JUNG - Edges with icons

Question

I am using JUNG for displaying network devices as graphs. Each edge is a link between two network elements. I want to add a picture exactly in the middle of the link. Currently my link looks like this: enter image description here

The code for it is:

vv.getRenderContext().setEdgeLabelTransformer(new Function<GraphLink,String>() {
            URL url = getClass().getResource("/icons/model/conn.radio.png");
            public String apply(GraphLink input) {
                return "<html><img src="+url+" height=14 width=14>";
            }});

As you can see the icon is adjacent with the link. Is there any option so the link could split the icon in two equals parts?

score 0 · Answer 1 · answered Nov 29 '16 at 19:02

tl;dr You want to tweak the edge label offset.

The position of the edge label is specified by a couple of properties, both accessible via the RenderContext:

The EdgeLabelClosenessTransformer, which should return a value in the range [0, 1], specifies the position of the label along the edge, that is, whether it should be closer to the source node (0) or the target node (1).
The edge label offset, which should return the distance from the edge to its label.

You can see how these properties are used (by default) in BasicEdgeLabelRenderer.

By default, the edge label offset is set to 10, which should make the edge label fairly close to, but not on top of, the edge. If you set it to 0:

vv.getRenderContext().setLabelOffset(0);

Then that should do what you want.

You may find it useful to experiment with EdgeLabelDemo.

JUNG - Edges with icons

1 Answers1