vue项目中使用bpmn-流程图预览篇

<template>
    <div class="container">
        <el-button type="primary" @click="previewTemp">预览</el-button>
        <el-button type="success" @click="handleZoom(1)">放大</el-button>
        <el-button type="warning" @click="handleZoom(-1)">缩小</el-button>
        <div class="chart-preview">
            <div style="clear: both;"></div>
            <div class="view-canvas">
                <div id="container"
                     v-bind:style="{width: 100 * scale + '%',height: 100 * scale + '%'}"
                ></div>
            </div>
        </div>
    </div>
</template>
<script>
  import jquery from 'jquery';
  import BpmnViewer from 'bpmn-js/lib/Viewer';


  export default {
    data() {
      return {
        containerEl: null,
        bpmnModeler: null,
        scale: 1,
       // 此变量为预览的xml文件数据，由于行数过多，附在了附件中，使用时，将附件整个复值到currentCanvasXml即可
        currentCanvasXml: ''
      };
    },
    methods: {
      handleZoom(flag) {
        if (flag < 0 && this.scale <= 1) {
          return;
        }
        this.scale += flag;
        this.$nextTick(() => {
          this.bpmnModeler.get('canvas').zoom('fit-viewport');
        });
      },
      previewTemp() {
        this.containerEl = document.getElementById('container');
        // 避免缓存，每次清一下
        this.bpmnModeler && this.bpmnModeler.destroy();
        this.scale = 1;
        this.bpmnModeler = new BpmnViewer({container: this.containerEl});
        const viewer = this.bpmnModeler;
        this.bpmnModeler.importXML(this.currentCanvasXml, (err) => {
          if (err) {
            console.error(err);
          } else {
            // 只实现预览，核心代码以下两句足够 
            const canvas = viewer.get('canvas');
            canvas.zoom('fit-viewport');
            // 以下代码为：为节点注册鼠标悬浮事件
            const eventBus = this.bpmnModeler.get('eventBus');
            const overlays = this.bpmnModeler.get('overlays');
            eventBus.on('element.hover', (e) => {
              const $overlayHtml = jquery(` <div class="tipBox">
                    你好，我是悬浮框里的内容
                    </div>`);
              overlays.add(e.element.id, {
                position: {top: e.element.height, left: 0},
                html: $overlayHtml
              });
            });
            eventBus.on('element.out', () => {
              overlays.clear();
            });
          //  注册悬浮事件结束
          }
        });
      }
    }
  };
</script>
<style lang="scss">
    .container {
        .tipBox {
            width: 200px;
            background: #fff;
            border-radius: 4px;
            border: 1px solid #ebeef5;
            padding: 12px;
        }
    }
</style>