背景：
由于项目的需要，当用户在查看流程图时，当点击某个流程图片上的节点时，需要提示一些信息，这就需要获取各个节点的信息，此处获取id和name的值。
注意：这个并不是流程图的高亮,即当点击网点申请环节时，获取该节点的id和name,即B001和网点申请，点击部门申请时，获取B002和部门经理审批
解释说明：
1.下方说的x和y:
2.流程定义的key: 即为下方id的值
3.节点的id和name的值：
难点分析：
由 于activiti在部署时，如果没有流程图片，则activiti会自动生成一张图片，而我们项目中使用的是activiti modeler实现的在线画流程图，部署时没有图片，是由activiti自动生成。而activiti在生成图片时，会对图片做一个裁剪操作，所有最终 各个节点的坐标会比实际的要小。
（即：activiti自动生成的图片，会做一个裁剪操作，各个节点实际的x和y的值比xml文件中的要小）
而我们的难点在于，各个节点实际坐标的获取。如下图所示：
即我们实际上获取的坐标需要在减去一个minX和minY，得到的才是我们的各个节点实际的坐标。
步骤分析：
1.根据流程定义的key,重新生成流程图片，而不是获取流程图片。
2.还是根据流程定义的key,获取各个节点的信息。（此处需要注意的是各个节点实际的x和y的值的获取的方法）
3.在jsp页面上使用绝对定位，给点击的节点加上高亮。
步骤实现： 1.根据流程定义的key,重新生成流程图片，而不是获取流程图片。
此处重新生成图片的原因：
因为有些时候我们在部署流程时，将图片也部署进去了，此时使用的就是自己的图片，activiti不会进行图片的裁剪。因为我在下一步获取流程节点的信息时，对x和y的进行了特殊处理，因此此处需要重新生成 流程图片。
/**InputStream is = ProcessDiagramGenerator.generatePngDiagram(bm); // 生成图片，获取图片的输入流
* 根据流程的key生成图片
*
* @param request
* @param response
* @param wfKey 流程定义的key
*/
@RequestMapping("/genericImageByWfKey")
public void genericImageByWfKey(HttpServletRequest request, HttpServletResponse response, String wfKey) {
Context.setProcessEngineConfiguration(processEngineConfiguration);
RepositoryService repositoryService = this.processEngine.getRepositoryService();
ProcessDefinition pd = repositoryService.createProcessDefinitionQuery().processDefinitionKey(wfKey).latestVersion().singleResult();
BpmnModel bm = repositoryService.getBpmnModel(pd.getId());
InputStream is = ProcessDiagramGenerator.generatePngDiagram(bm); // 生成图片，获取图片的输入流
try {
int size = is.available();
byte data[] = new byte[size];
is.read(data);
response.setContentType("image/png"); // 设置返回的文件类型
OutputStream os = response.getOutputStream();
os.write(data);
os.flush();
os.close();
} catch (IOException e) {
log.error("读写流程图时出现异常！");
}
log.info("end....");
}
try {
int size = is.available();
byte data[] = new byte[size];
is.read(data);
response.setContentType("image/png"); // 设置返回的文件类型
OutputStream os = response.getOutputStream();
os.write(data);
os.flush();
os.close();
} catch (IOException e) {
log.error("读写流程图时出现异常！");
}
log.info("end....");
}
2.还是根据流程定义的key,获取各个节点的信息。
获取各个节点的坐标之前，我们先看一下activiti中是如果获取到最小的x和y的，然后是如何裁剪图片的
2.1获取节点包括线的最小x和最小y :
跟踪acticiti的源码可以发现，最小x和y的获取（org.activiti.engine.impl.bpmn.diagram.ProcessDiagramGenerator.initProcessDiagramCanvas(BpmnModel)）
protected static ProcessDiagramCanvas initProcessDiagramCanvas(BpmnModel bpmnModel) {new ProcessDiagramCanvas((int) maxX + 10,(int) maxY + 10, (int) minX, (int) minY);
// We need to calculate maximum values to know how big the image will be in its entirety
double minX = Double.MAX_VALUE;
