uniapp下拉菜单四级菜单

根据提供的引用内容，uniapp没有提供直接实现四级下拉菜单的组件，但可以通过嵌套使用uni.showActionSheet()方法来实现类似的效果。具体实现方法如下：

// 定义四级菜单的数据
let menuData = [
  {
    name: '一级菜单1',
    subMenu: [
      {
        name: '二级菜单1-1',
        subMenu: [
          {
            name: '三级菜单1-1-1',
            subMenu: [
              {
                name: '四级菜单1-1-1-1'
              },
              {
                name: '四级菜单1-1-1-2'
              }
            ]
          },
          {
            name: '三级菜单1-1-2',
            subMenu: [
              {
                name: '四级菜单1-1-2-1'
              },
              {
                name: '四级菜单1-1-2-2'
              }
            ]
          }
        ]
      },
      {
        name: '二级菜单1-2',
        subMenu: [
          {
            name: '三级菜单1-2-1',
            subMenu: [
              {
                name: '四级菜单1-2-1-1'
              },
              {
                name: '四级菜单1-2-1-2'
              }
            ]
          },
          {
            name: '三级菜单1-2-2',
            subMenu: [
              {
                name: '四级菜单1-2-2-1'
              },
              {
                name: '四级菜单1-2-2-2'
              }
            ]
          }
        ]
      }
    ]
  },
  {
    name: '一级菜单2',
    subMenu: [
      {
        name: '二级菜单2-1',
        subMenu: [
          {
            name: '三级菜单2-1-1',
            subMenu: [
              {
                name: '四级菜单2-1-1-1'
              },
              {
                name: '四级菜单2-1-1-2'
              }
            ]
          },
          {
            name: '三级菜单2-1-2',
            subMenu: [
              {
                name: '四级菜单2-1-2-1'
              },
              {
                name: '四级菜单2-1-2-2'
              }
            ]
          }
        ]
      },
      {
        name: '二级菜单2-2',
        subMenu: [
          {
            name: '三级菜单2-2-1',
            subMenu: [
              {
                name: '四级菜单2-2-1-1'
              },
              {
                name: '四级菜单2-2-1-2'
              }
            ]
          },
          {
            name: '三级菜单2-2-2',
            subMenu: [
              {
                name: '四级菜单2-2-2-1'
              },
              {
                name: '四级菜单2-2-2-2'
              }
            ]
          }
        ]
      }
    ]
  }
]

// 定义四级菜单的显示方法
function showMenu(menuData) {
  let itemList = []
  let subMenu = menuData.subMenu
  for (let i = 0; i < subMenu.length; i++) {
    itemList.push(subMenu[i].name)
  }
  uni.showActionSheet({
    itemList: itemList,
    success: function(res) {
      let tapIndex = res.tapIndex
      if (tapIndex >= 0 && tapIndex < subMenu.length) {
        let selectedMenu = subMenu[tapIndex]
        if (selectedMenu.subMenu && selectedMenu.subMenu.length > 0) {
          showMenu(selectedMenu)
        } else {
          console.log(selectedMenu.name)
        }
      }
    },
    fail: function(res) {
      console.log(res.errMsg)
    }
  })
}

// 调用四级菜单的显示方法
showMenu({
  subMenu: menuData
})