Merge pull request #105 from charpeni/fix-98

Fix PR #98

Author: davidLeonardi

components/NavBarContent.js

@@ -173,11 +173,11 @@ class NavBarContent extends React.Component {
       );
     } else if (this.props.route.index > 0) {
       leftCornerContent = (
-        <NavButton onPress={this.goBack } backButtonComponent={ () => {
-          const BackButton = this.props.backButtonComponent;
-          const backButtonProps = this.props.route.backButtonProps || {};
-          return <BackButton {...backButtonProps} />;
-        }} />
+        <NavButton
+          onPress={this.goBack}
+          backButtonComponent={this.props.backButtonComponent}
+          {...this.props.route.backButtonProps}
+        />
       );
     }