path: root/shell/e-shell-switcher.c

/*
 * e-shell-switcher.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)
 *
 */

/**
 * SECTION: e-shell-switcher
 * @short_description: buttons for switching views
 * @include: shell/e-shell-switcher.h
 **/

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

#include "e-shell-switcher.h"

#include <glib/gi18n.h>
#include <e-util/e-extensible.h>

#define H_PADDING 6
#define V_PADDING 6

struct _EShellSwitcherPrivate {
    GList *proxies;
    gboolean style_set;
    GtkToolbarStyle style;
    GtkSettings *settings;
    gulong settings_handler_id;
    gboolean toolbar_visible;
};

enum {
    PROP_0,
    PROP_TOOLBAR_STYLE,
    PROP_TOOLBAR_VISIBLE
};

enum {
    STYLE_CHANGED,
    LAST_SIGNAL
};

static guint signals[LAST_SIGNAL];

/* Forward Declarations */
static void shell_switcher_tool_shell_iface_init (GtkToolShellIface *iface);

G_DEFINE_TYPE_WITH_CODE (
    EShellSwitcher,
    e_shell_switcher,
    GTK_TYPE_BIN,
    G_IMPLEMENT_INTERFACE (
        E_TYPE_EXTENSIBLE, NULL)
    G_IMPLEMENT_INTERFACE (
        GTK_TYPE_TOOL_SHELL,
        shell_switcher_tool_shell_iface_init))

static gint
shell_switcher_layout_actions (EShellSwitcher *switcher)
{
    GtkAllocation allocation;
    gint num_btns = g_list_length (switcher->priv->proxies), btns_per_row;
    GList **rows, *p;
    gboolean icons_only;
    gint row_number;
    gint max_width = 0;
    gint max_height = 0;
    gint row_last;
    gint x, y;
    gint i;

    gtk_widget_get_allocation (GTK_WIDGET (switcher), &allocation);

    y = allocation.y + allocation.height;

    if (num_btns == 0)
        return allocation.height;

    icons_only = (switcher->priv->style == GTK_TOOLBAR_ICONS);

    /* Figure out the max width and height. */
    for (p = switcher->priv->proxies; p != NULL; p = p->next) {
        GtkWidget *widget = p->data;
        GtkRequisition requisition;

        gtk_widget_get_preferred_size (widget, &requisition, NULL);
        max_height = MAX (max_height, requisition.height);
        max_width = MAX (max_width, requisition.width);
    }

    /* Figure out how many rows and columns we'll use. */
    btns_per_row = MAX (1, allocation.width / (max_width + H_PADDING));
    if (!icons_only) {
        /* If using text buttons, we want to try to have a
         * completely filled-in grid, but if we can't, we want
         * the odd row to have just a single button. */
        while (btns_per_row > 0 && num_btns % btns_per_row > 1)
            btns_per_row--;
    }

    /* Assign buttons to rows. */
    rows = g_new0 (GList *, num_btns / btns_per_row + 1);

    if (!icons_only && num_btns % btns_per_row != 0) {
        rows[0] = g_list_append (rows[0], switcher->priv->proxies->data);

        p = switcher->priv->proxies->next;
        row_number = p ? 1 : 0;
    } else {
        p = switcher->priv->proxies;
        row_number = 0;
    }

    for (; p != NULL; p = p->next) {
        GtkWidget *widget = p->data;

        if (g_list_length (rows[row_number]) == btns_per_row)
            row_number++;

        rows[row_number] = g_list_append (rows[row_number], widget);
    }

    row_last = row_number;

    /* Layout the buttons. */
    for (i = row_last; i >= 0; i--) {
        gint len, extra_width;

        x = H_PADDING + allocation.x;
        y -= max_height;
        len = g_list_length (rows[i]);
        if (!icons_only)
            extra_width =
                (allocation.width - (len * max_width) -
                (len * H_PADDING)) / len;
        else
            extra_width = 0;
        for (p = rows[i]; p != NULL; p = p->next) {
            GtkAllocation child_allocation;

            child_allocation.x = x;
            child_allocation.y = y;
            child_allocation.width = max_width + extra_width;
            child_allocation.height = max_height;

            gtk_widget_size_allocate (GTK_WIDGET (p->data), &child_allocation);

            x += child_allocation.width + H_PADDING;
        }

        y -= V_PADDING;
    }

    for (i = 0; i <= row_last; i++)
        g_list_free (rows[i]);
    g_free (rows);

