);
+		g_error_free (error);
+	}
+
+	g_free (filename);
+}
+
+static gboolean
+shell_view_state_timeout_cb (EShellView *shell_view)
+{
+	shell_view_save_state (shell_view);
+	shell_view->priv->state_save_source_id = 0;
+
+	return FALSE;
+}
+
+static void
 shell_view_emit_toggled (EShellView *shell_view)
 {
 	g_signal_emit (shell_view, signals[TOGGLED], 0);
@@ -267,6 +338,13 @@ shell_view_dispose (GObject *object)
 
 	priv = E_SHELL_VIEW_GET_PRIVATE (object);
 
+	/* Expedite any pending state saves. */
+	if (priv->state_save_source_id > 0) {
+		g_source_remove (priv->state_save_source_id);
+		priv->state_save_source_id = 0;
+		shell_view_save_state (E_SHELL_VIEW (object));
+	}
+
 	if (priv->shell_window != NULL) {
 		g_object_remove_weak_pointer (
 			G_OBJECT (priv->shell_window), &priv->shell_window);
@@ -304,6 +382,8 @@ shell_view_finalize (GObject *object)
 
 	priv = E_SHELL_VIEW_GET_PRIVATE (object);
 
+	g_key_file_free (priv->state_key_file);
+
 	g_free (priv->title);
 	g_free (priv->view_id);
 
@@ -330,6 +410,8 @@ shell_view_constructed (GObject *object)
 
 	e_plugin_ui_register_manager (ui_manager, id, shell_view);
 
+	shell_view_load_state (shell_view);
+
 	/* Invoke factory methods. */
 
 	widget = class->new_shell_content (shell_view);
@@ -598,6 +680,7 @@ shell_view_init (EShellView *shell_view,
 	size_group = gtk_size_group_new (GTK_SIZE_GROUP_VERTICAL);
 
 	shell_view->priv = E_SHELL_VIEW_GET_PRIVATE (shell_view);
+	shell_view->priv->state_key_file = g_key_file_new ();
 	shell_view->priv->size_group = size_group;
 }
 
@@ -947,6 +1030,48 @@ e_shell_view_get_shell_taskbar (EShellView *shell_view)
 }
 
 /**
+ * e_shell_view_get_state_key_file:
+ * @shell_view: an #EShellView
+ *
+ * Returns the #GKeyFile holding widget state data for @shell_view.
+ *
+ * Returns: the #GKeyFile for @shell_view
+ **/
+GKeyFile *
+e_shell_view_get_state_key_file (EShellView *shell_view)
+{
+	g_return_val_if_fail (E_IS_SHELL_VIEW (shell_view), NULL);
+
+	return shell_view->priv->state_key_file;
+}
+
+/**
+ * e_shell_view_set_state_dirty:
+ * @shell_view: an #EShellView
+ *
+ * Marks the widget state data as modified (or "dirty") and schedules it
+ * to be saved to disk after a short delay.  The delay caps the frequency
+ * of saving to disk.
+ **/
+void
+e_shell_view_set_state_dirty (EShellView *shell_view)
+{
+	guint source_id;
+
+	g_return_if_fail (E_IS_SHELL_VIEW (shell_view));
+
+	/* If a timeout is already scheduled, do nothing. */
+	if (shell_view->priv->state_save_source_id > 0)
+		return;
+
+	source_id = g_timeout_add_seconds (
+		STATE_SAVE_TIMEOUT_SECONDS, (GSourceFunc)
+		shell_view_state_timeout_cb, shell_view);
+
+	shell_view->priv->state_save_source_id = source_id;
+}
+
+/**
  * e_shell_view_update_actions:
  * @shell_view: an #EShellView
  *
diff --git a/shell/e-shell-view.h b/shell/e-shell-view.h
index a3ca595fba..b323839478 100644
--- a/shell/e-shell-view.h
+++ b/shell/e-shell-view.h
@@ -171,6 +171,8 @@ EShellContent *	e_shell_view_get_shell_content	(EShellView *shell_view);
 EShellSidebar *	e_shell_view_get_shell_sidebar	(EShellView *shell_view);
 EShellTaskbar *	e_shell_view_get_shell_taskbar	(EShellView *shell_view);
 EShellWindow *	e_shell_view_get_shell_window	(EShellView *shell_view);
+GKeyFile *	e_shell_view_get_state_key_file	(EShellView *shell_view);
+void		e_shell_view_set_state_dirty	(EShellView *shell_view);
 void		e_shell_view_update_actions	(EShellView *shell_view);
 void		e_shell_view_show_popup_menu	(EShellView *shell_view,
 						 const gchar *widget_path,