fix(throttle): fix issue of long time to fire event

.gitignore

@@ -60,4 +60,5 @@ $ cat .gitignore
 *.tgz
 
 npm-debug.*
-examples/ 
+examples/ 
+package-lock.json

CHANGELOG.md

@@ -1,3 +1,7 @@
+## v 0.8.3 (2018/02/21)
+* [FIX] - fix for #198 - takes a long time for onscroll to fire 
+* [UPDATE] - default value for throttle changed to 150  
+
 ## v 0.8.2 (2018/01/07)
 * [FIX] - fix for #221 - action not fired on Windows scrolling
 * [FIX] - fix for #228 - scrolling back up to the top of the list and then scroll down doesn't trigger event 

README.md

@@ -25,7 +25,7 @@ Currently supported attributes:
 * **infiniteScrollDistance**<_number_> - (optional, default: **2**) - the bottom percentage point of the scroll nob relatively to the infinite-scroll container (i.e, 2 (2 * 10 = 20%) is event is triggered when 80% (100% - 20%) has been scrolled).  
 if container.height is 900px, when the container is scrolled to or past the 720px, it will fire the scrolled event. 
 * **infiniteScrollUpDistance**<_number_> - (optional, default: **1.5**) - should get a number
-* **infiniteScrollThrottle**<_number_> - (optional, default: **300**) - should get a number of **milliseconds** for throttle. The event will be triggered this many milliseconds after the user *stops* scrolling.
+* **infiniteScrollThrottle**<_number_> - (optional, default: **150**) - should get a number of **milliseconds** for throttle. The event will be triggered this many milliseconds after the user *stops* scrolling.
 * **infiniteScrollContainer**<_string|HTMLElement_> - (optional, default: null) - should get a html element or css selector for a scrollable element; window or current element will be used if this attribute is empty.
 * **scrolled**<_function_> - this will callback if the distance threshold has been reached on a scroll down.
 * **scrolledUp**<_function_> - (event: InfiniteScrollEvent) - this will callback if the distance threshold has been reached on a scroll up.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "ngx-infinite-scroll",
-  "version": "0.8.2",
+  "version": "0.8.3",
   "description": "An infinite scroll directive for Angular compatible with AoT compilation and Tree shaking",
   "main": "./bundles/ngx-infinite-scroll.umd.js",
   "module": "./modules/ngx-infinite-scroll.es5.js",
@@ -61,7 +61,7 @@
     "karma-webpack": "2.0.3",
     "reflect-metadata": "0.1.10",
     "rollup": "0.41.6",
-    "rxjs": "5.2.0",
+    "rxjs": "5.5.2",
     "ts-helpers": "1.1.2",
     "ts-loader": "2.0.3",
     "tslint": "4.5.1",

src/modules/infinite-scroll.directive.ts

@@ -26,7 +26,7 @@ export class InfiniteScrollDirective
 
   @Input() infiniteScrollDistance: number = 2;
   @Input() infiniteScrollUpDistance: number = 1.5;
-  @Input() infiniteScrollThrottle: number = 300;
+  @Input() infiniteScrollThrottle: number = 150;
   @Input() infiniteScrollDisabled: boolean = false;
   @Input() infiniteScrollContainer: any = null;
   @Input() scrollWindow: boolean = true;

tests/services/scroll-register.spec.ts

@@ -24,22 +24,51 @@ describe('Scroll Regsiter', () => {
     return { element: mockedElement, container: mockedContainer };
   };
 
-  // beforeEach(() => {
-
-  // });
-
   it('should create a Observable of scroll observable', () => {
     const mockDom = createMockDom();
     const scrollConfig: Models.IScrollRegisterConfig = {
       container: mockDom.container.nativeElement,
       throttle: 300,
-
     };
     const scroller$: Observable<{}> = ScrollRegister.attachScrollEvent(scrollConfig);
     const actual = scroller$;
     expect(actual).toBeDefined();
   });
 
+  [
+    {
+      it: 'should create a Observable of scroll observable with default 300 throttle',
+      config: {
+        throttle: 300,
+      },
+      expected: 300
+    },
+    {
+      it: 'should create a Observable of scroll observable without a sampleTime if throttle is 0',
+      config: {
+        throttle: 0
+      },
+      expected: 0
+    }
+  ].forEach((spec) => {
+    it(spec.it, (done) => {
+      const mockDom = createMockDom();
+      const scrollConfig: Models.IScrollRegisterConfig = {
+        container: mockDom.container.nativeElement,
+        ...spec.config
+      };
+      const scroller$: Observable<{}> = ScrollRegister.attachScrollEvent(scrollConfig);
+      const start = new Date();
+      scroller$.subscribe((result) => {
+        const end = new Date();
+        const actual = end.getTime() - start.getTime();
+        expect(actual).toBeGreaterThanOrEqual(spec.expected);
+        done();
+      });
+      mockDom.container.nativeElement.dispatchEvent(new Event('scroll'));
+    });
+  });
+
   it('should create a scroll params object', () => {
     const lastScrollPosition = 0;
     const positionStats = {} as Models.IPositionStats;