update TimePicker & BackTop

update TimePicker & BackTop

src/utils/assist.js

@@ -86,7 +86,7 @@ function firstUpperCase(str) {
 export function warnProp(component, prop, correctType, wrongType) {
     correctType = firstUpperCase(correctType);
     wrongType = firstUpperCase(wrongType);
-    console.error(`[iView warn]: Invalid prop: type check failed for prop ${prop}. Expected ${correctType}, got ${wrongType}. (found in component: ${component})`);
+    console.error(`[iView warn]: Invalid prop: type check failed for prop ${prop}. Expected ${correctType}, got ${wrongType}. (found in component: ${component})`);    // eslint-disable-line
 }
 
 function typeOf(obj) {
@@ -131,4 +131,37 @@ function deepCopy(data) {
     return o;
 }
 
-export {deepCopy};
+export {deepCopy};
+
+// scrollTop animation
+export function scrollTop(el, from = 0, to, duration = 500) {
+    if (!window.requestAnimationFrame) {
+        window.requestAnimationFrame = (
+            window.webkitRequestAnimationFrame ||
+            window.mozRequestAnimationFrame ||
+            window.msRequestAnimationFrame ||
+            function (callback) {
+                return window.setTimeout(callback, 1000/60);
+            }
+        )
+    }
+    const difference = Math.abs(from - to);
+    const step = Math.ceil(difference / duration * 50);
+
+    function scroll(start, end, step) {
+        if (start === end) return;
+
+        let d = (start + step > end) ? end : start + step;
+        if (start > end) {
+            d = (start - step < end) ? end : start - step;
+        }
+
+        if (el === window) {
+            window.scrollTo(d, d);
+        } else {
+            el.scrollTop = d;
+        }
+        window.requestAnimationFrame(() => scroll(d, end, step));
+    }
+    scroll(from, to, step);
+}