change the event accordingly

src/store/index.js

@@ -6,6 +6,18 @@ Vue.use(Vuex);
 export default new Vuex.Store({
   state: {
     events: ['35c3', 'camp19', '36c3'],
-    activeEvent: '35c3'
+    activeEvent: '36c3',
+    loadedItems: []
+  },
+  mutations: {
+    changeEvent(state, event) {
+      state.activeEvent = event;
+    }
+  },
+  actions: {
+    changeEvent({ commit }, event) {
+      // todo: load items from server
+      commit('changeEvent', event);
+    }
   }
 });