feat(HMR): style views at runtime (#7012)

* feat(HMR): style view at runtime

test: module root view component

test: update livesync tests

refactor: _onLivesync function

* style: remove a comment

* refactor: rename the property

tests/app/app/main-page.css

@@ -0,0 +1,3 @@
+Button {
+    color: green;
+}

tests/app/livesync/livesync-tests.ts

@@ -15,6 +15,7 @@ const mainPageCssFileName = "./app/main-page.css";
 const mainPageHtmlFileName = "./app/main-page.html";
 const mainPageXmlFileName = "./app/main-page.xml";
 
+const black = new Color("black");
 const green = new Color("green");
 
 const mainPageTemplate = `
@@ -56,7 +57,7 @@ export function test_onLiveSync_ModuleContext_Script_AppTs() {
 }
 
 export function test_onLiveSync_ModuleContext_Style_MainPageCss() {
-    _test_onLiveSync_ModuleContext({ type: "style", path: mainPageCssFileName });
+    _test_onLiveSync_ModuleContext_TypeStyle({ type: "style", path: mainPageCssFileName });
 }
 
 export function test_onLiveSync_ModuleContext_Markup_MainPageHtml() {
@@ -110,4 +111,29 @@ function _test_onLiveSync_ModuleContext(context: { type, path }) {
     const topmostFrame = frame.topmost();
     TKUnit.waitUntilReady(() => topmostFrame.currentPage && topmostFrame.currentPage.isLoaded && !topmostFrame.canGoBack());
     TKUnit.assertTrue(topmostFrame.currentPage.getViewById("label").isLoaded);
+}
+
+function _test_onLiveSync_ModuleContext_TypeStyle(context: { type, path }) {
+    const pageBeforeNavigation = helper.getCurrentPage();
+
+    const page = <Page>parse(pageTemplate);
+    helper.navigateWithHistory(() => page);
+
+    const pageBeforeLiveSync = helper.getCurrentPage();
+    pageBeforeLiveSync._moduleName = "main-page";
+    global.__onLiveSync({ type: context.type, path: context.path });
+
+    const pageAfterLiveSync = helper.getCurrentPage();
+    TKUnit.waitUntilReady(() => pageAfterLiveSync.getViewById("button").style.color.toString() === green.toString());
+
+    TKUnit.assertTrue(pageAfterLiveSync.frame.canGoBack(), "Local styles NOT applied - livesync navigation executed!");
+    TKUnit.assertEqual(pageAfterLiveSync, pageBeforeLiveSync, "Pages are different - livesync navigation executed!");
+    TKUnit.assertTrue(pageAfterLiveSync._cssState.isSelectorsLatestVersionApplied(), "Latest selectors version NOT applied!");
+
+    helper.goBack();
+
+    const pageAfterNavigationBack = helper.getCurrentPage();
+    TKUnit.assertEqual(pageAfterNavigationBack.getViewById("label").style.color, black, "App styles applied on back navigation!");
+    TKUnit.assertEqual(pageBeforeNavigation, pageAfterNavigationBack, "Pages are different - livesync navigation executed!");
+    TKUnit.assertTrue(pageAfterNavigationBack._cssState.isSelectorsLatestVersionApplied(), "Latest selectors version is NOT applied!");
 }

tests/app/testRunner.ts

@@ -168,12 +168,15 @@ allTests["VISUAL-STATE"] = visualStateTests;
 import * as valueSourceTests from "./ui/styling/value-source-tests";
 allTests["VALUE-SOURCE"] = valueSourceTests;
 
-import * as buttonTests from "./ui/button/button-tests";
-allTests["BUTTON"] = buttonTests;
-
 import * as borderTests from "./ui/border/border-tests";
 allTests["BORDER"] = borderTests;
 
+import * as builderTests from "./ui/builder/builder-tests";
+allTests["BUILDER"] = builderTests;
+
+import * as buttonTests from "./ui/button/button-tests";
+allTests["BUTTON"] = buttonTests;
+
 import * as labelTests from "./ui/label/label-tests";
 allTests["LABEL"] = labelTests;
 