    return y - allocation.y;
}

static void
shell_switcher_toolbar_style_changed_cb (EShellSwitcher *switcher)
{
    if (!switcher->priv->style_set) {
        switcher->priv->style_set = TRUE;
        e_shell_switcher_unset_style (switcher);
    }
}

static void
shell_switcher_set_property (GObject *object,
                             guint property_id,
                             const GValue *value,
                             GParamSpec *pspec)
{
    switch (property_id) {
        case PROP_TOOLBAR_STYLE:
            e_shell_switcher_set_style (
                E_SHELL_SWITCHER (object),
                g_value_get_enum (value));
            return;

        case PROP_TOOLBAR_VISIBLE:
            e_shell_switcher_set_visible (
                E_SHELL_SWITCHER (object),
                g_value_get_boolean (value));
            return;
    }

    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}

static void
shell_switcher_get_property (GObject *object,
                             guint property_id,
                             GValue *value,
                             GParamSpec *pspec)
{
    switch (property_id) {
        case PROP_TOOLBAR_STYLE:
            g_value_set_enum (
                value, e_shell_switcher_get_style (
                E_SHELL_SWITCHER (object)));
            return;

        case PROP_TOOLBAR_VISIBLE:
            g_value_set_boolean (
                value, e_shell_switcher_get_visible (
                E_SHELL_SWITCHER (object)));
            return;
    }

    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}

static void
shell_switcher_dispose (GObject *object)
{
    EShellSwitcherPrivate *priv;

    priv = E_SHELL_SWITCHER (object)->priv;

    while (priv->proxies != NULL) {
        GtkWidget *widget = priv->proxies->data;
        gtk_container_remove (GTK_CONTAINER (object), widget);
    }

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

static void
shell_switcher_get_preferred_width (GtkWidget *widget,
                                    gint      *minimum,
                                    gint      *natural)
{
    EShellSwitcherPrivate *priv;
    GtkWidget *child;
    GList *iter;

    priv = E_SHELL_SWITCHER (widget)->priv;

    *minimum = *natural = 0;

    child = gtk_bin_get_child (GTK_BIN (widget));
    if (child != NULL)
        gtk_widget_get_preferred_width (child, minimum, natural);

    if (!priv->toolbar_visible)
        return;

    for (iter = priv->proxies; iter != NULL; iter = iter->next) {
        GtkWidget *widget_proxy = iter->data;
        gint child_min, child_nat;

        gtk_widget_get_preferred_width (
            widget_proxy, &child_min, &child_nat);

        child_min += H_PADDING;
        child_nat += H_PADDING;

        *minimum = MAX (*minimum, child_min);
        *natural = MAX (*natural, child_nat);
    }
}

static void
shell_switcher_get_preferred_height (GtkWidget *widget,
                                     gint      *minimum,
                                     gint      *natural)
{
    EShellSwitcherPrivate *priv;
    GtkWidget *child;
    GList *iter;

    priv = E_SHELL_SWITCHER (widget)->priv;

    *minimum = *natural = 0;

    child = gtk_bin_get_child (GTK_BIN (widget));
    if (child != NULL)
        gtk_widget_get_preferred_height (child, minimum, natural);

    if (!priv->toolbar_visible)
        return;

    for (iter = priv->proxies; iter != NULL; iter = iter->next) {
        GtkWidget *widget = iter->data;
        gint child_min, child_nat;

        gtk_widget_get_preferred_height (
            widget, &child_min, &child_nat);

        child_min += V_PADDING;
        child_nat += V_PADDING;

        *minimum += child_min;
        *natural += child_nat;
    }
}

static void
shell_switcher_size_allocate (GtkWidget *widget,
                              GtkAllocation *allocation)
{
    EShellSwitcher *switcher;
    GtkAllocation child_allocation;
    GtkWidget *child;
    gint height;

    switcher = E_SHELL_SWITCHER (widget);

    gtk_widget_set_allocation (widget, allocation);

    if (switcher->priv->toolbar_visible)
        height = shell_switcher_layout_actions (switcher);
    else
        height = allocation->height;

    child_allocation.x = allocation->x;
    child_allocation.y = allocation->y;
    child_allocation.width = allocation->width;
    child_allocation.height = height;

    child = gtk_bin_get_child (GTK_BIN (widget));
    if (child != NULL)
        gtk_widget_size_allocate (child, &child_allocation);
}

static void
shell_switcher_screen_changed (GtkWidget *widget,
                               GdkScreen *previous_screen)
{
    EShellSwitcherPrivate *priv;
    GtkSettings *settings;

