clear search button

gui/griffon-app/controllers/com/muwire/gui/MainFrameController.groovy

@@ -51,6 +51,13 @@ class MainFrameController {
 
     private volatile Core core
 
+    @ControllerAction
+    void clearSearch() {
+        def searchField = builder.getVariable("search-field")
+        searchField.setSelectedItem(null)
+        searchField.requestFocus()
+    }
+    
     @ControllerAction
     void search(ActionEvent evt) {
         if (evt?.getActionCommand() == null)

gui/griffon-app/views/com/muwire/gui/MainFrameView.groovy

@@ -154,6 +154,7 @@ class MainFrameView {
                             }
                             panel( constraints: BorderLayout.EAST) {
                                 button(text: "Search", searchAction)
+                                button(text : "", icon : imageIcon("/close_tab.png"), clearSearchAction)
                             }
                         }
                     }

gui/src/main/groovy/com/muwire/gui/SearchFieldModel.groovy

@@ -18,6 +18,8 @@ class SearchFieldModel extends AbstractListModel implements MutableComboBoxModel
     }
     
     public void addElement(Object string) {
+        if (string == null)
+            return
         if (uiSettings.storeSearchHistory) {
             if (!uiSettings.searchHistory.add(string))
                 return