path: root/modules/calendar/e-task-shell-content.c

/*
 * e-task-shell-content.c
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) version 3.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with the program; if not, see <http://www.gnu.org/licenses/>
 *
 *
 * Copyright (C) 1999-2008 Novell, Inc. (www.novell.com)
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "e-task-shell-content.h"

#include <glib/gi18n.h>

#include "e-util/e-selection.h"
#include "shell/e-shell-utils.h"
#include "widgets/menus/gal-view-etable.h"
#include "widgets/misc/e-paned.h"
#include "widgets/misc/e-preview-pane.h"

#include "calendar/gui/comp-util.h"
#include "calendar/gui/e-cal-component-preview.h"
#include "calendar/gui/e-cal-model-tasks.h"

#define E_TASK_SHELL_CONTENT_GET_PRIVATE(obj) \
    (G_TYPE_INSTANCE_GET_PRIVATE \
    ((obj), E_TYPE_TASK_SHELL_CONTENT, ETaskShellContentPrivate))

#define E_TASK_TABLE_DEFAULT_STATE \
    "<?xml version=\"1.0\"?>" \
    "<ETableState>" \
    "  <column source=\"13\"/>" \
    "  <column source=\"14\"/>" \
    "  <column source=\"9\"/>" \
    "  <column source=\"5\"/>" \
    "  <grouping/>" \
    "</ETableState>"

struct _ETaskShellContentPrivate {
    GtkWidget *paned;
    GtkWidget *task_table;
    GtkWidget *preview_pane;

    ECalModel *task_model;
    GalViewInstance *view_instance;
    GtkOrientation orientation;

    gchar *current_uid;

    guint preview_visible   : 1;
};

enum {
    PROP_0,
    PROP_MODEL,
    PROP_ORIENTATION,
    PROP_PREVIEW_VISIBLE
};

G_DEFINE_DYNAMIC_TYPE_EXTENDED (
    ETaskShellContent,
    e_task_shell_content,
    E_TYPE_SHELL_CONTENT,
    0,
    G_IMPLEMENT_INTERFACE_DYNAMIC (
        GTK_TYPE_ORIENTABLE, NULL))

static void
task_shell_content_display_view_cb (ETaskShellContent *task_shell_content,
                                    GalView *gal_view)
{
    ETaskTable *task_table;

    if (!GAL_IS_VIEW_ETABLE (gal_view))
        return;

    task_table = e_task_shell_content_get_task_table (task_shell_content);

    gal_view_etable_attach_table (
        GAL_VIEW_ETABLE (gal_view), E_TABLE (task_table));
}

static void
task_shell_content_table_foreach_cb (gint model_row,
                                     gpointer user_data)
{
    ECalModelComponent *comp_data;
    icalcomponent *clone;
    icalcomponent *vcal;
    gchar *string;

    struct {
        ECalModel *model;
        GSList *list;
    } *foreach_data = user_data;

    comp_data = e_cal_model_get_component_at (
        foreach_data->model, model_row);

    vcal = e_cal_util_new_top_level ();
    clone = icalcomponent_new_clone (comp_data->icalcomp);
    e_cal_util_add_timezones_from_component (vcal, comp_data->icalcomp);
    icalcomponent_add_component (vcal, clone);

    /* String is owned by libical; do not free. */
    string = icalcomponent_as_ical_string (vcal);
    if (string != NULL) {
        ESource *source;
        const gchar *source_uid;

        source = e_client_get_source (E_CLIENT (comp_data->client));
        source_uid = e_source_get_uid (source);

        foreach_data->list = g_slist_prepend (
            foreach_data->list,
            g_strdup_printf ("%s\n%s", source_uid, string));
    }

    icalcomponent_free (vcal);
}

static void
task_shell_content_table_drag_data_get_cb (ETaskShellContent *task_shell_content,
                                           gint row,
                                           gint col,
                                           GdkDragContext *context,
                                           GtkSelectionData *selection_data,
                                           guint info,
                                           guint time)
{
    ETaskTable *task_table;
    GdkAtom target;

    struct {
        ECalModel *model;
        GSList *list;
    } foreach_data;