tests/app/ui/builder/builder-tests.ts

@@ -0,0 +1,26 @@
+import { path } from "tns-core-modules/file-system";
+import { loadPage } from "tns-core-modules/ui/builder";
+import { assertEqual, assertNull } from "../../TKUnit";
+
+const COMPONENT_MODULE = "component-module";
+const LABEL = "label";
+
+function getViewComponent() {
+    const moduleNamePath = path.join(__dirname, COMPONENT_MODULE);
+    const fileName = path.join(__dirname, `${COMPONENT_MODULE}.xml`);
+    const view = loadPage(moduleNamePath, fileName);
+    return view;
+}
+
+export function test_view_is_module_root_component() {
+    const view = getViewComponent();
+    const actualModule = view._moduleName;
+    assertEqual(actualModule, COMPONENT_MODULE, `View<${view}> is NOT root component of module <${COMPONENT_MODULE}>.`);
+}
+
+export function test_view_is_NOT_module_root_component() {
+    const view = getViewComponent();
+    const nestedView = view.getViewById(`${LABEL}`);
+    const undefinedModule = nestedView._moduleName;
+    assertNull(undefinedModule, `View<${nestedView}> should NOT be a root component of a module.`);
+}

tests/app/ui/builder/component-module.xml

@@ -0,0 +1,3 @@
+<StackLayout>
+    <Label id="label"></Label>
+</StackLayout>

tns-core-modules/ui/builder/builder.ts

@@ -59,7 +59,9 @@ export function load(pathOrOptions: string | LoadOptions, context?: any): View {
 
 export function loadPage(moduleNamePath: string, fileName: string, context?: any): View {
     const componentModule = loadInternal(fileName, context, moduleNamePath);
-    return componentModule && componentModule.component;
+    const componentView = componentModule && componentModule.component;
+    markAsModuleRoot(componentView, moduleNamePath);
+    return componentView;
 }
 
 const loadModule = profile("loadModule", (moduleNamePath: string, entry: ViewEntry): ModuleExports => {
@@ -96,7 +98,7 @@ export const createViewFromEntry = profile("createViewFromEntry", (entry: ViewEn
     } else if (entry.moduleName) {
         // Current app full path.
         const currentAppPath = knownFolders.currentApp().path;
-        
+
         // Full path of the module = current app full path + module name.
         const moduleNamePath = path.join(currentAppPath, entry.moduleName);
         const moduleExports = loadModule(moduleNamePath, entry);
@@ -108,7 +110,7 @@ export const createViewFromEntry = profile("createViewFromEntry", (entry: ViewEn
             return viewFromBuilder(moduleNamePath, moduleExports);
         }
     }
-    
+
     throw new Error("Failed to load page XML file for module: " + entry.moduleName);
 });
 
@@ -128,14 +130,20 @@ interface ModuleExports {
 const moduleCreateView = profile("module.createView", (moduleNamePath: string, moduleExports: ModuleExports): View => {
     const view = moduleExports.createPage();
     const cssFileName = resolveFileName(moduleNamePath, "css");
-    
+
     // If there is no cssFile only appCss will be applied at loaded.
     if (cssFileName) {
         view.addCssFile(cssFileName);
     }
     return view;
 });
 
+function markAsModuleRoot(componentView: View, moduleNamePath: string): void {
+    const lastIndexOfSeparator = moduleNamePath.lastIndexOf(path.separator);
+    const moduleName = moduleNamePath.substring(lastIndexOfSeparator + 1);
+    componentView._moduleName = moduleName;
+}
+
 function loadInternal(fileName: string, context?: any, moduleNamePath?: string): ComponentModule {
     let componentModule: ComponentModule;
 

tns-core-modules/ui/core/view-base/view-base.d.ts

@@ -108,6 +108,12 @@ export abstract class ViewBase extends Observable {
     flexWrapBefore: FlexWrapBefore;
     alignSelf: AlignSelf;
 
+    /**
+     * @private
+     * Module name when the view is a module root. Otherwise, it is undefined.
+     */
+    _moduleName?: string;
+
     //@private
     /**
      * @private

tns-core-modules/ui/core/view-base/view-base.ts

@@ -244,6 +244,8 @@ export abstract class ViewBase extends Observable implements ViewBaseDefinition
     public _defaultPaddingLeft: number;
     public _isPaddingRelative: boolean;
 
+    public _moduleName: string;
+
     constructor() {
         super();
         this._domId = viewIdCounter++;
@@ -651,7 +653,7 @@ export abstract class ViewBase extends Observable implements ViewBaseDefinition
     }
 
     public resetNativeView(): void {
-        //    
+        //
     }
 
     private resetNativeViewInternal(): void {
@@ -688,7 +690,7 @@ export abstract class ViewBase extends Observable implements ViewBaseDefinition
 
         this._context = context;
 
