From 5c6f76ce1eb4b6e82565f367142cf78a33604d91 Mon Sep 17 00:00:00 2001
From: Lane Rettig <lockehart@gmail.com>
Date: Tue, 12 Jan 2016 15:51:31 -0500
Subject: [PATCH] add onLeft and leftTitle to match onRight, rightTitle

---
 ExRouter.js | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/ExRouter.js b/ExRouter.js
index 5a1ebaf66..511f513c8 100644
--- a/ExRouter.js
+++ b/ExRouter.js
@@ -86,6 +86,16 @@ export class ExRouteAdapter {
     }
 
     renderLeftButton(navigator, index, state){
+        if (this.route.props.onLeft && this.route.props.leftTitle) {
+            return (<TouchableOpacity
+              touchRetentionOffset={ExNavigator.Styles.barButtonTouchRetentionOffset}
+              onPress={() => this.route.props.onLeft({...this.route.props, ...this.props})}
+              style={[ExNavigator.Styles.barLeftButton, this.route.props.leftButtonStyle]}>
+                <Text
+                  style={[ExNavigator.Styles.barLeftButtonText, this.route.props.leftButtonTextStyle]}>{this.route.props.leftTitle}</Text>
+            </TouchableOpacity>);
+        }
+        
         if (index === 0 || index < navigator.getCurrentRoutes().length-1) {
             return null;
         }