    /* Sanity check the selection target. */
    target = gtk_selection_data_get_target (selection_data);
    if (!e_targets_include_calendar (&target, 1))
        return;

    task_table = e_task_shell_content_get_task_table (task_shell_content);

    foreach_data.model = e_task_table_get_model (task_table);
    foreach_data.list = NULL;

    e_table_selected_row_foreach (
        E_TABLE (task_table),
        task_shell_content_table_foreach_cb,
        &foreach_data);

    if (foreach_data.list != NULL) {
        cal_comp_selection_set_string_list (
            selection_data, foreach_data.list);
        g_slist_foreach (foreach_data.list, (GFunc) g_free, NULL);
        g_slist_free (foreach_data.list);
    }
}

static void
task_shell_content_table_drag_data_delete_cb (ETaskShellContent *task_shell_content,
                                              gint row,
                                              gint col,
                                              GdkDragContext *context)
{
    /* Moved components are deleted from source immediately when moved,
     * because some of them can be part of destination source, and we
     * don't want to delete not-moved tasks.  There is no such information
     * which event has been moved and which not, so skip this method. */
}

static void
task_shell_content_cursor_change_cb (ETaskShellContent *task_shell_content,
                                     gint row,
                                     ETable *table)
{
    ECalComponentPreview *task_preview;
    ECalModel *task_model;
    ECalModelComponent *comp_data;
    EPreviewPane *preview_pane;
    EWebView *web_view;
    const gchar *uid;

    task_model = e_task_shell_content_get_task_model (task_shell_content);
    preview_pane = e_task_shell_content_get_preview_pane (task_shell_content);

    web_view = e_preview_pane_get_web_view (preview_pane);
    task_preview = E_CAL_COMPONENT_PREVIEW (web_view);

    if (e_table_selected_count (table) != 1) {
        if (task_shell_content->priv->preview_visible)
            e_cal_component_preview_clear (task_preview);
        return;
    }

    row = e_table_get_cursor_row (table);
    comp_data = e_cal_model_get_component_at (task_model, row);

    if (task_shell_content->priv->preview_visible) {
        ECalComponent *comp;

        comp = e_cal_component_new_from_icalcomponent (
                icalcomponent_new_clone (comp_data->icalcomp));

        e_cal_component_preview_display (
            task_preview, comp_data->client, comp,
            e_cal_model_get_timezone (task_model),
            e_cal_model_get_use_24_hour_format (task_model));

        g_object_unref (comp);
    }

    uid = icalcomponent_get_uid (comp_data->icalcomp);
    g_free (task_shell_content->priv->current_uid);
    task_shell_content->priv->current_uid = g_strdup (uid);
}

static void
task_shell_content_selection_change_cb (ETaskShellContent *task_shell_content,
                                        ETable *table)
{
    ECalComponentPreview *task_preview;
    EPreviewPane *preview_pane;
    EWebView *web_view;

    preview_pane = e_task_shell_content_get_preview_pane (task_shell_content);

    web_view = e_preview_pane_get_web_view (preview_pane);
    task_preview = E_CAL_COMPONENT_PREVIEW (web_view);

    if (e_table_selected_count (table) != 1)
        e_cal_component_preview_clear (task_preview);
}

static void
task_shell_content_model_row_changed_cb (ETaskShellContent *task_shell_content,
                                         gint row,
                                         ETableModel *model)
{
    ECalModelComponent *comp_data;
    ETaskTable *task_table;
    const gchar *current_uid;
    const gchar *uid;

    current_uid = task_shell_content->priv->current_uid;
    if (current_uid == NULL)
        return;

    comp_data = e_cal_model_get_component_at (E_CAL_MODEL (model), row);
    if (comp_data == NULL)
        return;

    uid = icalcomponent_get_uid (comp_data->icalcomp);
    if (g_strcmp0 (uid, current_uid) != 0)
        return;

    task_table = e_task_shell_content_get_task_table (task_shell_content);

    task_shell_content_cursor_change_cb (
        task_shell_content, 0, E_TABLE (task_table));
}

static void
task_shell_content_restore_state_cb (EShellWindow *shell_window,
                                     EShellView *shell_view,
                                     EShellContent *shell_content)
{
    ETaskShellContentPrivate *priv;
    GSettings *settings;

    priv = E_TASK_SHELL_CONTENT_GET_PRIVATE (shell_content);

