Update to Vue 3

[ryleyb]

I was aiming to get this working but it's not perfect. The build size increased and I don't have time to sort out why.

[DuyKhang2804]

Hi ryleB,

Thank you very much for the Vue 3 patch.
Could you package it into an npm package?

[map9]

I was aiming to get this working but it's not perfect. The build size increased and I don't have time to sort out why.

fixed some bugs:

tree-item.vue

•  @dragstart.stop="onItemDragStart($event, _self, _self.model)"
  

•  @dragend.stop.prevent="onItemDragEnd($event, _self, _self.model)"
  

•  @dragstart.stop="onItemDragStart($event, this, this.model)"
  

•  @dragend.stop.prevent="onItemDragEnd($event, this, this.model)" @dragover.stop.prevent="isDragEnter = true"
  

•    @drop.stop.prevent="handleItemDrop($event, _self, _self.model)">
  

•   @drop.stop.prevent="handleItemDrop($event, this, this.model)">
  

•                 if (this.$parent.$options._componentTag === 'tree-item') {
  

•                if (this.$parent && this.$parent.$options.name === 'TreeItem') {
  

tree.vue

•                                self.oriParent[i] = dataItem;
  

•                                oriParent[i] = dataItem;