Fixed 'jurky` navigation between pages in iOS.

Fixed after application suspend/resume the UI was not restored.
Fixed modal-views page

apps/modal-views-demo/main-page.ts

@@ -1,67 +1,62 @@
-import observable = require("data/observable");
-import pages = require("ui/page");
-import labelModule = require("ui/label");
+import {EventData} from "data/observable";
+import {Page} from "ui/page";
+import {Label} from "ui/label";
 import frame = require("ui/frame");
 
-var page: pages.Page;
-var label: labelModule.Label;
-
-export function onNavigatingTo(args: observable.EventData) {
+export function onNavigatingTo(args: EventData) {
     console.log(">>> main-page.onNavigatingTo");
     //console.trace();
 }
 
-export function onLoaded(args: observable.EventData) {
+export function onLoaded(args: EventData) {
     console.log(">>> main-page.onLoaded");
     //console.trace();
-    if (args.object !== frame.topmost().currentPage) {
-        throw new Error("args.object must equal frame.topmost().currentPage on page.loaded");
-    }
-    page = <pages.Page>args.object;
-    label = frame.topmost().getViewById<labelModule.Label>("label");
-    if (!label) {
-        throw new Error("Could not find `label`");
-    }
 }
 
-export function onNavigatedTo(args: observable.EventData) {
+export function onNavigatedTo(args: EventData) {
     console.log(">>> main-page.onNavigatedTo");
     //console.trace();
 }
 
-export function onNavigatingFrom(args: observable.EventData) {
+export function onNavigatingFrom(args: EventData) {
     console.log(">>> main-page.onNavigatingFrom");
 }
 
-export function onNavigatedFrom(args: observable.EventData) {
+export function onNavigatedFrom(args: EventData) {
     console.log(">>> main-page.onNavigatedFrom");
 }
 
-export function onUnloaded(args: observable.EventData) {
+export function onUnloaded(args: EventData) {
     console.log(">>> main-page.onUnloaded");
 }
 
-export function onTap(args: observable.EventData) {
+export function onTap(args: EventData) {
+    let page = (<any>args.object).page;
     if ((<any>args.object).text.indexOf("(navigate)") !== -1) {
         var entry: frame.NavigationEntry = {
             moduleName: "./login-page",
             context: "Context from navigate"
         };
-        frame.topmost().navigate(entry);
+       
+        page.frame.navigate(entry);
     }
     else {
         var fullscreen = (<any>args.object).text.indexOf("(full-screen)") !== -1;
-        showModal(fullscreen);
+        showModal(page, fullscreen);
     }
 }
 
-function showModal(fullscreen?: boolean) {
+function showModal(page: Page, fullscreen?: boolean) {
     page.showModal("./modal-views-demo/login-page", "Context from showModal", function (username: string, password: string) {
         console.log(username + "/" + password);
-        label.text = username + "/" + password;
+        let label = page.getViewById<Label>("label");
+        if (label) {
+            label.text = username + "/" + password;
+        }
     }, fullscreen);
 }
 
-export function onCloseModal(args: observable.EventData) {
+export function onCloseModal(args: EventData) {
+    let page = (<any>args.object).page;
     page.closeModal();
 }

ui/frame/frame.android.ts

@@ -184,7 +184,7 @@ function onFragmentHidden(fragment) {
 export class Frame extends frameCommon.Frame {
     private _android: AndroidFrame;
     private _delayedNavigationEntry: definition.BackstackEntry;
-    private _containerViewId: number;
+    private _containerViewId: number = -1;
     private _listener: android.view.View.OnAttachStateChangeListener;
     constructor() {
         super();
@@ -379,7 +379,10 @@ export class Frame extends frameCommon.Frame {
 
