hide other flash messages before showing a new one

app/assets/javascripts/widgets/flash-messages.js

@@ -7,13 +7,12 @@
     });
 
     this.animateMessages = function() {
-      var flashMessages = $("#flash_notice, #flash_error, #flash_alert");
-      flashMessages.addClass("expose");
-      flashMessages.delay(8000);
-			flashMessages.fadeTo(200, 0.5);
+      self.flashMessages().addClass("expose").delay(8000).fadeTo(200, 0.5);
     };
 
     this.render = function(result) {
+      self.flashMessages().removeClass("expose").hide();
+
       $("<div/>", {
         id: result.success ? "flash_notice" : "flash_error"
       })
@@ -23,8 +22,13 @@
         .html(result.notice))
       .prependTo(document.body);
 
+
       self.animateMessages();
     };
+
+    this.flashMessages = function() {
+      return $("#flash_notice, #flash_error, #flash_alert");
+    };
   };
 
   Diaspora.Widgets.FlashMessages = FlashMessages;