    priv = E_SHELL_SWITCHER (widget)->priv;

    if (gtk_widget_has_screen (widget))
        settings = gtk_widget_get_settings (widget);
    else
        settings = NULL;

    if (settings == priv->settings)
        return;

    if (priv->settings != NULL) {
        g_signal_handler_disconnect (
            priv->settings, priv->settings_handler_id);
        g_object_unref (priv->settings);
    }

    if (settings != NULL) {
        priv->settings = g_object_ref (settings);
        priv->settings_handler_id = g_signal_connect_swapped (
            settings, "notify::gtk-toolbar-style",
            G_CALLBACK (shell_switcher_toolbar_style_changed_cb),
            widget);
    } else
        priv->settings = NULL;

    shell_switcher_toolbar_style_changed_cb (E_SHELL_SWITCHER (widget));
}

static void
shell_switcher_remove (GtkContainer *container,
                       GtkWidget *widget)
{
    EShellSwitcherPrivate *priv;
    GList *link;

    priv = E_SHELL_SWITCHER (container)->priv;

    /* Look in the internal widgets first. */

    link = g_list_find (priv->proxies, widget);
    if (link != NULL) {
        GtkWidget *widget = link->data;

        gtk_widget_unparent (widget);
        priv->proxies = g_list_delete_link (priv->proxies, link);
        gtk_widget_queue_resize (GTK_WIDGET (container));
        return;
    }

    /* Chain up to parent's remove() method. */
    GTK_CONTAINER_CLASS (e_shell_switcher_parent_class)->remove (
        container, widget);
}

static void
shell_switcher_forall (GtkContainer *container,
                       gboolean include_internals,
                       GtkCallback callback,
                       gpointer callback_data)
{
    EShellSwitcherPrivate *priv;

    priv = E_SHELL_SWITCHER (container)->priv;

    if (include_internals)
        g_list_foreach (
            priv->proxies, (GFunc) callback, callback_data);

    /* Chain up to parent's forall() method. */
    GTK_CONTAINER_CLASS (e_shell_switcher_parent_class)->forall (
        container, include_internals, callback, callback_data);
}

static void
shell_switcher_style_changed (EShellSwitcher *switcher,
                              GtkToolbarStyle style)
{
    if (switcher->priv->style == style)
        return;

    switcher->priv->style = style;

    g_list_foreach (
        switcher->priv->proxies,
        (GFunc) gtk_tool_item_toolbar_reconfigured, NULL);

    gtk_widget_queue_resize (GTK_WIDGET (switcher));
    g_object_notify (G_OBJECT (switcher), "toolbar-style");
}

static GtkIconSize
shell_switcher_get_icon_size (GtkToolShell *shell)
{
    return GTK_ICON_SIZE_LARGE_TOOLBAR;
}

static GtkOrientation
shell_switcher_get_orientation (GtkToolShell *shell)
{
    return GTK_ORIENTATION_HORIZONTAL;
}

static GtkToolbarStyle
shell_switcher_get_style (GtkToolShell *shell)
{
    return e_shell_switcher_get_style (E_SHELL_SWITCHER (shell));
}

static GtkReliefStyle
shell_switcher_get_relief_style (GtkToolShell *shell)
{
    return GTK_RELIEF_NORMAL;
}

static gfloat
shell_switcher_get_text_alignment (GtkToolShell *shell)
{
    return 0.0;
}

static void
e_shell_switcher_class_init (EShellSwitcherClass *class)
{
    GObjectClass *object_class;
    GtkWidgetClass *widget_class;
    GtkContainerClass *container_class;

    g_type_class_add_private (class, sizeof (EShellSwitcherPrivate));

    object_class = G_OBJECT_CLASS (class);
    object_class->set_property = shell_switcher_set_property;
    object_class->get_property = shell_switcher_get_property;
    object_class->dispose = shell_switcher_dispose;

    widget_class = GTK_WIDGET_CLASS (class);
    widget_class->get_preferred_width = shell_switcher_get_preferred_width;
    widget_class->get_preferred_height = shell_switcher_get_preferred_height;
    widget_class->size_allocate = shell_switcher_size_allocate;
    widget_class->screen_changed = shell_switcher_screen_changed;

    container_class = GTK_CONTAINER_CLASS (class);
    container_class->remove = shell_switcher_remove;
    container_class->forall = shell_switcher_forall;

    class->style_changed = shell_switcher_style_changed;

