[evolution] Bug 737330 - EShellSwitcher: Count with GtkPaned::handle-size for button widths

[Milan Crha <mcrha src gnome org>]

commit a20e862582c8577bdaf001b374cbbb7eb8ca396d
Author: Milan Crha <mcrha redhat com>
Date:   Tue Oct 14 12:06:14 2014 +0200

    Bug 737330 - EShellSwitcher: Count with GtkPaned::handle-size for button widths
    
    Gtk+ 3.10 has the GtkPaned::handle-size set to 5 pixels, while Gtk+ 3.14
    only to 1 pixel, which makes the right side of the EShellSwitcher buttons
    look as with no padding on the right.

 shell/e-shell-switcher.c |   53 ++++++++++++++++++++++++++++++++++++++-------
 1 files changed, 44 insertions(+), 9 deletions(-)
---
diff --git a/shell/e-shell-switcher.c b/shell/e-shell-switcher.c
index a4d6394..a979919 100644
--- a/shell/e-shell-switcher.c
+++ b/shell/e-shell-switcher.c
@@ -53,6 +53,7 @@ struct _EShellSwitcherPrivate {
        GtkSettings *settings;
        gulong settings_handler_id;
        gboolean toolbar_visible;
+       gint hpaned_handle_size;
 };
 
 enum {
@@ -115,7 +116,7 @@ shell_switcher_layout_actions (EShellSwitcher *switcher)
        }
 
        /* Figure out how many rows and columns we'll use. */
-       btns_per_row = MAX (1, allocation.width / (max_width + H_PADDING));
+       btns_per_row = MAX (1, (allocation.width - 1) / (max_width + H_PADDING + H_PADDING - 
switcher->priv->hpaned_handle_size));
        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
@@ -150,20 +151,22 @@ shell_switcher_layout_actions (EShellSwitcher *switcher)
 
        /* Layout the buttons. */
        for (i = row_last; i >= 0; i--) {
-               gint len, extra_width;
+               gint len, extra_width, left_width;
 
+               left_width = allocation.width - 1;
                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) {
+               for (p = rows[i]; p != NULL; p = p->next, len--) {
                        GtkAllocation child_allocation;
 
+                       if (!icons_only)
+                               extra_width =
+                                       (left_width - (len * max_width) -
+                                       (len * H_PADDING + H_PADDING - switcher->priv->hpaned_handle_size)) / 
len;
+                       else
+                               extra_width = 0;
+
                        child_allocation.x = x;
                        child_allocation.y = y;
                        child_allocation.width = max_width + extra_width;
@@ -173,6 +176,7 @@ shell_switcher_layout_actions (EShellSwitcher *switcher)
                                GTK_WIDGET (p->data), &child_allocation);
 
                        x += child_allocation.width + H_PADDING;
+                       left_width = left_width - child_allocation.width - H_PADDING;
                }
 
                y -= V_PADDING;
@@ -451,6 +455,31 @@ shell_switcher_style_changed (EShellSwitcher *switcher,
        g_object_notify (G_OBJECT (switcher), "toolbar-style");
 }
 
+static void
+shell_switcher_read_handle_size (EShellSwitcher *switcher)
+{
+       GtkWidget *paned;
+
+       g_return_if_fail (E_IS_SHELL_SWITCHER (switcher));
+
+       paned = gtk_paned_new (GTK_ORIENTATION_HORIZONTAL);
+       gtk_widget_style_get (paned, "handle-size", &switcher->priv->hpaned_handle_size, NULL);
+       gtk_widget_destroy (paned);
+
+       if (switcher->priv->hpaned_handle_size < 0)
+               switcher->priv->hpaned_handle_size = 0;
+       else if (switcher->priv->hpaned_handle_size > H_PADDING)
+               switcher->priv->hpaned_handle_size = H_PADDING;
+}
+
+static void
+shell_switcher_style_updated_cb (EShellSwitcher *switcher)
+{
+       g_return_if_fail (E_IS_SHELL_SWITCHER (switcher));
+
+       shell_switcher_read_handle_size (switcher);
+}
+
 static GtkIconSize
 shell_switcher_get_icon_size (GtkToolShell *shell)
 {
@@ -568,6 +597,12 @@ e_shell_switcher_init (EShellSwitcher *switcher)
        gtk_widget_set_has_window (GTK_WIDGET (switcher), FALSE);
 
        e_extensible_load_extensions (E_EXTENSIBLE (switcher));
+
+       switcher->priv->hpaned_handle_size = 5;
+
+       shell_switcher_read_handle_size (switcher);
+
+       g_signal_connect (switcher, "style-updated", G_CALLBACK (shell_switcher_style_updated_cb), NULL);
 }
 
 static void