@z-cloud/virtual-mini/dist/esm/index.js

提供Taro，uni-app的虚拟列表公共类

var __defProp = Object.defineProperty;
var __defNormalProp = (obj, key, value) => key in obj ? __defProp(obj, key, { enumerable: true, configurable: true, writable: true, value }) : obj[key] = value;
var __publicField = (obj, key, value) => __defNormalProp(obj, typeof key !== "symbol" ? key + "" : key, value);
import { BasicVirtualizer, debounce } from "@z-cloud/virtual-vanilla";
class MiniVirtualizer extends BasicVirtualizer {
  constructor(options) {
    super();
    __publicField(this, "scrollToIndexTimeoutId", null);
    __publicField(this, "resetScrolling", debounce(() => {
      this.scrolling = false;
      this.notify();
    }, 160));
    this.setOptions(options);
  }
  init() {
    this.scrollToOffset(
      typeof this.options.initialOffset === "function" ? this.options.initialOffset() : this.options.initialOffset
    );
    this.notify();
  }
  onElementSizeChange(index, rect) {
    const item = this.items[index];
    const size = rect[this.options.horizontal ? "width" : "height"];
    if (!item) {
      return;
    }
    const delta = size - item.size;
    if (Math.abs(delta) >= 1) {
      const offset = this.getScrollOffset();
      if (item.start < offset) {
        this.scrollTo(offset + delta);
      }
      this.dynamicSizeCache.set(index, size);
      this.pendingDynamicSizeIndexes.push(index);
      this.scrolling = false;
      this.clearFnMemo(["geItemsWithtMemo", "notifyWithMemo"]);
      this.notify();
    }
  }
  onScroll(res) {
    if (!res) {
      return;
    }
    const offset = res[this.options.horizontal ? "scrollLeft" : "scrollTop"] ?? 0;
    if (typeof this.scrollOffset !== "undefined" && Math.abs(this.scrollOffset - offset) < 5) {
      this.scrollOffset = offset;
      return;
    }
    this.scrollOffset = offset;
    this.scrolling = true;
    this.resetScrolling({ clearTimeout, setTimeout });
    this.notify();
  }
  scrollTo(_offset, _behavior = "instant") {
    console.warn("scrollTo 需要针对 uni-app 或者 taro 各自实现");
  }
  scrollToOffset(offset, behavior) {
    this.cancelScrollToIndex();
    this.scrollTo(offset, behavior);
  }
  cancelScrollToIndex() {
    if (this.scrollToIndexTimeoutId !== null) {
      clearTimeout(this.scrollToIndexTimeoutId);
      this.scrollToIndexTimeoutId = null;
    }
  }
  scrollToIndex(index, { align, behavior } = {}) {
    this.cancelScrollToIndex();
    const safeIndex = Math.max(0, Math.min(index, this.options.count - 1));
    const offset = this.getOffsetForIndex(safeIndex, align);
    if (!offset) {
      return;
    }
    this.scrollTo(offset, this.dynamicMode() ? "instant" : behavior);
    if (this.dynamicMode()) {
      this.scrollToIndexTimeoutId = setTimeout(() => {
        this.scrollToIndexTimeoutId = null;
        if (this.dynamicSizeCache.has(safeIndex)) {
          const calcOffset = this.getOffsetForIndex(safeIndex, align);
          if (!calcOffset) {
            return;
          }
          const currentScrollOffset = this.getScrollOffset();
          if (Math.abs(calcOffset - currentScrollOffset) > 1) {
            this.scrollToIndex(safeIndex, { align, behavior: "instant" });
          }
        } else {
          this.scrollToIndex(safeIndex, { align, behavior: "instant" });
        }
      });
    }
  }
  clean() {
    this.unsubscribes = this.unsubscribes.filter((unsub) => {
      if (typeof unsub === "function") {
        unsub();
      }
      return false;
    });
    this.dynamicSizeCache.clear();
    this.pendingDynamicSizeIndexes = [];
  }
}
export {
  MiniVirtualizer
};