double maxX = 0;
double minY = Double.MAX_VALUE;
double maxY = 0; for (Pool pool : bpmnModel.getPools()) {
GraphicInfo graphicInfo = bpmnModel.getGraphicInfo(pool.getId());
minX = graphicInfo.getX();
maxX = graphicInfo.getX() + graphicInfo.getWidth();
minY = graphicInfo.getY();
maxY = graphicInfo.getY() + graphicInfo.getHeight();
} List<FlowNode> flowNodes = gatherAllFlowNodes(bpmnModel);
for (FlowNode flowNode : flowNodes) { GraphicInfo flowNodeGraphicInfo = bpmnModel.getGraphicInfo(flowNode.getId()); // width
if (flowNodeGraphicInfo.getX() + flowNodeGraphicInfo.getWidth() > maxX) {
maxX = flowNodeGraphicInfo.getX() + flowNodeGraphicInfo.getWidth();
}
if (flowNodeGraphicInfo.getX() < minX) {
minX = flowNodeGraphicInfo.getX();
}
// height
if (flowNodeGraphicInfo.getY() + flowNodeGraphicInfo.getHeight() > maxY) {
maxY = flowNodeGraphicInfo.getY() + flowNodeGraphicInfo.getHeight();
}
if (flowNodeGraphicInfo.getY() < minY) {
minY = flowNodeGraphicInfo.getY();
} for (SequenceFlow sequenceFlow : flowNode.getOutgoingFlows()) {
List<GraphicInfo> graphicInfoList = bpmnModel.getFlowLocationGraphicInfo(sequenceFlow.getId());
for (GraphicInfo graphicInfo : graphicInfoList) {
// width
if (graphicInfo.getX() > maxX) {
maxX = graphicInfo.getX();
}
if (graphicInfo.getX() < minX) {
minX = graphicInfo.getX();
}
// height
if (graphicInfo.getY() > maxY) {
maxY = graphicInfo.getY();
}
if (graphicInfo.getY()< minY) {
minY = graphicInfo.getY();
}
}
}
} int nrOfLanes = 0;
for (Process process : bpmnModel.getProcesses()) {
for (Lane l : process.getLanes()) { nrOfLanes++; GraphicInfo graphicInfo = bpmnModel.getGraphicInfo(l.getId());
// // width
if (graphicInfo.getX() + graphicInfo.getWidth() > maxX) {
maxX = graphicInfo.getX() + graphicInfo.getWidth();
}
if (graphicInfo.getX() < minX) {
minX = graphicInfo.getX();
}
// height
if (graphicInfo.getY() + graphicInfo.getHeight() > maxY) {
maxY = graphicInfo.getY() + graphicInfo.getHeight();
}
if (graphicInfo.getY() < minY) {
minY = graphicInfo.getY();
}
}
} // Special case, see http://jira.codehaus.org/browse/ACT-1431
if (flowNodes.size() == 0 && bpmnModel.getPools().size() == 0 && nrOfLanes == 0) {
// Nothing to show
minX = 0;
minY = 0;
} return new ProcessDiagramCanvas((int) maxX + 10,(int) maxY + 10, (int) minX, (int) minY);
}
}
2.2 图片的裁剪：
还是activiti的源码：（org.activiti.engine.impl.bpmn.diagram.ProcessDiagramCanvas.generateImage(String)）
/**// 此处的最小x和最小y减去了5
* Generates an image of what currently is drawn on the canvas.
*
* Throws an {@link ActivitiException} when {@link #close()} is already
* called.
