Sign button is unsensitive when nothing chosen

source/ubl-settings-repomanager.c

@@ -363,6 +363,7 @@ void on_tree_selection_changed(GtkWidget *self,main_window *widgets){
             gtk_widget_set_sensitive(widgets->DeleteButton,1);
             gtk_widget_set_sensitive(widgets->AddPackageButton,1);
             gtk_widget_set_sensitive(widgets->RemovePackageButton,0);
+            gtk_widget_set_sensitive(widgets->SignButton,1);
             gtk_widget_set_visible(widgets->NameBox,1);
             gtk_widget_set_visible(widgets->DependenceBox,0);
             gtk_widget_set_visible(widgets->VersionBox,0);
@@ -375,6 +376,7 @@ void on_tree_selection_changed(GtkWidget *self,main_window *widgets){
             gtk_widget_set_sensitive(widgets->DeleteButton,0);
             gtk_widget_set_sensitive(widgets->AddPackageButton,1);
             gtk_widget_set_sensitive(widgets->RemovePackageButton,1);
+            gtk_widget_set_sensitive(widgets->SignButton,1);
             gtk_widget_set_visible(widgets->NameBox,1);
             gtk_widget_set_visible(widgets->DependenceBox,1);
             gtk_widget_set_visible(widgets->VersionBox,1);
@@ -388,6 +390,7 @@ void on_tree_selection_changed(GtkWidget *self,main_window *widgets){
         gtk_widget_set_sensitive(widgets->DeleteButton,0);
         gtk_widget_set_sensitive(widgets->AddPackageButton,0);
         gtk_widget_set_sensitive(widgets->RemovePackageButton,0);
+        gtk_widget_set_sensitive(widgets->SignButton,0);
         gtk_widget_set_visible(widgets->NameBox,0);
         gtk_widget_set_visible(widgets->DependenceBox,0);
         gtk_widget_set_visible(widgets->VersionBox,0);

ubl-settings-repomanager.glade

@@ -725,7 +725,7 @@ translated and supported by community.</property>
                                         <property name="visible">True</property>
                                         <property name="can-focus">True</property>
                                         <property name="receives-default">True</property>
-                                        <property name="tooltip-text" translatable="yes">Create repository</property>
+                                        <property name="tooltip-text" translatable="yes">Open or create repository</property>
                                         <property name="image">image1</property>
                                         <style>
                                           <class name="thin"/>
@@ -801,6 +801,7 @@ translated and supported by community.</property>
                                     <child>
                                       <object class="GtkButton" id="SignButton">
                                         <property name="visible">True</property>
+                                        <property name="sensitive">False</property>
                                         <property name="can-focus">True</property>
                                         <property name="receives-default">True</property>
                                         <property name="tooltip-text" translatable="yes">Sign</property>