Merge pull request #190 from tbenbrahim/master

Fixes #189, clear should not remove label, error label and listbox

Author: kevzlou7979

src/main/java/gwt/material/design/addins/client/combobox/MaterialComboBox.java

@@ -46,6 +46,7 @@
 
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Iterator;
 import java.util.List;
 
 import static gwt.material.design.addins.client.combobox.js.JsComboBox.$;
@@ -211,6 +212,17 @@ public void add(Widget child) {
         listbox.add(child);
     }
 
+    @Override
+    public void clear() {
+        final Iterator<Widget> it = iterator();
+        while (it.hasNext()) {
+        	final Widget widget = it.next();
+        	if (widget != label && widget != lblError && widget != listbox) {
+	            it.remove();
+        	}
+        }
+    }
+
     /**
      * Sets multi-value select boxes.
      */
@@ -582,4 +594,4 @@ public MaterialWidget getListbox() {
     public Label getLabel() {
         return label;
     }
-}
+}