gojs一些实用的高级用法

// 后面所用到的 diagram 都是 Gojs 创建的实例
// diagram_container 为图容器dom id
diagram = $(go.Diagram, 'diagram_container') 

function updateData (nodeArr = [], linkArr = [], hasAnimation = true ) {
  if (hasAnimation) {
    diagram.model = new go.GraphLinksModel(nodeArr, linkArr);
  } else {
    diagram.model.nodeDataArray = nodeArr
    diagram.model.linkDataArray = linkArr
  }
}

// 初始化实例后处理，只用一次
diagram.animationManager.canStart = function(reason) {
  if (reason === 'Model') return false
  return true
}

// 绑定数据至 diagram，绘制图
function updateData (nodeArr = [], linkArr = [], hasAnimation = true ) {
  if (hasAnimation) {
    diagram.model = new go.GraphLinksModel(nodeArr, linkArr);
  } else {
    diagram.model.nodeDataArray = nodeArr
    diagram.model.linkDataArray = linkArr
    diagram.animationManager.stopAnimation()
  }
}

// 绑定数据至 diagram，绘制图
function updateData (nodeArr = [], linkArr = [], hasAnimation = true) {
  diagram.model = new go.GraphLinksModel(nodeArr, linkArr);
  if (diagram.animationManager) {
    // Default 有动画，None 没有动画
    diagram.animationManager.initialAnimationStyle = hasAnimation ? go.AnimationManager.Default : go.AnimationManager.None;
  }
}

function downloadImg = ({
  imgName = 'dag',
  bGColor = 'white',
  imgType = 'image/png'
}= {}) {
  diagram.makeImageData({
    scale: 2,
    padding: new go.Margin(50, 70),
    maxSize: new go.Size(Infinity, Infinity),
    background: bgColor,
    type: imgType,
    returnType: 'blob',
    callback: (blob: any) => {
      const url = window.URL.createObjectURL(blob)
      const fileName = imgName + '.png'
      const aEl = document.createElement('a')
      aEl.style.display = 'none'
      aEl.href = url
      aEl.download = fileName

      // IE 11
      if (window.navigator.msSaveBlob !== undefined) {
        window.navigator.msSaveBlob(blob, fileName)
        return
      }

      document.body.appendChild(aEl)
      requestAnimationFrame(function() {
        aEl.click()
        window.URL.revokeObjectURL(url)
        document.body.removeChild(aEl)
      })
    }
  })
}

// 禁用 ctl 相关操作
diagram.commandHandler.doKeyDown = function() {
  const e = diagram.lastInput
  const control = e.control || e.meta
  const key = e.key

  // 取消 Ctrl+A/Z/Y/G  A-全选、Z-撤销、Y-重做、G-分组
  if (control && ['A', 'Z', 'Y', 'G'].includes(key)) return
  // 取消 Del/Backspace 删除键
  if (key === 'Del' || key === 'Backspace') return

  go.CommandHandler.prototype.doKeyDown.call(this)
}

function infiniteScroll = (infiniteScroll) {
  this.diagram.scrollMode = infiniteScroll ? go.Diagram.InfiniteScroll : go.Diagram.DocumentScroll
}

// groupIds 为所有 group 的ids，从外到内。 一开始遍历组装数据的时候就收集好
// groupIdsReverse 为所有 group 的ids，从内到外
// 全部展开，从外到内
// 全部收起，从内到外
function setExpandCollapse (isExpand, groupIds, groupIdsReverse) {
  // 展开和折叠需要从两个方向处理，再次展开折叠交互才正常，否则第一次点无效，需要点第二次材有限
  let arr = isExpand ? groupIds : groupIdsReverse;
  let group;

  arr.forEach(id => {
    group = diagram.findNodeForKey(id);
    group.isSubGraphExpanded = isExpand;
  })
},

function setExpandCollapse (isExpand) {
  const { nodeDataArray, linkDataArray } = diagram.model
  const newNodeArr = nodeDataArray.map(v => {
    if (v.isGroup) {
      return {...v, isExpanded: isExpand}
    }
    return v
  })

  // 上面的方法
  updateData(newNodeArr, linkArr, false)
}

function loop = () {
  const animationTimer = setTimeout(() => {
    clearTimeout(animationTimer)
    const oldskips = diagram.skipsUndoManager;
    diagram.skipsUndoManager = true;

    // 虚线动画
    diagram.links.each((link: any) => {
      const dashedLinkShape = link.findObject("dashedLink");
      if (dashedLinkShape) {
        const off = dashedLinkShape.strokeDashOffset - 3;
        // 设置（移动）笔划划动画
        dashedLinkShape.strokeDashOffset = (off <= 0) ? 60 : off;
      }
    });

    // loading 旋转
    diagram.nodes.each((node: any) => {
      const loadingShape = node.findObject("loading");
      if (loadingShape) {
        const angle = loadingShape.angle + 20;
        // 设置（移动）笔划划动画
        loadingShape.angle = (angle == 0) ? 360 : angle;
      }
    });

    diagram.skipsUndoManager = oldskips;
    loop();
  }, 180);
}
loop()

diagram.toolManager.dragSelectingTool.box = $(go.Part,
  { layerName: "Tool", selectable: false },
  $(go.Shape,
    { name: "SHAPE", fill: 'rgba(104, 129, 255, 0.2)', stroke: 'rgba(104, 129, 255, 0.5)', strokeWidth: 2 }));