TSYWXT-WX-APP/pages/index/tab/tab.js

const themes = {
  smallBar: 'smallBar'
}

Component({
  /**
   * 组件的属性列表
   */
  properties: {
    items: {
      type: Array,
      value: ['item1', 'item2', 'item3', 'item4'],
      observer: function (newVal) {
        if (newVal && newVal.length < 5) {
          this.setData({
            itemWidth: (750 / newVal.length) - 60
          })
        }
      }
    },
    height: {
      type: String,
      value: '120'
    },
    textColor: {
      type: String,
      value: '#666666'
    },
    textSize: {
      type: String,
      value: '28'
    },
    selectColor: {
      type: String,
      value: '#426666'
    },
    selected: {
      type: String,
      value: '0',
      observer: function (newVal) {
        this.setData({
          mSelected: newVal
        })
      }
    },
    theme: {
      type: String,
      value: 'default',
      observer: function (newVal) {
        if (this.data.theme == themes.smallBar) {
          this.setData({
            bottom: this.data.height / 2 - this.data.textSize - 8,
            scrollStyle: ''
          })
        }
      }
    },
    dataCus: {
      type: Array,
      value: '',
      observer: function (newVal) {
        this.setData({
          mDataCus: newVal
        });
      }
    }
  },

  /**
   * 组件的初始数据
   */
  data: {
    itemWidth: 128,
    isScroll: true,
    scrollStyle: 'border-bottom: 1px solid #e5e5e5;',
    left: '0',
    right: '750',
    bottom: '0',
    mSelected: '0',
    lastIndex: 0,
    transition: 'left 0.5s, right 0.2s',
    windowWidth: 375,
    domData: [],
    textDomData: [],
    mDataCus: [],
    theme:"default"
  },

  externalClasses: ['cus'],

  /**
   * 组件的方法列表
   */
  methods: {
    barLeft: function(index, dom) {
      let that = this;
      this.setData({
        left: dom[index].left
      })
    },
    barRight: function (index, dom) {
      let that = this;
      this.setData({
        right: that.data.windowWidth - dom[index].right,
      })
    },
    onItemTap: function(e) {
      const index = e.currentTarget.dataset.index;
      let str = this.data.lastIndex < index ? 'left 0.5s, right 0.2s' : 'left 0.2s, right 0.5s';
      this.setData({
        transition: str,
        lastIndex: index,
        mSelected: index
      })
      if (this.data.theme == themes.smallBar) {
        this.barLeft(index, this.data.textDomData);
        this.barRight(index, this.data.textDomData);
      } else {
        this.barLeft(index, this.data.domData);
        this.barRight(index, this.data.domData);
      }
      this.triggerEvent('itemtap', e, { bubbles: true });
    }
  },
  ready: function() { 
    let that = this;
    const sysInfo = wx.getSystemInfoSync();
    this.setData({
      windowWidth: sysInfo.screenWidth
    })
    const query = this.createSelectorQuery();
    query.in(this).selectAll('.item').fields({
      dataset: true,
      rect: true,
      size: true
    }, function (res) {
      that.setData({
        domData: res,
      })
      that.barLeft(that.data.mSelected, that.data.domData);
      that.barRight(that.data.mSelected, that.data.domData);
      // console.log(res)
    }).exec()
    query.in(this).selectAll('.text').fields({
      dataset: true,
      rect: true,
      size: true
    }, function (res) {
      that.setData({
        textDomData: res,
      })
      if (that.data.theme == themes.smallBar) {
        that.barLeft(that.data.mSelected, that.data.textDomData);
        that.barRight(that.data.mSelected, that.data.textDomData);
      }
      console.log(res)
    }).exec()
  },
  lifetimes: {
    ready: function () {
      let that = this;
      const sysInfo = wx.getSystemInfoSync();
      this.setData({
        windowWidth: sysInfo.screenWidth
      })
      const query = this.createSelectorQuery();
      query.in(this).selectAll('.item').fields({
        dataset: true,
        rect: true,
        size: true
      }, function (res) {
        that.setData({
          domData: res,
        })
        that.barLeft(that.data.mSelected, that.data.domData);
        that.barRight(that.data.mSelected, that.data.domData);
        // console.log(res)
      }).exec()
      query.in(this).selectAll('.text').fields({
        dataset: true,
        rect: true,
        size: true
      }, function (res) {
        that.setData({
          textDomData: res,
        })
        if (that.data.theme == themes.smallBar) {
          that.barLeft(that.data.mSelected, that.data.textDomData);
          that.barRight(that.data.mSelected, that.data.textDomData);
        }
        console.log(res)
      }).exec()
    },
  },
})