fix(NavController): fire onPageWillUnload/DidUnload

Fixes #5507

ionic/components/nav/nav-controller.ts

@@ -802,6 +802,7 @@ export class NavController extends Ion {
       // set that it is the init leaving view
       // the first view to be removed, it should init leave
       view.state = STATE_INIT_LEAVE;
+      view.willUnload();
 
       // from the index of the leaving view, go backwards and
       // find the first view that is inactive so it can be the entering
@@ -836,7 +837,6 @@ export class NavController extends Ion {
     this._views.filter(v => v.state === STATE_REMOVE).forEach(view => {
       view.willLeave();
       view.didLeave();
-      view.didUnload();
       this._views.splice(this.indexOf(view), 1);
       view.destroy();
     });

ionic/components/nav/test/basic/index.ts

@@ -271,7 +271,9 @@ class AnotherPage {
   constructor(
     private nav: NavController,
     private viewCtrl: ViewController
-  ) {}
+  ) {
+    console.log('Page, AnotherPage, constructor', this.viewCtrl.id);
+  }
 
   pushFullPage() {
     this.nav.push(FullPage);
@@ -304,6 +306,34 @@ class AnotherPage {
     this.viewCtrl.setBackButtonText(backButtonText);
     ++this.bbCount;
   }
+
+  onPageWillEnter() {
+    console.log('Page, AnotherPage, onPageWillEnter', this.viewCtrl.id);
+  }
+
+  onPageDidEnter() {
+    console.log('Page, AnotherPage, onPageDidEnter', this.viewCtrl.id);
+  }
+
+  onPageWillLeave() {
+    console.log('Page, AnotherPage, onPageWillLeave', this.viewCtrl.id);
+  }
+
+  onPageDidLeave() {
+    console.log('Page, AnotherPage, onPageDidLeave', this.viewCtrl.id);
+  }
+
+  onPageWillUnload() {
+    console.log('Page, AnotherPage, onPageWillUnload', this.viewCtrl.id);
+  }
+
+  onPageDidUnload() {
+    console.log('Page, AnotherPage, onPageDidUnload', this.viewCtrl.id);
+  }
+
+  ngOnDestroy() {
+    console.log('Page, AnotherPage, ngOnDestroy', this.viewCtrl.id);
+  }
 }
 
 

ionic/components/nav/view-controller.ts

@@ -183,23 +183,6 @@ export class ViewController {
     return (this.index === 0);
   }
 
-  /**
-   * @private
-   */
-  addDestroy(destroyFn: Function) {
-    this._destroys.push(destroyFn);
-  }
-
-  /**
-   * @private
-   */
-  destroy() {
-    for (var i = 0; i < this._destroys.length; i++) {
-      this._destroys[i]();
-    }
-    this._destroys = [];
-  }
-
   /**
    * @private
    */
@@ -489,10 +472,21 @@ export class ViewController {
 
   /**
    * @private
-   * The view has been destroyed and its elements have been removed.
    */
-  didUnload() {
+  addDestroy(destroyFn: Function) {
+    this._destroys.push(destroyFn);
+  }
+
+  /**
+   * @private
+   */
+  destroy() {
     ctrlFn(this, 'onPageDidUnload');
+
+    for (var i = 0; i < this._destroys.length; i++) {
+      this._destroys[i]();
+    }
+    this._destroys = [];
   }
 
 }