add LoadingBar component

add LoadingBar component

components/loading-bar/loading-bar.js

@@ -0,0 +1,42 @@
+import LoadingBar from './loading-bar.vue';
+import Vue from 'vue';
+import { camelcaseToHyphen } from '../../utils/assist';
+
+LoadingBar.newInstance = properties => {
+    const _props = properties || {};
+
+    let props = '';
+    Object.keys(_props).forEach(prop => {
+        props += ' :' + camelcaseToHyphen(prop) + '=' + prop;
+    });
+
+    const div = document.createElement('div');
+    div.innerHTML = `<loading-bar${props}></loading-bar>`;
+    document.body.appendChild(div);
+
+    const loading_bar = new Vue({
+        el: div,
+        data: _props,
+        components: { LoadingBar }
+    }).$children[0];
+
+    return {
+        update (options) {
+            if ('percent' in options) {
+                loading_bar.percent = options.percent;
+            }
+            if (options.status) {
+                loading_bar.status = options.status;
+            }
+            if ('show' in options) {
+                loading_bar.show = options.show;
+            }
+        },
+        component: loading_bar,
+        destroy () {
+            document.body.removeChild(div);
+        }
+    }
+};
+
+export default LoadingBar;