WorkspaceSidebar: Improve add button

gajim/data/style/gajim.css

@@ -171,18 +171,14 @@ .workspace-sidebar-item.drag-hover-top {
 .workspace-sidebar-item.drag-hover-bottom {
     border-bottom: 1px solid #4e9a06;
 }
-.workspace-add {
-    padding: 0 0 0 6px;
-    margin: 6px 12px;
-}
-.workspace-add image {
-    margin: 0px;
-    padding: 0px;
-    color: alpha(@theme_text_color, 0.7);
-    background-color: shade(@theme_base_color, 0.9);
+.workspace-add:hover,
+.workspace-add:focus {
+    background: transparent;
+    box-shadow: none;
+    outline: none;
 }
-.workspace-add:hover image {
-    background-color: shade(@theme_base_color, 0.85);
+.workspace-add button {
+    margin: 6px 8px 6px 14px;
 }
 
 /* Account sidebar */

gajim/gtk/workspace_side_bar.py

@@ -206,14 +206,13 @@ def update_avatar(self, workspace_id):
 class CommonWorkspace(Gtk.ListBoxRow):
     def __init__(self, workspace_id):
         Gtk.ListBoxRow.__init__(self)
-        self.get_style_context().add_class('workspace-sidebar-item')
-
         self.workspace_id = workspace_id
 
 
 class Workspace(CommonWorkspace):
     def __init__(self, workspace_id):
         CommonWorkspace.__init__(self, workspace_id)
+        self.get_style_context().add_class('workspace-sidebar-item')
 
         self._unread_label = Gtk.Label()
         self._unread_label.get_style_context().add_class(
@@ -286,12 +285,16 @@ def __init__(self, workspace_id):
         self.set_selectable(False)
         self.set_tooltip_text(_('Add Workspace'))
         self.get_style_context().add_class('workspace-add')
-
-        image = Gtk.Image.new_from_icon_name('list-add-symbolic',
-                                             Gtk.IconSize.DND)
-        self.add(image)
+        button = Gtk.Button.new_from_icon_name('list-add-symbolic',
+                                               Gtk.IconSize.BUTTON)
+        button.connect('clicked', self._on_add_clicked)
+        self.add(button)
         self.show_all()
 
+    @staticmethod
+    def _on_add_clicked(_button):
+        open_window('WorkspaceDialog')
+
 
 class WorkspaceAvatar(Gtk.Image):
     def __init__(self, workspace_id):