smart gwt TreeGrid addSelectionUpdatedHandler 无法获取所选记录

Question

我有一个treeGrid，并在客户端初始化树。并添加addSelectionUpdatedHandler的hander。棘手的是：它可以在第一时间获取选定的记录。 然后每当我下次选择该记录时，就会触发 SelectionUpdatedEvent，但所选记录始终为空。

public void afterScreenLoad() {
 treeGrid = (TreeGrid) BaseWidget.getById(getApp().getScreenName() + "_ListGrid");
 ...
 addTreeGridHandler();
 addDataToGrids();
}

private void addDataToGrids() {
        Criteria criteria = treeGrid.getCriteria();

        tree = new Tree();
        root = new TreeNode();
        root.setIsFolder(true);
        tree.setRoot(root);

        jobs.forEach(job -> {
            TreeNode jobNode = new TreeNode();
            jobNode.setAttribute(ID, job.getId());
            jobNode.setAttribute(NAME, job.getVin());
            jobNode.setIsFolder(true);
            tree.add(jobNode, root);
            job.getProcessSteps().forEach(step -> {
                TreeNode stepNode = new TreeNode();
                stepNode.setAttribute(ID, step.getId());
                stepNode.setAttribute(PARENT, job.getId());
                stepNode.setAttribute(NAME, step.getName());
                tree.add(stepNode, jobNode);
            });
        });
        ListGridField[] fields = treeGrid.getAllFields();
        assetsDataSourceIndex += 1;
        ClientDataSource clientDataSource = new ClientDataSource(fields, assetsDataSourceIndex, true);
        clientDataSource.setCacheData(tree.getAllNodes());
        treeGrid.setDataSource(clientDataSource);
        treeGrid.fetchData();
        treeGrid.setFields(fields);
    }

   private void addTreeGridHandler() {
        getActionUtil().addHandler(treeGrid.addDrawHandler(event -> treeGrid.getBody()
                .setCanSelectText(true)));
        treeGrid.addDataArrivedHandler((DataArrivedHandler) dataArrivedEvent -> {
            SC.logWarn("Data arrived");
            if (dataLoaded && !selectionChanged) {
                selectPreviousSelectedAssetInTreeGrid();
            }
        });
        getActionUtil().addHandler(treeGrid.addSelectionUpdatedHandler(this::selectionChanged));
    }

    private void selectionChanged(BrowserEvent selectEvent) {
        SC.logWarn(selectEvent.getSource().toString());
        TreeNode selectedRecord = treeGrid.getSelectedRecord();
        boolean jobSelected = isJobSelected();
        SC.logWarn("Selected record existed: " + (selectedRecord != null));
        ...
   }

有人可以帮忙吗？

Answer 1

我尝试重新创建您的问题（因为我无法运行您的代码），但我没有得到完全相同的行为。
相反，仅当取消选择 TreeGrid 中的记录（通过按住 Ctrl 键单击它）时，所选记录才为空。 这可能是您第二次单击该记录时发生的情况吗？第三次单击它会发生什么？

也许您可以在较小的可运行示例和帖子中重新创建您的问题。或者您可以从我的示例开始并模仿您的应用程序以查看问题何时发生。也许您甚至会找出它发生的原因。

因为问题可能是由于您的代码中的某些特定内容而发生的，可能是由于您的示例未显示的方法。

import com.smartgwt.client.widgets.Label;
import com.smartgwt.client.widgets.Window;
import com.smartgwt.client.widgets.tree.Tree;
import com.smartgwt.client.widgets.tree.TreeGrid;
import com.smartgwt.client.widgets.tree.TreeNode;

public class Test {
  private Label selectedLbl;
  private TreeGrid treeGrid;


  public Test() {
    Tree tree = new Tree();
    tree.setRoot(new TreeNode("Tree", 
        new TreeNode("Foo",
            new TreeNode("1"),
            new TreeNode("2")),
        new TreeNode("Bar", 
            new TreeNode("3"),
            new TreeNode("4"))));
    
    treeGrid = new TreeGrid();
    treeGrid.setData(tree);
    treeGrid.addDrawHandler(event2 -> treeGrid.getBody().setCanSelectText(true));
    treeGrid.addSelectionUpdatedHandler(event2 -> {
      TreeNode selectedNode = treeGrid.getSelectedRecord();
      selectedLbl.setContents("Selected: " + (selectedNode == null ? "null" : selectedNode.getName()));
    });
    
    selectedLbl = new Label("Selected: ");
    
    Window win = new Window();
    win.addItem(treeGrid);
    win.addItem(selectedLbl);
    win.setSize("300", "300");
    win.show();
  }
}