Lazy-load dashboard widgets

src/pretix/static/pretixcontrol/js/ui/dashboard.js

@@ -0,0 +1,13 @@
+/*global $,gettext*/
+
+$(function () {
+    if ($("div[data-lazy-id]").length == 0) {
+        return;
+    }
+    $.getJSON("widgets.json", function (data) {
+        $.each(data.widgets, function (k, v) {
+            $("[data-lazy-id=" + v.lazy + "]").removeClass("widget-lazy-loading");
+            $("[data-lazy-id=" + v.lazy + "] .widget").html(v.content);
+        });
+    });
+});

src/pretix/static/pretixcontrol/scss/_dashboard.scss

@@ -27,6 +27,16 @@
   width: 25%;
 }
 
+.dashboard .widget-container.widget-lazy-loading {
+  text-align: center;
+  .fa-cog {
+    color: #ccc;
+    margin-top: 30px;
+    -webkit-animation: fa-spin 4s infinite linear;
+    animation: fa-spin 4s infinite linear;
+  }
+}
+
 .dashboard-panels .panel-heading .fa {
   opacity: 0.5;
 }