     public _createUI() {
         let root = new org.nativescript.widgets.ContentLayout(this._context);
-        this._containerViewId = android.view.View.generateViewId();
+        if (this._containerViewId < 0) {
+            this._containerViewId = android.view.View.generateViewId();
+        }
+
         this._android.rootViewGroup = root;
         this._android.rootViewGroup.setId(this._containerViewId);
         this._android.rootViewGroup.addOnAttachStateChangeListener(this._listener);

ui/frame/frame.ios.ts

@@ -166,7 +166,7 @@ export class Frame extends frameCommon.Frame {
                     newValue = !page.actionBarHidden;
                 }
                 else {
-                    newValue = this.backStack.length > 0 || (page && page.actionBar && !page.actionBar._isEmpty());
+                    newValue = this.ios.controller.viewControllers.count > 1 || (page && page.actionBar && !page.actionBar._isEmpty());
                 }
 
                 newValue = !!newValue; // Make sure it is boolean
@@ -174,7 +174,7 @@ export class Frame extends frameCommon.Frame {
         }
     }
 
-    public get ios(): definition.iOSFrame {
+    public get ios(): iOSFrame {
         return this._ios;
     }
 
@@ -706,7 +706,7 @@ class iOSFrame implements definition.iOSFrame {
     public set showNavigationBar(value: boolean) {
         var change = this._showNavigationBar !== value;
         this._showNavigationBar = value;
-        this._controller.navigationBarHidden = !value;
+        this._controller.setNavigationBarHiddenAnimated(!value, true);
 
         let currentPage = this._controller.owner.currentPage;
         if (currentPage && change) {

ui/list-view/list-view.android.ts

@@ -43,14 +43,14 @@ function onSeparatorColorPropertyChanged(data: dependencyObservable.PropertyChan
 export class ListView extends common.ListView {
     private _android: android.widget.ListView;
     public _realizedItems = {};
-    private _androidViewId: number;
+    private _androidViewId: number = -1;
 
     public _createUI() {
         this._android = new android.widget.ListView(this._context);
 
         // Fixes issue with black random black items when scrolling
         this._android.setCacheColorHint(android.graphics.Color.TRANSPARENT);
-        if (!this._androidViewId) {
+        if (this._androidViewId < 0) {
             this._androidViewId = android.view.View.generateViewId();
         }
         this._android.setId(this._androidViewId);

ui/scroll-view/scroll-view.android.ts

@@ -12,7 +12,7 @@ common.orientationProperty.metadata.onValueChanged = function scrollViewOrientat
 
 export class ScrollView extends common.ScrollView implements definition.ScrollView {
     private _android: org.nativescript.widgets.VerticalScrollView | org.nativescript.widgets.HorizontalScrollView;
-    private _androidViewId: number;
+    private _androidViewId: number = -1;
     private handler: android.view.ViewTreeObserver.OnScrollChangedListener;
 
     get android(): android.view.ViewGroup {
@@ -86,7 +86,7 @@ export class ScrollView extends common.ScrollView implements definition.ScrollVi
             this._android = new org.nativescript.widgets.VerticalScrollView(this._context);
         }
 
-        if (!this._androidViewId) {
+        if (this._androidViewId < 0) {
             this._androidViewId = android.view.View.generateViewId();
         }
 

ui/tab-view/tab-view.android.ts

@@ -191,7 +191,7 @@ export class TabView extends common.TabView {
     private _tabLayout: org.nativescript.widgets.TabLayout;
     private _viewPager: android.support.v4.view.ViewPager;
     private _pagerAdapter: android.support.v4.view.PagerAdapter;
-    private _androidViewId: number;
+    private _androidViewId: number = -1;
 
     private _pageChagedListener: android.support.v4.view.ViewPager.SimpleOnPageChangeListener;
 
@@ -227,7 +227,7 @@ export class TabView extends common.TabView {
         this._viewPager.setLayoutParams(lp);
         this._grid.addView(this._viewPager);
 
-        if (!this._androidViewId) {
+        if (this._androidViewId < 0) {
             this._androidViewId = android.view.View.generateViewId();
         }
         this._grid.setId(this._androidViewId);