TypeScript scrollable.Scrollable類代碼示例

	constructor(configuration: editorCommon.IConfiguration, lineCount: number, scheduleAtNextAnimationFrame: (callback: () => void) => IDisposable) {
		super();

		this._configuration = configuration;
		this._linesLayout = new LinesLayout(lineCount, this._configuration.editor.lineHeight);

		this.scrollable = this._register(new Scrollable(0, scheduleAtNextAnimationFrame));
		this._configureSmoothScrollDuration();

		this.scrollable.setScrollDimensions({
			width: configuration.editor.layoutInfo.contentWidth,
			height: configuration.editor.layoutInfo.contentHeight
		});
		this.onDidScroll = this.scrollable.onScroll;

		this._updateHeight();
	}

	public deltaScrollNow(deltaScrollLeft: number, deltaScrollTop: number): void {
		const currentScrollPosition = this.scrollable.getCurrentScrollPosition();
		this.scrollable.setScrollPositionNow({
			scrollLeft: currentScrollPosition.scrollLeft + deltaScrollLeft,
			scrollTop: currentScrollPosition.scrollTop + deltaScrollTop
		});
	}

	public getFutureViewport(): Viewport {
		const scrollDimensions = this.scrollable.getScrollDimensions();
		const currentScrollPosition = this.scrollable.getFutureScrollPosition();
		return new Viewport(
			currentScrollPosition.scrollTop,
			currentScrollPosition.scrollLeft,
			scrollDimensions.width,
			scrollDimensions.height
		);
	}

	private _setDesiredScrollPositionNow(_desiredScrollPosition: number): void {

		let desiredScrollPosition: INewScrollPosition = {};
		this.writeScrollPosition(desiredScrollPosition, _desiredScrollPosition);

		this._scrollable.setScrollPositionNow(desiredScrollPosition);
	}

	public onMaxLineWidthChanged(maxLineWidth: number): void {
		let newScrollWidth = this._computeScrollWidth(maxLineWidth, this.getCurrentViewport().width);
		this.scrollable.setScrollDimensions({
			scrollWidth: newScrollWidth
		});

		// The height might depend on the fact that there is a horizontal scrollbar or not
		this._updateHeight();
	}

	public getLinesViewportDataAtScrollTop(scrollTop: number): IPartialViewLinesViewportData {
		// do some minimal validations on scrollTop
		const scrollDimensions = this.scrollable.getScrollDimensions();
		if (scrollTop + scrollDimensions.height > scrollDimensions.scrollHeight) {
			scrollTop = scrollDimensions.scrollHeight - scrollDimensions.height;
		}
		if (scrollTop < 0) {
			scrollTop = 0;
		}
		return this._linesLayout.getLinesViewportData(scrollTop, scrollTop + scrollDimensions.height);
	}

	public saveState(): { scrollTop: number; scrollTopWithoutViewZones: number; scrollLeft: number; } {
		const currentScrollPosition = this.scrollable.getFutureScrollPosition();
		let scrollTop = currentScrollPosition.scrollTop;
		let firstLineNumberInViewport = this._linesLayout.getLineNumberAtOrAfterVerticalOffset(scrollTop);
		let whitespaceAboveFirstLine = this._linesLayout.getWhitespaceAccumulatedHeightBeforeLineNumber(firstLineNumberInViewport);
		return {
			scrollTop: scrollTop,
			scrollTopWithoutViewZones: scrollTop - whitespaceAboveFirstLine,
			scrollLeft: currentScrollPosition.scrollLeft
		};
	}

	private _getTotalHeight(): number {
		const scrollDimensions = this.scrollable.getScrollDimensions();

		let result = this._linesLayout.getLinesTotalHeight();
		if (this._configuration.editor.viewInfo.scrollBeyondLastLine) {
			result += scrollDimensions.height - this._configuration.editor.lineHeight;
		} else {
			result += this._getHorizontalScrollbarHeight(scrollDimensions);
		}

		return Math.max(scrollDimensions.height, result);
	}

		let onBrowserDesperateReveal = (domNode: HTMLElement, lookAtScrollTop: boolean, lookAtScrollLeft: boolean) => {
			const scrollState = this.scrollable.getState();
			let newScrollPosition: INewScrollPosition = {};

			if (lookAtScrollTop) {
				let deltaTop = domNode.scrollTop;
				if (deltaTop) {
					newScrollPosition.scrollTop = scrollState.scrollTop + deltaTop;
					domNode.scrollTop = 0;
				}
			}

			if (lookAtScrollLeft) {
				let deltaLeft = domNode.scrollLeft;
				if (deltaLeft) {
					newScrollPosition.scrollLeft = scrollState.scrollLeft + deltaLeft;
					domNode.scrollLeft = 0;
				}
			}

			this.scrollable.updateState(newScrollPosition);
		};

	public onConfigurationChanged(e: IConfigurationChangedEvent): void {
		if (e.lineHeight) {
			this._linesLayout.setLineHeight(this._configuration.editor.lineHeight);
		}
		if (e.layoutInfo) {
			this.scrollable.setScrollDimensions({
				width: this._configuration.editor.layoutInfo.contentWidth,
				height: this._configuration.editor.layoutInfo.contentHeight
			});
		}
		if (e.viewInfo) {
			this._configureSmoothScrollDuration();
		}
		this._updateHeight();
	}