@tarojs/components/dist/esm/taro-picker-view-column-core.entry.js

Taro 组件库。

import { r as registerInstance, c as createEvent, h, g as getElement, H as Host } from './index-5bd7cbab.js';
import { d as debounce } from './index-cad8203e.js';

const columnCss = ".taro-picker-view-column-container{display:-ms-flexbox;display:flex;overflow:scroll;overflow-x:hidden;position:relative;-ms-flex-direction:column;flex-direction:column;-ms-flex:1;flex:1;text-align:center}.taro-picker-view-column-container::-webkit-scrollbar{display:none}";

let PickerViewColumn = class {
  constructor(hostRef) {
    registerInstance(this, hostRef);
    this.onChange = createEvent(this, "onselect", 7);
    this.onSelectStart = createEvent(this, "onselectstart", 7);
    this.onSelectEnd = createEvent(this, "onselectend", 7);
    // 初始化的选中位置
    this.initialPosition = '0';
    // 滑动距离上下留白区域-通过父视图和 indicator 计算而来
    this.paddingVertical = 0;
    this.isInit = false;
    this.isMove = false;
    // 滚动结束自动回到合适的位置
    this.handleSelected = debounce(() => {
      const childList = this.el.childNodes;
      let sum = 0;
      let selectedIndex = '0';
      for (const index in childList) {
        const item = childList[index];
        const itemHeight = item.offsetHeight;
        if (sum + itemHeight / 2.0 > this.el.scrollTop) {
          selectedIndex = index;
          break;
        }
        sum += itemHeight;
      }
      this.el.scrollTo({
        top: sum,
        behavior: 'smooth'
      });
      this.onChange.emit({
        curIndex: this.col,
        selectedIndex: selectedIndex
      });
      this.onSelectEnd.emit();
    }, 500);
  }
  onScroll(_event) {
    if (!this.isMove) {
      this.isMove = true;
      this.onSelectStart.emit();
    }
    this.handleSelected();
  }
  onMouseEnd() {
    if (!this.isMove)
      return;
    this.isMove = false;
    this.handleSelected();
  }
  onTouchEnd() {
    this.isMove = false;
    this.handleSelected();
  }
  componentDidUpdate() {
    if (!this.isInit) {
      this.isInit = true;
      const childList = this.el.childNodes;
      let idx = 0;
      let sum = 0;
      for (const index in childList) {
        const item = childList[index];
        if (this.initialPosition === index || !item || typeof item.offsetHeight !== 'number') {
          break;
        }
        sum += item.offsetHeight;
        idx++;
      }
      this.el.scrollTo({ top: sum });
      if (idx >= childList.length) {
        this.onChange.emit({
          curIndex: this.col,
          selectedIndex: idx - 1
        });
      }
    }
  }
  render() {
    const { paddingVertical = 0 } = this;
    return (h(Host, { class: "taro-picker-view-column-container", style: { 'padding-top': `${paddingVertical}px`, 'padding-bottom': `${paddingVertical}px` } }));
  }
  get el() { return getElement(this); }
};
PickerViewColumn.style = columnCss;

export { PickerViewColumn as taro_picker_view_column_core };