Following the example in CustomCanvas.java
I've managed to paint a JButton inside a custom Swing canvas for an mxCell with this code

        public void drawVertex(mxCellState state, String label)
        {
           
            Object value = ((mxCell) state.getCell()).getValue();
            Pattern p = (Pattern)value;
            System.out.println(p.length);
            MyPanel comp = new MyPanel();
            
            rendererPane.paintComponent(g, comp, graphComponent,
                    (int) (state.getX()   translate.getX()),
                    (int) (state.getY()   translate.getY()),
                    (int) state.getWidth(), (int) state.getHeight(), true);
            
            g.setColor(Color.GREEN);
            for (int i = 0; i < p.length; i  ) {
                JButton b = new JButton("");
                b.addActionListener(new ActionListener() {
                    public void actionPerformed(ActionEvent e) {
                       System.out.println("click,click");
                    }          
                 });
                rendererPane.paintComponent(g, b, graphComponent,
                    (int) (state.getX()   translate.getX() i*state.getWidth()/p.length),
                    (int) (state.getY()   translate.getY()),
                    (int) state.getWidth()/p.length, (int) state.getHeight(), true);
            }
        }

the button gets painted but it isn't working and if I click it nothing happens

CodePudding user response：

If you want the component to be interactive, you have to add it to container (which itself is added to another container, eventually reaching a JFrame). What you have now just paints it into a cell.

Theoretically you could bend-over-backwards to intercept clicks to the cell and forward them to the JButton, but that's probably not a sustainable approach.