How to get source and target of edge after any change on cell connect?

I'm programming a web application that use workflow. I used jgraph(Mxgraph) for designing workflow.

I will save workflow parts in database (activities, notifications, transitions). I need to get source and target of transitions. So how should I catch any changes on transitions in client?

I used before from these three events but don't work always. For example when I change connection target.

Editor.graph.connectionHandler.addListener(mxEvent.CONNECT, function (sender, evt) {
            console.log('connect');
});
Editor.graph.connectionHandler.addListener(mxEvent.START, function (sender, evt) {
            console.log('start');
});
Editor.graph.connectionHandler.addListener(mxEvent.RESET, function (sender, evt) {
            console.log('reset');
});

I found it. We can use mxEvent.Change event for getting any change on graph model.

        editor.graph.getModel().addListener(mxEvent.CHANGE, function (sender, evt) {
            editor.graph.validateGraph();
            var xml = getEditorXml(Editor);
            $("#BpmnXml").val(xml);

            //console.log(getCells_ByType("Start"));
            // /console.log(getCells_ByType("Task"));
            let connectors = getCells_ByType("Connector");
            if (connectors != null && connectors.length > 0) {
                connectors.forEach(element => {
                    var source = Editor.graph.getModel().getTerminal(element, true);
                    var target = Editor.graph.getModel().getTerminal(element, false);
                    setData(element, { FromActivityClientId: source.getId(), ToActivityClientId: target.getId() });
                });
            }
        });

function getCells_ByType(TypeCell) { // dar report estafede mishavad
    var AllCells = Editor.graph.getChildCells(Editor.graph.getDefaultParent(), true, true);
    var result = $.grep(AllCells, function (s) { return s.getValue().localName == TypeCell; });
    if (result.length != 0)
        return result;
    else
        return null;
}