first import

sites/all/modules/geocoder/geocoder.admin.js

@@ -0,0 +1,42 @@
+(function ($) {
+
+  Drupal.behaviors.geocoderWidgetSettings = {
+    attach: function (context, settings) {
+      $(':input[name="instance[widget][settings][geocoder_field]"]', context).once('geofield_widget_settings', function () {
+        // When the geocoder_field field is changed, update the geocoder_handler options.
+        $(this).change(function() {
+          var field = $(this).val();
+          var field_type = settings.geocoder_widget_settings.types[field];
+          var valid_handlers = settings.geocoder_widget_settings.handlers[field_type];
+          $(':input[name="instance[widget][settings][geocoder_handler]"] option', context).each(function () {
+            var handler_type = $(this).val();
+            if (geocoder_admin_handler_in_array(handler_type, valid_handlers)) {
+              $(this).removeAttr('disabled').show();
+            }
+            else {
+              $(this).attr('disabled', 'disabled').hide();
+            }
+          });
+
+          // If the currently selected handler is not valid, set it to the first valid handler.
+          // Trigger a change event so that depdendent fields will update.
+          if (!geocoder_admin_handler_in_array($(':input[name="instance[widget][settings][geocoder_handler]"]').val(), valid_handlers)) {
+            $('#:input[name="instance[widget][settings][geocoder_handler]"]').val(valid_handlers[0]).trigger('change');
+          }
+        });
+
+        function geocoder_admin_handler_in_array(needle, haystack) {
+          var length = haystack.length;
+          for(var i = 0; i < length; i++) {
+            if(haystack[i] == needle) return true;
+          }
+          return false;
+        }
+      });
+      // Trigger an initial change event to initialize the dependent field.
+      $(this).trigger('change');
+    }
+  };
+
+})(jQuery);
+