add LoadingBar component

add LoadingBar component

components/loading-bar/index.js

@@ -0,0 +1,110 @@
+import LoadingBar from './loading-bar';
+
+let loadingBarInstance;
+let color = 'primary';
+let failedColor = 'error';
+let height = 2;
+let timer;
+
+function getLoadingBarInstance () {
+    loadingBarInstance = loadingBarInstance || LoadingBar.newInstance({
+        color: color,
+        failedColor: failedColor,
+        height: height
+    });
+
+    return loadingBarInstance;
+}
+
+function update(options) {
+    let instance  = getLoadingBarInstance();
+
+    instance.update(options);
+}
+
+function hide() {
+    setTimeout(() => {
+        update({
+            show: false
+        });
+        setTimeout(() => {
+            update({
+                percent: 0
+            });
+        }, 200)
+    }, 800);
+}
+
+function clearTimer() {
+    if (timer) {
+        clearInterval(timer);
+        timer = null;
+    }
+}
+
+export default {
+    start () {
+        let percent = 0;
+
+        update({
+            percent: percent,
+            status: 'success',
+            show: true
+        });
+
+        timer = setInterval(() => {
+            percent += Math.floor(Math.random () * 3 + 5);
+            if (percent > 95) {
+                clearTimer();
+            }
+            update({
+                percent: percent,
+                status: 'success',
+                show: true
+            });
+        }, 200);
+    },
+    update (percent) {
+        clearTimer();
+        update({
+            percent: percent,
+            status: 'success',
+            show: true
+        });
+    },
+    finish () {
+        clearTimer();
+        update({
+            percent: 100,
+            status: 'success',
+            show: true
+        });
+        hide();
+    },
+    error () {
+        clearTimer();
+        update({
+            percent: 100,
+            status: 'error',
+            show: true
+        });
+        hide();
+    },
+    config (options) {
+        if (options.color) {
+            color = options.color;
+        }
+        if (options.failedColor) {
+            failedColor = options.failedColor;
+        }
+        if (options.height) {
+            height = options.height;
+        }
+    },
+    destroy () {
+        clearTimer();
+        let instance = getLoadingBarInstance();
+        loadingBarInstance = null;
+        instance.destroy();
+    }
+}