js页面引导页的实现思路总结

  const stepData = [{
    title: '组件库和图标',
    content: '从基础组件、自定义业务组件、图标库中拖拽组件或图标到画布区域进行页面编排组装',
    target: '#editPageLeftSideBar',
    entry: () => void,
    leave: () => void
  }]

    const clearCls = () => {
        document.body.querySelectorAll('.guide-highlight').forEach(el => {
          el.classList.remove('guide-highlight')
        })
     }

    const addCls = (target) => {
       target.classList.add('guide-highlight');
    }

    const getTarget = () => {
        const currentStep = props.stepData[state.currentStepIndex]
        return document.querySelector(currentStep.target)
    }
    
    const onGoNext = () => {
        // 清除所有的高亮class, 因为我是通过class样式来控制的
        clearCls()

        // 查找下一步的目标对象
        const currentStep = props.stepData[state.currentStepIndex]
        const $stepTarget = getTarget()

        // 给target添加class
        addCls()

        // 执行其它方法，譬如上面的leave/entry方法
        if (typeof state.currentStep.leave === 'function') {
          state.currentStep.leave()
        }
        if (typeof currentStep.entry === 'function') {
          currentStep.entry()
        }

        // 计算引导容器的位置style

        const windowWidth = window.innerWidth
        const windowHieght = window.innerHeight
         const {
          top: targetTop,
          right: targetRight,
          bottom: targeBottom,
          left: targetLeft,
          width: targetWidth
        } = $stepTarget.getBoundingClientRect()
        const {
          width,
          height
        } = tipRef.value.getBoundingClientRect()
        let placement = 'left'
        if (width > height
          && targeBottom < 0.3 * windowHieght) {
          placement = targeBottom > 0.5 * windowHieght ? 'top' : 'bottom'
        } else {
          placement = targetLeft > 0.5 * windowWidth ? 'left' : 'right'
        }

        let styles = {}

        if (placement === 'bottom') {
          styles = {
            top: `${targeBottom + 10}px`,
            left: `${targetLeft + (targetWidth - width) / 2}px`
          }
        } else if (placement === 'top') {
          styles = {
            top: `${windowHieght - targetTop - height - 10}px`,
            left: `${targetLeft + (targetWidth - width) / 2}px`
          }
        } else if (placement === 'left') {
          styles = {
            top: `${targetTop}px`,
            right: `${windowWidth - targetLeft + 10}px`
          }
        } else if (placement === 'right') {
          styles = {
            top: `${targetTop}px`,
            left: `${targetRight + 10}px`
          }
        }
    }