TypeScript scroll-spy.service.ScrollSpiedElementGroup类代码示例

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本文整理汇总了TypeScript中app/shared/scroll-spy.service.ScrollSpiedElementGroup类的典型用法代码示例。如果您正苦于以下问题：TypeScript service.ScrollSpiedElementGroup类的具体用法？TypeScript service.ScrollSpiedElementGroup怎么用？TypeScript service.ScrollSpiedElementGroup使用的例子？那么恭喜您, 这里精选的类代码示例或许可以为您提供帮助。

在下文中一共展示了service.ScrollSpiedElementGroup类的3个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于我们的系统推荐出更棒的TypeScript代码示例。

示例1: beforeEach

    beforeEach(() => {
      const tops = [50, 150, 100];

      spyOn(ScrollSpiedElement.prototype, 'calculateTop').and.callFake(function(scrollTop, topOffset) {
        this.top = tops[this.index];
      });

      activeItems = [];
      group = new ScrollSpiedElementGroup([{}, {}, {}] as Element[]);
      group.activeScrollItem.subscribe(item => activeItems.push(item));
      group.calibrate(20, 10);
    });

开发者ID:DanielKucal，项目名称:angular，代码行数:12，代码来源:scroll-spy.service.spec.ts

示例2: describe

  describe('#onScroll()', () => {
    let group: ScrollSpiedElementGroup;
    let activeItems: (ScrollItem|null)[];

    const activeIndices = () => activeItems.map(x => x && x.index);

    beforeEach(() => {
      const tops = [50, 150, 100];

      spyOn(ScrollSpiedElement.prototype, 'calculateTop').and.callFake(
        function(this: ScrollSpiedElement, scrollTop: number, topOffset: number) {
        this.top = tops[this.index];
      });

      activeItems = [];
      group = new ScrollSpiedElementGroup([{}, {}, {}] as Element[]);
      group.activeScrollItem.subscribe(item => activeItems.push(item));
      group.calibrate(20, 10);
    });


    it('should emit a `ScrollItem` on `activeScrollItem`', () => {
      expect(activeItems.length).toBe(0);

      group.onScroll(20, 140);
      expect(activeItems.length).toBe(1);

      group.onScroll(20, 140);
      expect(activeItems.length).toBe(2);
    });

    it('should emit the lower-most element that is above `scrollTop`', () => {
      group.onScroll(45, 200);
      group.onScroll(55, 200);
      expect(activeIndices()).toEqual([null, 0]);

      activeItems.length = 0;
      group.onScroll(95, 200);
      group.onScroll(105, 200);
      expect(activeIndices()).toEqual([0, 2]);

      activeItems.length = 0;
      group.onScroll(145, 200);
      group.onScroll(155, 200);
      expect(activeIndices()).toEqual([2, 1]);

      activeItems.length = 0;
      group.onScroll(75, 200);
      group.onScroll(175, 200);
      group.onScroll(125, 200);
      group.onScroll(25, 200);
      expect(activeIndices()).toEqual([0, 1, 2, null]);
    });

    it('should always emit the lower-most element if scrolled to the bottom', () => {
      group.onScroll(140, 140);
      group.onScroll(145, 140);
      group.onScroll(138.5, 140);
      group.onScroll(139.5, 140);

      expect(activeIndices()).toEqual([1, 1, 2, 1]);
    });

    it('should emit null if all elements are below `scrollTop`', () => {
      group.onScroll(0, 140);
      expect(activeItems).toEqual([null]);

      group.onScroll(49, 140);
      expect(activeItems).toEqual([null, null]);
    });

    it('should emit null if there are no spied elements (even if scrolled to the bottom)', () => {
      group = new ScrollSpiedElementGroup([]);
      group.activeScrollItem.subscribe(item => activeItems.push(item));

      group.onScroll(20, 140);
      expect(activeItems).toEqual([null]);

      group.onScroll(140, 140);
      expect(activeItems).toEqual([null, null]);

      group.onScroll(145, 140);
      expect(activeItems).toEqual([null, null, null]);
    });
  });

开发者ID:DallanQ，项目名称:rxjs，代码行数:85，代码来源:scroll-spy.service.spec.ts

示例3: it

    it('should emit null if all elements are below `scrollTop`', () => {
      group.onScroll(0, 140);
      expect(activeItems).toEqual([null]);

      group.onScroll(49, 140);
      expect(activeItems).toEqual([null, null]);
    });

开发者ID:DallanQ，项目名称:rxjs，代码行数:7，代码来源:scroll-spy.service.spec.ts

注：本文中的app/shared/scroll-spy.service.ScrollSpiedElementGroup类示例由纯净天空整理自Github/MSDocs等源码及文档管理平台，相关代码片段筛选自各路编程大神贡献的开源项目，源码版权归原作者所有，传播和使用请参考对应项目的License；未经允许，请勿转载。