mxHierarchicalLayout无法按预期工作

我正在使用JGraphx在Swing面板中绘制图形，一切正常。 我尝试在目标单元格中​​插入两个单元格并且正在工作，但布局正在改变，所有单元格都不是水平的。

所以我的例子是：1）用一些单元格构建一个图形：

2）按顶部按钮并在Hello中添加两个单元格：

如您所见，问题是布局不再是水平的，即使我再次调用mxHierarchicalLayout。

谢谢你的回答！

package com.mxgraph.examples.swing; import java.awt.BorderLayout; import java.awt.Dimension; import java.awt.event.ActionEvent; import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent; import javax.swing.AbstractAction; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JOptionPane; import javax.swing.SwingConstants; import com.mxgraph.layout.hierarchical.mxHierarchicalLayout; import com.mxgraph.model.mxCell; import com.mxgraph.model.mxGraphModel; import com.mxgraph.model.mxICell; import com.mxgraph.swing.mxGraphComponent; import com.mxgraph.view.mxGraph; public class HelloWorld extends JFrame { private mxGraphComponent graphComponent; private int idgenerator = 0; public HelloWorld() { super("Hello, World!"); mxGraph graph = new mxGraph(); Object parent = graph.getDefaultParent(); graph.getModel().beginUpdate(); try { Object v1 = graph.insertVertex(parent, String.valueOf(++idgenerator), "Hello", 20, 20, 80, 30); Object v2 = graph.insertVertex(parent, String.valueOf(++idgenerator), "World!", 240, 150, 80, 30); graph.insertEdge(parent, String.valueOf(++idgenerator), "Edge", v1, v2); Object v3 = graph.insertVertex(parent, String.valueOf(++idgenerator), "Brando!", 240, 150, 80, 30); graph.insertEdge(parent, String.valueOf(++idgenerator), "Edge", v2, v3); Object v4 = graph.insertVertex(parent, String.valueOf(++idgenerator), "Jotaro!", 240, 150, 80, 30); graph.insertEdge(parent, String.valueOf(++idgenerator), "Edge", v3, v4); } finally { graph.getModel().endUpdate(); } graphComponent = new mxGraphComponent(graph); getContentPane().add(graphComponent, BorderLayout.CENTER); graphComponent.getGraphControl().addMouseListener(new MouseAdapter() { @Override public void mouseReleased(MouseEvent e) { Object cell = graphComponent.getCellAt(e.getX(), e.getY()); if (cell != null) { System.out.println("cell=" + graph.getLabel(cell)); JOptionPane.showMessageDialog(graphComponent, "cell=" + graph.getLabel(cell)); } } }); layoutGraph(graph); JButton change = new JButton("change"); change.setPreferredSize(new Dimension(100, 50)); change.setAction(new AbstractAction() { private static final long serialVersionUID = -1085992528036117542L; @Override public void actionPerformed(ActionEvent e) { mxGraph graph = graphComponent.getGraph(); mxGraphModel model = (mxGraphModel) graph.getModel(); mxCell before = (mxCell) model.getCells().get("2"); graph = insertIn(graph, before); layoutGraph(graph); } public mxGraph insertIn(mxGraph graph, mxCell target) { Object parent = graph.getDefaultParent(); graph.getModel().beginUpdate(); try { mxGraphModel model = (mxGraphModel) graph.getModel(); mxCell ed = (mxCell) target.getEdgeAt(0); mxICell t = ed.getTarget(); model.remove(ed); Object v1 = graph.insertVertex(parent, String.valueOf(++idgenerator), "HERE!", 20, 20, 80, 30); Object v2 = graph.insertVertex(parent, String.valueOf(++idgenerator), "HERE2", 20, 20, 80, 30); target.insert((mxICell) v1); target.insert((mxICell) v2); target.setCollapsed(false); graph.insertEdge(parent, String.valueOf(++idgenerator), "", v1, v2); graph.insertEdge(parent, String.valueOf(++idgenerator), "", v2, t); } finally { graph.getModel().endUpdate(); } return graph; } }); getContentPane().add(change, BorderLayout.PAGE_START); } public void layoutGraph(mxGraph graph) { mxHierarchicalLayout layout = new mxHierarchicalLayout(graph); layout.setOrientation(SwingConstants.WEST); layout.execute(graph.getDefaultParent()); } public static void main(String[] args) { HelloWorld frame = new HelloWorld(); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setSize(800, 400); frame.setVisible(true); } }