docs: update docs and demo

README.md

@@ -110,11 +110,11 @@ Type: Bool Default: true
 
 ONLY SET THIS TO `false` IF YOU SET `wheel` PROPS `true`.
 
-### wheel
+### overflow
 
 Type: Bool Default: false
 
-For overflow containers, scroll event not propagated to `window`, so you should use `wheel` props to make LazyLoad listen `wheel` event instead of `scroll`. Check [this demo](https://jasonslyvia.github.io/react-lazyload/examples/overflow.html) for detail.
+If lazy loading components inside a overflow container, set this to `true`. Also make sure a `position` property other than `static` has been set to your overflow container.
 
 ### resize
 

examples/index.html

@@ -21,8 +21,10 @@
     counter-reset: widgets;
   }
   .widget-list.overflow {
+    position: relative;
     height: 500px;
     overflow-y: scroll;
+    -webkit-overflow-scrolling: touch;
   }
   .widget {
     position: relative;

examples/pages/overflow.js

@@ -40,7 +40,7 @@ export default class Overflow extends Component {
         <div className="widget-list overflow">
           {this.state.arr.map((el, index) => {
             return (
-              <LazyLoad once={el.once} key={index} wheel={true} scroll={false}>
+              <LazyLoad once={el.once} key={index} overflow throttle={100}>
                 <Widget once={el.once} id={el.uniqueId} />
               </LazyLoad>
             );