Using the loadParams() method available for all NetCharts applets, a developer can easily control the display of one or more chart applets from another applet. The following example shows an HTML document that contains two applets, one of them contains a single button, while the other is a simple barchart. When the button is pressed, the background color of the barchart is changed to blue. This simple example of applet-to-applet control can be expanded, using the loadParams() method to implement many different control situations.
<title>Applet-To-Applet Control</title> <applet name=control code=Control.class width=200 height=100> </applet> <applet name=barchart code=NFBarchartApp.class width=450 height=250> <param name=NFParamScript value = ' Background = (white, NONE); Header = ("Weekday Network Load", black, "TimesRoman", 20); BarLabels = "Mon", "Tue", "Wed", "Thu", "Fri"; DataSets = ("Server #1", blue), ("Server #2", red); DataSet1 = 100, -25, 75, 63, -46; DataSet2 = 85, 45, 10, -67, 10; '> </applet>
import java.applet.*; import java.awt.*; public class Control extends Applet { private NFBarchartApp bar = null; public void init () { add (new Button("Change Background")); } public boolean action (Event e, Object o) { bar = (NFBarchartApp)getAppletContext().getApplet("barchart"); if (bar == null) { System.out.println ("Unable to access Barchart"); } else { bar.loadParams ("Background = (blue)"); bar.loadParams ("Update"); } return true; } }