    /* Bind GObject properties to settings keys. */

    settings = g_settings_new ("org.gnome.evolution.calendar");

    g_settings_bind (
        settings, "task-hpane-position",
        priv->paned, "hposition",
        G_SETTINGS_BIND_DEFAULT);

    g_settings_bind (
        settings, "task-vpane-position",
        priv->paned, "vposition",
        G_SETTINGS_BIND_DEFAULT);

    g_object_unref (G_OBJECT (settings));
}

static GtkOrientation
task_shell_content_get_orientation (ETaskShellContent *task_shell_content)
{
    return task_shell_content->priv->orientation;
}

static void
task_shell_content_set_orientation (ETaskShellContent *task_shell_content,
                                    GtkOrientation orientation)
{
    if (task_shell_content->priv->orientation == orientation)
        return;

    task_shell_content->priv->orientation = orientation;

    g_object_notify (G_OBJECT (task_shell_content), "orientation");
}

static void
task_shell_content_set_property (GObject *object,
                                 guint property_id,
                                 const GValue *value,
                                 GParamSpec *pspec)
{
    switch (property_id) {
        case PROP_ORIENTATION:
            task_shell_content_set_orientation (
                E_TASK_SHELL_CONTENT (object),
                g_value_get_enum (value));
            return;

        case PROP_PREVIEW_VISIBLE:
            e_task_shell_content_set_preview_visible (
                E_TASK_SHELL_CONTENT (object),
                g_value_get_boolean (value));
            return;
    }

    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}

static void
task_shell_content_get_property (GObject *object,
                                 guint property_id,
                                 GValue *value,
                                 GParamSpec *pspec)
{
    switch (property_id) {
        case PROP_MODEL:
            g_value_set_object (
                value,
                e_task_shell_content_get_task_model (
                E_TASK_SHELL_CONTENT (object)));
            return;

        case PROP_ORIENTATION:
            g_value_set_enum (
                value,
                task_shell_content_get_orientation (
                E_TASK_SHELL_CONTENT (object)));
            return;

        case PROP_PREVIEW_VISIBLE:
            g_value_set_boolean (
                value,
                e_task_shell_content_get_preview_visible (
                E_TASK_SHELL_CONTENT (object)));
            return;
    }

    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}

static void
task_shell_content_dispose (GObject *object)
{
    ETaskShellContentPrivate *priv;

    priv = E_TASK_SHELL_CONTENT_GET_PRIVATE (object);

    if (priv->paned != NULL) {
        g_object_unref (priv->paned);
        priv->paned = NULL;
    }

    if (priv->task_table != NULL) {
        g_object_unref (priv->task_table);
        priv->task_table = NULL;
    }

    if (priv->preview_pane != NULL) {
        g_object_unref (priv->preview_pane);
        priv->preview_pane = NULL;
    }

    if (priv->task_model != NULL) {
        g_object_unref (priv->task_model);
        priv->task_model = NULL;
    }

    if (priv->view_instance != NULL) {
        g_object_unref (priv->view_instance);
        priv->view_instance = NULL;
    }

    /* Chain up to parent's dispose() method. */
    G_OBJECT_CLASS (e_task_shell_content_parent_class)->dispose (object);
}

static void
task_shell_content_finalize (GObject *object)
{
    ETaskShellContentPrivate *priv;

    priv = E_TASK_SHELL_CONTENT_GET_PRIVATE (object);

    g_free (priv->current_uid);

    /* Chain up to parent's finalize() method. */
    G_OBJECT_CLASS (e_task_shell_content_parent_class)->finalize (object);
}

static void
task_shell_content_constructed (GObject *object)
{
    ETaskShellContentPrivate *priv;
    EShell *shell;
    EShellView *shell_view;
    EShellWindow *shell_window;
    EShellContent *shell_content;
    EShellTaskbar *shell_taskbar;
    ESourceRegistry *registry;
    GalViewInstance *view_instance;
    GtkTargetList *target_list;
    GtkTargetEntry *targets;
    GtkWidget *container;
    GtkWidget *widget;
    gint n_targets;

    priv = E_TASK_SHELL_CONTENT_GET_PRIVATE (object);

