1 files changed, 11 insertions, 0 deletions
diff --git a/js/tool.js b/js/tool.js
index d31472b..719e044 100644
--- a/js/tool.js
+++ b/js/tool.js
@@ -34,3 +34,14 @@ var Checkbox = Tool.extend({
     else       this.el.innerHTML = "_ " + this.name
   }
 })
+
+var HiddenCheckbox = Tool.extend({
+  init: function (span){
+    this.__init(span)
+    var state = this.name[0] == "o"
+    this.update(state)
+  },
+  update: function(state){
+  	this.el.innerHTML = state ? "o" : "."
+  }
+})