*/
public InputStream generateImage(String imageType) {
if (closed) {
throw new ActivitiException("ProcessDiagramGenerator already closed");
} ByteArrayOutputStream out = new ByteArrayOutputStream();
try {
// Try to remove white space
minX = (minX <= 5) ? 5 : minX;
minY = (minY <= 5) ? 5 : minY;
BufferedImage imageToSerialize = processDiagram;
if (minX >= 0 && minY >= 0) {
// 此处的最小x和最小y减去了5
imageToSerialize = processDiagram.getSubimage(minX - 5, minY - 5, canvasWidth - minX + 5, canvasHeight - minY + 5); // 此处可以看到，activiti对图像做了裁剪的操作。
}
ImageIO.write(imageToSerialize, imageType, out);
} catch (IOException e) {
throw new ActivitiException("Error while generating process image", e);
} finally {
IoUtil.closeSilently(out);
}
return new ByteArrayInputStream(out.toByteArray());
}
imageToSerialize = processDiagram.getSubimage(minX - 5, minY - 5, canvasWidth - minX + 5, canvasHeight - minY + 5); // 此处可以看到，activiti对图像做了裁剪的操作。
}
ImageIO.write(imageToSerialize, imageType, out);
} catch (IOException e) {
throw new ActivitiException("Error while generating process image", e);
} finally {
IoUtil.closeSilently(out);
}
return new ByteArrayInputStream(out.toByteArray());
}
2.3 我们自己的各个节点的信息获取
@RequestMapping("/getProcessTrace")// 下方使用反射获取最小的x和y，仔细看就会发现调用的是上方2.1节的方法
@ResponseBody
/**
* 获取各个节点的具体的信息
* @param wfKey
* 流程定义的key
* @return
*/
public List<Map<String, Object>> getProcessTrace(String wfKey) throws Exception {
List<Map<String, Object>> activityInfos = new ArrayList<Map<String, Object>>();
RepositoryService repositoryService = processEngine.getRepositoryService();
ProcessDefinition pd = repositoryService.createProcessDefinitionQuery().processDefinitionKey(wfKey).latestVersion().singleResult();
ProcessDefinitionEntity processDefinition = (ProcessDefinitionEntity) ((RepositoryServiceImpl) repositoryService).getDeployedProcessDefinition(pd.getId());
List<ActivityImpl> activitiList = processDefinition.getActivities();
InputStream xmlIs = repositoryService.getResourceAsStream(processDefinition.getDeploymentId(), processDefinition.getResourceName());
BpmnModel bm = new BpmnXMLConverter().convertToBpmnModel(new InputStreamSource(xmlIs), false, true); // 下方使用反射获取最小的x和y，仔细看就会发现调用的是上方2.1节的方法
Class<?> clazz = Class.forName("org.activiti.engine.impl.bpmn.diagram.ProcessDiagramGenerator");
Method method = clazz.getDeclaredMethod("initProcessDiagramCanvas", BpmnModel.class);
method.setAccessible(true);
ProcessDiagramCanvas pdc = (ProcessDiagramCanvas) method.invoke(clazz.newInstance(), bm); // 调用方法 clazz = Class.forName("org.activiti.engine.impl.bpmn.diagram.ProcessDiagramCanvas");
Field minXField = clazz.getDeclaredField("minX"); // 得到minX字段
Field minYField = clazz.getDeclaredField("minY");
minXField.setAccessible(true);
minYField.setAccessible(true);
int minX = minXField.getInt(pdc);// 最小的x值
int minY = minYField.getInt(pdc); // 最小的y的值
minX = minX > 0 ? minX - 5 : 0; // 此处为什么需要减5，上方2.2中activiti源码中有
minY = minY > 0 ? minY - 5 : 0;
for (ActivityImpl activity : activitiList) {
Map<String, Object> activityInfo = new HashMap<String, Object>();
activityInfo.put("width", activity.getWidth());
activityInfo.put("height", activity.getHeight());
activityInfo.put("x", activity.getX() - minX);
activityInfo.put("y", activity.getY() - minY);
activityInfo.put("actId", activity.getId());
activityInfo.put("name", activity.getProperty("name")); // ActivityImpl 中没有getName方法，所以此处需要这样获取。
activityInfos.add(activityInfo);
}
return activityInfos;
}
Class<?> clazz = Class.forName("org.activiti.engine.impl.bpmn.diagram.ProcessDiagramGenerator");
Method method = clazz.getDeclaredMethod("initProcessDiagramCanvas", BpmnModel.class);
