Add innerContainerStyle that styles the sortable section and not the header and footer (#92)

ok, thanks for contribution, will release it soon

Author: jcurtis

README.md

@@ -29,6 +29,7 @@ npm i react-native-sortable-list --save
 - **order?** (Array) an array of keys from data, the order of keys from the array will be used to initial rows order
 - **style?** (Object, Array)
 - **contentContainerStyle?** (Object, Array) these styles will be applied to the inner scroll view content container
+- **innerContainerStyle?** (Object, Array) these styles will be applied to the inner scroll view content container, excluding the header and footer
 - **horizontal?** (boolean) when true, the SortableList's children are arranged horizontally in a row instead of vertically in a column. The default value is false.
 - **sortingEnabled?** (boolean) when false, rows are not sortable. The default value is true.
 - **scrollEnabled?** (boolean) when false, the content does not scrollable. The default value is true.

src/SortableList.js

@@ -15,10 +15,11 @@ uniqueRowKey.id = 0
 
 export default class SortableList extends Component {
   static propTypes = {
-    data: PropTypes.oneOfType([PropTypes.array, PropTypes.object]).isRequired, 
+    data: PropTypes.oneOfType([PropTypes.array, PropTypes.object]).isRequired,
     order: PropTypes.arrayOf(PropTypes.any),
     style: ViewPropTypes.style,
     contentContainerStyle: ViewPropTypes.style,
+    innerContainerStyle: ViewPropTypes.style,
     sortingEnabled: PropTypes.bool,
     scrollEnabled: PropTypes.bool,
     horizontal: PropTypes.bool,
@@ -173,12 +174,13 @@ export default class SortableList extends Component {
   }
 
   render() {
-    const {contentContainerStyle, horizontal, style} = this.props;
+    let {contentContainerStyle, innerContainerStyle, horizontal, style} = this.props;
     const {animated, contentHeight, contentWidth, scrollEnabled} = this.state;
     const containerStyle = StyleSheet.flatten([style, {opacity: Number(animated)}])
-    const innerContainerStyle = [
+    innerContainerStyle = [
       styles.rowsContainer,
       horizontal ? {width: contentWidth} : {height: contentHeight},
+      innerContainerStyle
     ];
     let {refreshControl} = this.props;