    /* Chain up to parent's constructed() method. */
    G_OBJECT_CLASS (e_task_shell_content_parent_class)->constructed (object);

    shell_content = E_SHELL_CONTENT (object);
    shell_view = e_shell_content_get_shell_view (shell_content);
    shell_taskbar = e_shell_view_get_shell_taskbar (shell_view);
    shell_window = e_shell_view_get_shell_window (shell_view);
    shell = e_shell_window_get_shell (shell_window);

    registry = e_shell_get_registry (shell);
    priv->task_model = e_cal_model_tasks_new (registry);

    /* Build content widgets. */

    container = GTK_WIDGET (object);

    widget = e_paned_new (GTK_ORIENTATION_VERTICAL);
    gtk_container_add (GTK_CONTAINER (container), widget);
    priv->paned = g_object_ref (widget);
    gtk_widget_show (widget);

    g_object_bind_property (
        object, "orientation",
        widget, "orientation",
        G_BINDING_SYNC_CREATE);

    container = priv->paned;

    widget = gtk_scrolled_window_new (NULL, NULL);
    gtk_scrolled_window_set_policy (
        GTK_SCROLLED_WINDOW (widget),
        GTK_POLICY_AUTOMATIC, GTK_POLICY_AUTOMATIC);
    gtk_scrolled_window_set_shadow_type (
        GTK_SCROLLED_WINDOW (widget), GTK_SHADOW_IN);
    gtk_paned_pack1 (GTK_PANED (container), widget, TRUE, FALSE);
    gtk_widget_show (widget);

    container = widget;

    widget = e_task_table_new (shell_view, priv->task_model);
    gtk_container_add (GTK_CONTAINER (container), widget);
    priv->task_table = g_object_ref (widget);
    gtk_widget_show (widget);

    container = priv->paned;

    widget = e_cal_component_preview_new ();
    gtk_widget_show (widget);

    g_signal_connect_swapped (
        widget, "status-message",
        G_CALLBACK (e_shell_taskbar_set_message),
        shell_taskbar);

    widget = e_preview_pane_new (E_WEB_VIEW (widget));
    gtk_paned_pack2 (GTK_PANED (container), widget, FALSE, FALSE);
    priv->preview_pane = g_object_ref (widget);
    gtk_widget_show (widget);

    g_object_bind_property (
        object, "preview-visible",
        widget, "visible",
        G_BINDING_SYNC_CREATE);

    /* Configure the task table. */

    e_table_set_state (
        E_TABLE (priv->task_table), E_TASK_TABLE_DEFAULT_STATE);

    target_list = gtk_target_list_new (NULL, 0);
    e_target_list_add_calendar_targets (target_list, 0);
    targets = gtk_target_table_new_from_list (target_list, &n_targets);

    e_table_drag_source_set (
        E_TABLE (priv->task_table),
        GDK_BUTTON1_MASK, targets, n_targets,
        GDK_ACTION_MOVE | GDK_ACTION_COPY | GDK_ACTION_ASK);

    gtk_target_table_free (targets, n_targets);
    gtk_target_list_unref (target_list);

    g_signal_connect_swapped (
        priv->task_table, "table-drag-data-get",
        G_CALLBACK (task_shell_content_table_drag_data_get_cb),
        object);

    g_signal_connect_swapped (
        priv->task_table, "table-drag-data-delete",
        G_CALLBACK (task_shell_content_table_drag_data_delete_cb),
        object);

    g_signal_connect_swapped (
        priv->task_table, "cursor-change",
        G_CALLBACK (task_shell_content_cursor_change_cb),
        object);

    g_signal_connect_swapped (
        priv->task_table, "selection-change",
        G_CALLBACK (task_shell_content_selection_change_cb),
        object);

    g_signal_connect_swapped (
        priv->task_model, "model-row-changed",
        G_CALLBACK (task_shell_content_model_row_changed_cb),
        object);

    /* Load the view instance. */

    view_instance = e_shell_view_new_view_instance (shell_view, NULL);
    g_signal_connect_swapped (
        view_instance, "display-view",
        G_CALLBACK (task_shell_content_display_view_cb),
        object);
    priv->view_instance = view_instance;