-         // This will account for nativeView that is created in createNativeView, recycled
+        // This will account for nativeView that is created in createNativeView, recycled
         // or for backward compatability - set before _setupUI in iOS contructor.
         let nativeView = this.nativeViewProtected;
 

tns-core-modules/ui/core/view/view-common.ts

@@ -5,7 +5,7 @@ import {
 } from ".";
 
 import {
-    ViewBase, Property, booleanConverter, EventData, layout,
+    ViewBase, Property, booleanConverter, eachDescendant, EventData, layout,
     getEventOrGestureName, traceEnabled, traceWrite, traceCategories,
     InheritedProperty,
     ShowModalOptions
@@ -136,6 +136,37 @@ export abstract class ViewCommon extends ViewBase implements ViewDefinition {
         }
     }
 
+    public _onLivesync(context?: ModuleContext): boolean {
+        _rootModalViews.forEach(v => v.closeModal());
+        _rootModalViews.length = 0;
+
+        // Currently, we pass `context` only for style modules
+        if (context && context.path) {
+            return this.changeLocalStyles(context.path);
+        }
+
+        return false;
+    }
+
+    private changeLocalStyles(contextPath: string): boolean {
+        if (!this.changeStyles(this, contextPath)) {
+            eachDescendant(this, (child: ViewBase) => {
+                this.changeStyles(child, contextPath);
+                return true;
+            });
+        }
+        // Do not execute frame navigation for a change in styles
+        return true;
+    }
+
+    private changeStyles(view: ViewBase, contextPath: string): boolean {
+        if (view._moduleName && contextPath.includes(view._moduleName)) {
+            (<this>view).changeCssFile(contextPath);
+            return true;
+        }
+        return false;
+    }
+
     _setupAsRootView(context: any): void {
         super._setupAsRootView(context);
         if (!this._styleScope) {
@@ -210,12 +241,6 @@ export abstract class ViewCommon extends ViewBase implements ViewDefinition {
         }
     }
 
-    _onLivesync(): boolean {
-        _rootModalViews.forEach(v => v.closeModal());
-        _rootModalViews.length = 0;
-        return false;
-    }
-
     public onBackPressed(): boolean {
         return false;
     }

tns-core-modules/ui/frame/frame-common.ts

@@ -564,44 +564,34 @@ export class FrameBase extends CustomLayoutView implements FrameDefinition {
     }
 
     public _onLivesync(context?: ModuleContext): boolean {
-        super._onLivesync();
-
-        if (!this._currentEntry || !this._currentEntry.entry) {
-            return false;
-        }
-
-        const currentEntry = this._currentEntry.entry;
-        if (context && context.path) {
-            // Use topmost instead of this to cover nested frames scenario
-            const topmostFrame = topmost();
-            const moduleName = topmostFrame.currentEntry.moduleName;
-            const reapplyStyles = context.path.includes(moduleName);
-            if (reapplyStyles && moduleName) {
-                topmostFrame.currentPage.changeCssFile(context.path);
-                return true;
+        // Execute a navigation if not handled on `View` level
+        if (!super._onLivesync(context)) {
+            if (!this._currentEntry || !this._currentEntry.entry) {
+                return false;
             }
-        }
 
-        const newEntry: NavigationEntry = {
-            animated: false,
-            clearHistory: true,
-            context: currentEntry.context,
-            create: currentEntry.create,
-            moduleName: currentEntry.moduleName,
-            backstackVisible: currentEntry.backstackVisible
-        }
+            const currentEntry = this._currentEntry.entry;
+            const newEntry: NavigationEntry = {
+                animated: false,
+                clearHistory: true,
+                context: currentEntry.context,
+                create: currentEntry.create,
+                moduleName: currentEntry.moduleName,
+                backstackVisible: currentEntry.backstackVisible
+            }
 
-        // If create returns the same page instance we can't recreate it.
-        // Instead of navigation set activity content.
-        // This could happen if current page was set in XML as a Page instance.
-        if (newEntry.create) {
-            const page = newEntry.create();
-            if (page === this.currentPage) {
-                return false;
+            // If create returns the same page instance we can't recreate it.
+            // Instead of navigation set activity content.
+            // This could happen if current page was set in XML as a Page instance.
+            if (newEntry.create) {
+                const page = newEntry.create();
+                if (page === this.currentPage) {
+                    return false;
+                }
             }
-        }
 
-        this.navigate(newEntry);
+            this.navigate(newEntry);
+        }
         return true;
     }
 }