method.setAccessible(true);
ProcessDiagramCanvas pdc = (ProcessDiagramCanvas) method.invoke(clazz.newInstance(), bm); // 调用方法 clazz = Class.forName("org.activiti.engine.impl.bpmn.diagram.ProcessDiagramCanvas");
Field minXField = clazz.getDeclaredField("minX"); // 得到minX字段
Field minYField = clazz.getDeclaredField("minY");
minXField.setAccessible(true);
minYField.setAccessible(true);
int minX = minXField.getInt(pdc);// 最小的x值
int minY = minYField.getInt(pdc); // 最小的y的值
minX = minX > 0 ? minX - 5 : 0; // 此处为什么需要减5，上方2.2中activiti源码中有
minY = minY > 0 ? minY - 5 : 0;
for (ActivityImpl activity : activitiList) {
Map<String, Object> activityInfo = new HashMap<String, Object>();
activityInfo.put("width", activity.getWidth());
activityInfo.put("height", activity.getHeight());
activityInfo.put("x", activity.getX() - minX);
activityInfo.put("y", activity.getY() - minY);
activityInfo.put("actId", activity.getId());
activityInfo.put("name", activity.getProperty("name")); // ActivityImpl 中没有getName方法，所以此处需要这样获取。
activityInfos.add(activityInfo);
}
return activityInfos;
}
3.在jsp页面上使用绝对定位，给点击的节点加上高亮。
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<style type="text/css">
.activity-attr{border-radius: 10px; border: 3px solid red; transition:ease-out 0.5s; box-shadow:0px 0px 9px red;}
#processKey{color: red;}
#flowImageAndRect{position: relative;overflow: scroll;height:300px; heibackground-image: url('${ctx}/resources/images/workflow/grid_10.png')}
body,html{margin: 0px;padding:0px;}
</style>
<script type="text/javascript">
$(function(){
var wfKey = '${param.wfKey}'; // 流程定义的key
var $flowImageAndRect = $('#flowImageAndRect');
$('#processKey').html('流程定义的key --> ' + wfKey);
// 加载流程图片
loadProcessImage(wfKey,$flowImageAndRect);
// 加载各节点信息，最终实现，在点击图片上的各节点时，出现高亮
setTimeout(function(){
loadProcessTrace(wfKey,$flowImageAndRect);
},200);
var $revClickRect = null; // 上次点击的图形
// 绑定click事件，点击实现，只有点击的不是同一个时，才显示红色的边框（如果多次点击同一个，红色的边框只出现一次）
$('#flowImageAndRect').off('click').on('click','.activity-attr',function(e){
var $this = $(this);
var prevFlag = false; // 是上一个图形，避免多次点击同一个
if($revClickRect){ // 说明不是第一次点击
prevFlag = ($revClickRect.attr('actId')!=$this.attr('actId')) ? false : true;// 说明2次点击的不是同一个
if(!prevFlag)
$revClickRect.css('opacity','0');
}
if(!prevFlag){ // 此处可以请求后台，加载相关的数据（多次点击同一个，下方可确保只执行一次）
$this.css('opacity','1'); // 显示当前的
$revClickRect = $this; // 将当前设置为上次点击的
$('#info').html('节点ID --> ' + $this.attr('actId') + " | " + "节点名称 --> " + $this.attr('name'));
}
});
});
/**
* 加载图片
*/
function loadProcessImage(wfKey,$flowImageAndRect){
var imageUrl = '${ctx}/workflow/monitor/genericImageByWfKey.do?wfKey='+wfKey;
// 加载图片
$('<img />',{
"src" : imageUrl,
"alt" : ''
}).appendTo($flowImageAndRect);
}
/**
* 加载流程中各节点的信息
* @param wfKey : 流程定义的key
* @param $flowImageAndRect
*/
function loadProcessTrace(wfKey,$flowImageAndRect){
var traceUrl = '${ctx}/workflow/monitor/getProcessTrace.do?wfKey='+wfKey;
$.getJSON(traceUrl,function(infos){
var html = "";
$.each(infos,function(i,v){
// 矩形的div
var $div = $('<div/>', {
'class': 'activity-attr'
}).css({
position: 'absolute',
left: v.x,
top: v.y,
width: v.width - 3,
height:v.height - 3,
opacity: 0,
zIndex: 100,
cursor : 'pointer'
}).attr({'actId':v.actId,'name':v.name});
html += $div.prop("outerHTML");
});
$('<div />',{'id':'processRect'}).html(html).appendTo($flowImageAndRect);
});
}
</script>
</head>
<body>
<div id="main">
<div id="flowImageAndRect">
</div>
<div id="processKey" style="font-size: 52px;text-align: center;margin-bottom: 50px;">
</div>
<div id="info" style="font-size: 52px;text-align: center;">
</div>
</div>
</body>
</html>到此，已经完成了。