    /* Do this last so e_task_shell_content_get_view_instance() returns
     * the correct instance in GalViewInstance::loaded signal handlers. */
    gal_view_instance_load (view_instance);

    /* Restore pane positions from the last session once
     * the shell view is fully initialized and visible. */
    g_signal_connect (
        shell_window, "shell-view-created::tasks",
        G_CALLBACK (task_shell_content_restore_state_cb),
        shell_content);
}

static guint32
task_shell_content_check_state (EShellContent *shell_content)
{
    ETaskShellContent *task_shell_content;
    ETaskTable *task_table;
    GSList *list, *iter;
    gboolean assignable = TRUE;
    gboolean editable = TRUE;
    gboolean has_url = FALSE;
    gint n_selected;
    gint n_complete = 0;
    gint n_incomplete = 0;
    guint32 state = 0;

    task_shell_content = E_TASK_SHELL_CONTENT (shell_content);
    task_table = e_task_shell_content_get_task_table (task_shell_content);

    n_selected = e_table_selected_count (E_TABLE (task_table));

    list = e_task_table_get_selected (task_table);
    for (iter = list; iter != NULL; iter = iter->next) {
        ECalModelComponent *comp_data = iter->data;
        icalproperty *prop;
        const gchar *cap;
        gboolean read_only;

        read_only = e_client_is_readonly (E_CLIENT (comp_data->client));
        editable &= !read_only;

        cap = CAL_STATIC_CAPABILITY_NO_TASK_ASSIGNMENT;
        if (e_client_check_capability (E_CLIENT (comp_data->client), cap))
            assignable = FALSE;

        cap = CAL_STATIC_CAPABILITY_NO_CONV_TO_ASSIGN_TASK;
        if (e_client_check_capability (E_CLIENT (comp_data->client), cap))
            assignable = FALSE;

        prop = icalcomponent_get_first_property (
            comp_data->icalcomp, ICAL_URL_PROPERTY);
        has_url |= (prop != NULL);

        prop = icalcomponent_get_first_property (
            comp_data->icalcomp, ICAL_COMPLETED_PROPERTY);
        if (prop != NULL)
            n_complete++;
        else
            n_incomplete++;
    }
    g_slist_free (list);

    if (n_selected == 1)
        state |= E_TASK_SHELL_CONTENT_SELECTION_SINGLE;
    if (n_selected > 1)
        state |= E_TASK_SHELL_CONTENT_SELECTION_MULTIPLE;
    if (assignable)
        state |= E_TASK_SHELL_CONTENT_SELECTION_CAN_ASSIGN;
    if (editable)
        state |= E_TASK_SHELL_CONTENT_SELECTION_CAN_EDIT;
    if (n_complete > 0)
        state |= E_TASK_SHELL_CONTENT_SELECTION_HAS_COMPLETE;
    if (n_incomplete > 0)
        state |= E_TASK_SHELL_CONTENT_SELECTION_HAS_INCOMPLETE;
    if (has_url)
        state |= E_TASK_SHELL_CONTENT_SELECTION_HAS_URL;

    return state;
}

static void
task_shell_content_focus_search_results (EShellContent *shell_content)
{
    ETaskShellContentPrivate *priv;

    priv = E_TASK_SHELL_CONTENT_GET_PRIVATE (shell_content);

    gtk_widget_grab_focus (priv->task_table);
}

static void
e_task_shell_content_class_init (ETaskShellContentClass *class)
{
    GObjectClass *object_class;
    EShellContentClass *shell_content_class;

    g_type_class_add_private (class, sizeof (ETaskShellContentPrivate));

    object_class = G_OBJECT_CLASS (class);
    object_class->set_property = task_shell_content_set_property;
    object_class->get_property = task_shell_content_get_property;
    object_class->dispose = task_shell_content_dispose;
    object_class->finalize = task_shell_content_finalize;
    object_class->constructed = task_shell_content_constructed;

    shell_content_class = E_SHELL_CONTENT_CLASS (class);
    shell_content_class->check_state = task_shell_content_check_state;
    shell_content_class->focus_search_results =
        task_shell_content_focus_search_results;