    /**
     * EShellSwitcher:toolbar-style
     *
     * The switcher's toolbar style.
     **/
    g_object_class_install_property (
        object_class,
        PROP_TOOLBAR_STYLE,
        g_param_spec_enum (
            "toolbar-style",
            "Toolbar Style",
            "The switcher's toolbar style",
            GTK_TYPE_TOOLBAR_STYLE,
            E_SHELL_SWITCHER_DEFAULT_TOOLBAR_STYLE,
            G_PARAM_READWRITE |
            G_PARAM_CONSTRUCT));

    /**
     * EShellSwitcher:toolbar-visible
     *
     * Whether the switcher is visible.
     **/
    g_object_class_install_property (
        object_class,
        PROP_TOOLBAR_VISIBLE,
        g_param_spec_boolean (
            "toolbar-visible",
            "Toolbar Visible",
            "Whether the switcher is visible",
            TRUE,
            G_PARAM_READWRITE |
            G_PARAM_CONSTRUCT));

    /**
     * EShellSwitcher::style-changed
     * @switcher: the #EShellSwitcher which emitted the signal
     * @style: the new #GtkToolbarStyle of the switcher
     *
     * Emitted when the style of the switcher changes.
     **/
    signals[STYLE_CHANGED] = g_signal_new (
        "style-changed",
        G_OBJECT_CLASS_TYPE (class),
        G_SIGNAL_RUN_FIRST,
        G_STRUCT_OFFSET (EShellSwitcherClass, style_changed),
        NULL, NULL,
        g_cclosure_marshal_VOID__ENUM,
        G_TYPE_NONE, 1,
        GTK_TYPE_TOOLBAR_STYLE);
}

static void
e_shell_switcher_init (EShellSwitcher *switcher)
{
    switcher->priv = G_TYPE_INSTANCE_GET_PRIVATE (
        switcher, E_TYPE_SHELL_SWITCHER, EShellSwitcherPrivate);

    gtk_widget_set_has_window (GTK_WIDGET (switcher), FALSE);

    e_extensible_load_extensions (E_EXTENSIBLE (switcher));
}

static void
shell_switcher_tool_shell_iface_init (GtkToolShellIface *iface)
{
    iface->get_icon_size = shell_switcher_get_icon_size;
    iface->get_orientation = shell_switcher_get_orientation;
    iface->get_style = shell_switcher_get_style;
    iface->get_relief_style = shell_switcher_get_relief_style;
    iface->get_text_alignment = shell_switcher_get_text_alignment;
}

/**
 * e_shell_switcher_new:
 *
 * Creates a new #EShellSwitcher instance.
 *
 * Returns: a new #EShellSwitcher instance
 **/
GtkWidget *
e_shell_switcher_new (void)
{
    return g_object_new (E_TYPE_SHELL_SWITCHER, NULL);
}

/*
 * gtk+ doesn't give us what we want - a middle click,
 * option on toolbar items, so we have to get it by force.
 */
static GtkButton *
tool_item_get_button (GtkWidget *widget)
{
    GtkWidget *child;

    g_return_val_if_fail (GTK_IS_TOOL_ITEM (widget), NULL);

    child = gtk_bin_get_child (GTK_BIN (widget));
    if (child != NULL && GTK_IS_BUTTON (child))
        return GTK_BUTTON (child);
    else
        return NULL;
}

static gboolean
tool_item_button_cb (GtkWidget      *internal_widget,
             GdkEventButton *event,
             GtkAction      *action)
{
    g_return_val_if_fail (GTK_IS_ACTION (action), FALSE);

    if (event->button == 2) {
        gtk_action_activate (action);
        return TRUE;
    }
    return FALSE;
}

/**
 * e_shell_switcher_add_action:
 * @switcher: an #EShellSwitcher
 * @switch_action: a #GtkAction
 * @new_window_action: a #GtkAction
 *
 * Adds a button to @switcher that proxies for @switcher_action.
 * Switcher buttons appear in the order they were added. A middle
 * click opens a new window of this type.
 *
 * #EShellWindow adds switcher actions in the order given by the
 * <structfield>sort_order</structfield> field in #EShellBackendClass.
 **/
void
e_shell_switcher_add_action (EShellSwitcher *switcher,
                 GtkAction      *switch_action,
                 GtkAction      *new_window_action)
{
    GtkWidget *widget;
    GtkButton *button;

    g_return_if_fail (E_IS_SHELL_SWITCHER (switcher));
    g_return_if_fail (GTK_IS_ACTION (switch_action));
    g_return_if_fail (GTK_IS_ACTION (new_window_action));

