From b77b2ae440886746e35985768d3b4785eab62ee7 Mon Sep 17 00:00:00 2001
From: "Manu Mtz.-Almeida" <manu.valladolid@gmail.com>
Date: Tue, 15 Nov 2016 10:42:03 +0100
Subject: [PATCH] fix(nav): willLeave is called before willEnter

fixes #9163
---
 src/navigation/nav-controller-base.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/navigation/nav-controller-base.ts b/src/navigation/nav-controller-base.ts
index a23bd629935..011ceba9d43 100644
--- a/src/navigation/nav-controller-base.ts
+++ b/src/navigation/nav-controller-base.ts
@@ -656,9 +656,9 @@ export class NavControllerBase extends Ion implements NavController {
   _viewsWillLifecycles(enteringView: ViewController, leavingView: ViewController) {
     if (enteringView || leavingView) {
       this._zone.run(() => {
-        // call each view's lifecycle events
-        enteringView && this._willEnter(enteringView);
+        // Here, the order is important. WillLeave must called before WillEnter.
         leavingView && this._willLeave(leavingView);
+        enteringView && this._willEnter(enteringView);
       });
     }
   }