E_WeChat/components/Yl_FloatingButton/index.js

Component({
  properties: {
      radius: {
          type: Number
      }, //半径 单位px
      useSlot: {
          type: Boolean
      },
      zIndex: {
          type: Number,
          value: 99
      }
  },
  data: {
      top: "550px",
      left: "345px",
      viewHeight: null,
      alternative: false,
      viewWidth: 375
  },
  lifetimes: {
      attached: function () {
          this.setData({
              userid: wx.getStorageSync('userMsg').userid
          })
          let that = this;
          wx.getSystemInfo({
              success: (res => that.setData({
                  viewHeight: res.windowHeight,
                  viewWidth: res.windowWidth // ✅ 加这一行
              }))
          });
      },
  },
  methods: {
      viewTouchMove(e) {
          let left = e.touches[0].pageX;
          if (left > (this.data.viewWidth - this.data.radius)) left = this.data.viewWidth - (this.data.radius / 2);
          if (left < 0 + this.data.radius) left = 0 + this.data.radius;
          let top = e.touches[0].pageY;
          if (top < 0 + this.data.radius) top = 0 + this.data.radius;
          if (top > this.data.viewHeight - this.data.radius) top = this.data.viewHeight - this.data.radius;
          this.setData({
              left: left + 'px',
              top: top + 'px'
          })
      },
      imageOnErr(e) {
          console.log("图片加载失败")
          this.setData({
              alternative: true
          })
      }
  }
})