B4J Question How to access Javascript's Variable

var container = document.getElementById('container');

    // Create a graphic instance over the container
    var graphic = archer.create(container);

    // Tell the graphic where assets (e.g. images) are located
    graphic.document.setAssetRoot(assetUrl);

    // Load graphic and configuration
    graphic.loadUrl(graphicUrl, configUrl);

    // Wait until files are loaded
    graphic.on('ready', function () {

        // Make graphic fit into container bounds
        graphic.view.zoomToFit();

        // Enable zoom / pan with mouse
        graphic.view.enableMouse(true, true);

        // Set variable values
        graphic.setValue('TempUnit', false);
        graphic.setValue('TempValue', '1.2');

        // Add event listeners

    });