    g_object_ref (switch_action);
    widget = gtk_action_create_tool_item (switch_action);
    gtk_tool_item_set_is_important (GTK_TOOL_ITEM (widget), TRUE);
    gtk_widget_show (widget);

    if ((button = tool_item_get_button (widget)) != NULL)
        g_signal_connect (button, "button-release-event",
                  G_CALLBACK (tool_item_button_cb),
                  new_window_action);

    switcher->priv->proxies = g_list_append (
        switcher->priv->proxies, widget);

    gtk_widget_set_parent (widget, GTK_WIDGET (switcher));
    gtk_widget_queue_resize (GTK_WIDGET (switcher));
}

/**
 * e_shell_switcher_get_style:
 * @switcher: an #EShellSwitcher
 *
 * Returns whether @switcher has text, icons or both.
 *
 * Returns: the current style of @shell
 **/
GtkToolbarStyle
e_shell_switcher_get_style (EShellSwitcher *switcher)
{
    g_return_val_if_fail (
        E_IS_SHELL_SWITCHER (switcher),
        E_SHELL_SWITCHER_DEFAULT_TOOLBAR_STYLE);

    return switcher->priv->style;
}

/**
 * e_shell_switcher_set_style:
 * @switcher: an #EShellSwitcher
 * @style: the new style for @switcher
 *
 * Alters the view of @switcher to display either icons only, text only,
 * or both.
 **/
void
e_shell_switcher_set_style (EShellSwitcher *switcher,
                            GtkToolbarStyle style)
{
    g_return_if_fail (E_IS_SHELL_SWITCHER (switcher));

    switcher->priv->style_set = TRUE;
    g_signal_emit (switcher, signals[STYLE_CHANGED], 0, style);
}

/**
 * e_shell_switcher_unset_style:
 * @switcher: an #EShellSwitcher
 *
 * Unsets a switcher style set with e_shell_switcher_set_style(), so
 * that user preferences will be used to determine the switcher style.
 **/
void
e_shell_switcher_unset_style (EShellSwitcher *switcher)
{
    GtkSettings *settings;
    GtkToolbarStyle style;

    g_return_if_fail (E_IS_SHELL_SWITCHER (switcher));

    if (!switcher->priv->style_set)
        return;

    settings = switcher->priv->settings;
    if (settings != NULL)
        g_object_get (settings, "gtk-toolbar-style", &style, NULL);
    else
        style = E_SHELL_SWITCHER_DEFAULT_TOOLBAR_STYLE;

    if (style == GTK_TOOLBAR_BOTH)
        style = GTK_TOOLBAR_BOTH_HORIZ;

    if (style != switcher->priv->style)
        g_signal_emit (switcher, signals[STYLE_CHANGED], 0, style);

    switcher->priv->style_set = FALSE;
}

/**
 * e_shell_switcher_get_visible:
 * @switcher: an #EShellSwitcher
 *
 * Returns %TRUE if the switcher buttons are visible.
 *
 * Note that switcher button visibility is different than
 * @switcher<!-- -->'s GTK_VISIBLE flag, since #EShellSwitcher
 * is actually a container widget for #EShellSidebar.
 *
 * Returns: %TRUE if the switcher buttons are visible
 **/
gboolean
e_shell_switcher_get_visible (EShellSwitcher *switcher)
{
    g_return_val_if_fail (E_IS_SHELL_SWITCHER (switcher), FALSE);

    return switcher->priv->toolbar_visible;
}

/**
 * e_shell_switcher_set_visible:
 * @switcher: an #EShellSwitcher
 * @visible: whether the switcher buttons should be visible
 *
 * Sets the switcher button visiblity to @visible.
 *
 * Note that switcher button visibility is different than
 * @switcher<!-- -->'s GTK_VISIBLE flag, since #EShellSwitcher
 * is actually a container widget for #EShellSidebar.
 **/
void
e_shell_switcher_set_visible (EShellSwitcher *switcher,
                              gboolean visible)
{
    GList *iter;

    g_return_if_fail (E_IS_SHELL_SWITCHER (switcher));

    switcher->priv->toolbar_visible = visible;

    for (iter = switcher->priv->proxies; iter != NULL; iter = iter->next)
        g_object_set (iter->data, "visible", visible, NULL);

    gtk_widget_queue_resize (GTK_WIDGET (switcher));

    g_object_notify (G_OBJECT (switcher), "toolbar-visible");
}