JUNG-边缘采摘（鼠标事件）

Question

我在处理JUNG图上的选择事件时遇到了一些麻烦。 我一直在使用GraphMouseListener接口来侦听对顶点的单击，但是现在我需要添加对拾取边缘的支持，而我似乎找不到在文档中找到做到这一点的方法。

有指针吗？

谢谢

Answer 1

通过将项目侦听器添加到顶点和边的拾取状态来解决此问题：

visualizationViewer.getPickedEdgeState().addItemListener(new EdgePickListener());

Answer 2

您还可以创建自己的MouseEdgeListenerTranslator：

import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.Point2D;

import edu.uci.ics.jung.algorithms.layout.GraphElementAccessor;
import edu.uci.ics.jung.algorithms.layout.Layout;
import edu.uci.ics.jung.visualization.VisualizationViewer;

public class MouseEdgeListenerTranslator<V,E> extends MouseAdapter {

    private VisualizationViewer<V,E> vv;
    private GraphEdgeMouseListener<E> geml;

    public MouseEdgeListenerTranslator(GraphEdgeMouseListener<E> geml, VisualizationViewer<V,E> vv){
        this.geml = geml;
        this.vv = vv;
    }

    private E getEdge(Point2D point){
        Point2D p = point;
        GraphElementAccessor<V,E> pickSupport = vv.getPickSupport();
        Layout<V,E> layout = vv.getGraphLayout();
        E e = null;
        if(pickSupport != null){
            e = pickSupport.getEdge(layout, p.getX(), p.getY());
        }
        return e;
    }

    public void mouseClicked(MouseEvent me){
        E e = getEdge(me.getPoint());
        if(e != null){
            geml.graphClicked(e, me);
        }
    }

    public void mousePressed(MouseEvent me){
        E e = getEdge(me.getPoint());
        if(e != null){
            geml.graphPressed(e, me);
        }
    }

    public void mouseReleased(MouseEvent me){
        E e = getEdge(me.getPoint());
        if(e != null){
            geml.graphReleased(e, me);
        }
    }

}    

然后在GraphEdgeMouseListener中将其添加到您自己的VisualizationViewer子类中：

import edu.uci.ics.jung.visualization.VisualizationModel;
import edu.uci.ics.jung.visualization.VisualizationViewer;

public class MyVisualizationViewer<V,E> extends VisualizationViewer<V,E> {

    public MyVisualizationViewer(VisualizationModel<V,E> visualizationModel, Dimension size){
         super(visualizationModel, size);
     }

     public void addGraphEdgeMouseListener(GraphEdgeMouseListener<E> geml){
         addMouseListener(new MouseEdgeListenerTranslator<V,E>(geml, this));
    }

}

和

import java.awt.event.MouseEvent; 

public interface GraphEdgeMouseListener<E> {

    void graphClicked(E e, MouseEvent me);
    void graphPressed(E e, MouseEvent me);
    void graphReleased(E e, MouseEvent me);

}