    g_object_class_install_property (
        object_class,
        PROP_MODEL,
        g_param_spec_object (
            "model",
            "Model",
            "The task table model",
            E_TYPE_CAL_MODEL,
            G_PARAM_READABLE));

    g_object_class_install_property (
        object_class,
        PROP_PREVIEW_VISIBLE,
        g_param_spec_boolean (
            "preview-visible",
            "Preview is Visible",
            "Whether the preview pane is visible",
            TRUE,
            G_PARAM_READWRITE |
            G_PARAM_CONSTRUCT));

    g_object_class_override_property (
        object_class, PROP_ORIENTATION, "orientation");
}

static void
e_task_shell_content_class_finalize (ETaskShellContentClass *class)
{
}

static void
e_task_shell_content_init (ETaskShellContent *task_shell_content)
{
    task_shell_content->priv =
        E_TASK_SHELL_CONTENT_GET_PRIVATE (task_shell_content);

    /* Postpone widget construction until we have a shell view. */
}

void
e_task_shell_content_type_register (GTypeModule *type_module)
{
    /* XXX G_DEFINE_DYNAMIC_TYPE declares a static type registration
     *     function, so we have to wrap it with a public function in
     *     order to register types from a separate compilation unit. */
    e_task_shell_content_register_type (type_module);
}

GtkWidget *
e_task_shell_content_new (EShellView *shell_view)
{
    g_return_val_if_fail (E_IS_SHELL_VIEW (shell_view), NULL);

    return g_object_new (
        E_TYPE_TASK_SHELL_CONTENT,
        "shell-view", shell_view, NULL);
}

ECalModel *
e_task_shell_content_get_task_model (ETaskShellContent *task_shell_content)
{
    g_return_val_if_fail (
        E_IS_TASK_SHELL_CONTENT (task_shell_content), NULL);

    return task_shell_content->priv->task_model;
}

ETaskTable *
e_task_shell_content_get_task_table (ETaskShellContent *task_shell_content)
{
    g_return_val_if_fail (
        E_IS_TASK_SHELL_CONTENT (task_shell_content), NULL);

    return E_TASK_TABLE (task_shell_content->priv->task_table);
}

EPreviewPane *
e_task_shell_content_get_preview_pane (ETaskShellContent *task_shell_content)
{
    g_return_val_if_fail (
        E_IS_TASK_SHELL_CONTENT (task_shell_content), NULL);

    return E_PREVIEW_PANE (task_shell_content->priv->preview_pane);
}

gboolean
e_task_shell_content_get_preview_visible (ETaskShellContent *task_shell_content)
{
    g_return_val_if_fail (
        E_IS_TASK_SHELL_CONTENT (task_shell_content), FALSE);

    return task_shell_content->priv->preview_visible;
}

void
e_task_shell_content_set_preview_visible (ETaskShellContent *task_shell_content,
                                          gboolean preview_visible)
{
    g_return_if_fail (E_IS_TASK_SHELL_CONTENT (task_shell_content));

    if ((task_shell_content->priv->preview_visible ? 1 : 0) == (preview_visible ? 1 : 0))
        return;

    task_shell_content->priv->preview_visible = preview_visible;

    if (preview_visible && task_shell_content->priv->preview_pane) {
        task_shell_content_cursor_change_cb (
            task_shell_content, 0,
            E_TABLE (task_shell_content->priv->task_table));
    }

    g_object_notify (G_OBJECT (task_shell_content), "preview-visible");
}

EShellSearchbar *
e_task_shell_content_get_searchbar (ETaskShellContent *task_shell_content)
{
    EShellView *shell_view;
    EShellContent *shell_content;
    GtkWidget *widget;

    g_return_val_if_fail (
        E_IS_TASK_SHELL_CONTENT (task_shell_content), NULL);

    shell_content = E_SHELL_CONTENT (task_shell_content);
    shell_view = e_shell_content_get_shell_view (shell_content);
    widget = e_shell_view_get_searchbar (shell_view);

    return E_SHELL_SEARCHBAR (widget);
}

GalViewInstance *
e_task_shell_content_get_view_instance (ETaskShellContent *task_shell_content)
{
    g_return_val_if_fail (
        E_IS_TASK_SHELL_CONTENT (task_shell_content), NULL);

    return task_shell_content->priv->view_instance;
}