add joysick support and state feedback

src/items/itemstore.cpp

@@ -7,6 +7,11 @@ ItemStore::ItemStore(QObject *parent): QObject(parent)
 
 void ItemStore::addItem(std::shared_ptr<Item> item)
 {
+	if(!item)
+	{
+		qWarning()<<"invalid item";
+		return;
+	}
     bool mached = false;
     for(unsigned i = 0; i < items_.size(); i++ )
         if(*items_[i] == *item) mached = true;