How to convert Application to Applet

I have an application which contains a number of different frames. I would like to modify the code so that I can also run it as an applet. I'm not sure what code needs to be changed or added. Also, my application makes use of dialog boxes, frame titles, etc...) Will these still work within an applet?

Thanks for your help!

Carey Boldenow
carey.boldenow@attws.com
boldecAsked:
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eugenemConnect With a Mentor Commented:
It depends on code. If your class extends Frame, move all widgets initialization from constructor to init(), your class should extend Applet, in main() create one Frame() and one instance of your class, run init() of your class, add your class to Frame. So when class is running as Applet, it uses init(), and when as application, it uses main(). There is an example. Just look at init/main functions.

// SpecTcl generated class test, version 1.1

package DFS;
import java.awt.*;

public class test extends java.applet.Applet {            

// a slot to hold an arbitrary object pointer that can
// be filled in by the app. and referenced in actions
public Object arg;

public Button button_1;

//methods to support form introspection
public static String names[] = {
      "button_1",
};
public String[] getNames() {
      return names;
}

//There should be an easier way to do this
public Object[] getWidgets() {
      Object[] list = new Object[1];
      list[0] = button_1;
      return list;
}

public void init() {

      // main panel
      GridBagLayout grid = new GridBagLayout();
      int rowHeights[] = {0,30,30};
      int columnWidths[] = {0,30,30};
      double rowWeights[] = {0.0,0.0,0.0};
      double columnWeights[] = {0.0,0.0,0.0};
      grid.rowHeights = rowHeights;
      grid.columnWidths = columnWidths;
      grid.rowWeights = rowWeights;
      grid.columnWeights = columnWeights;

      button_1 = new Button();
      button_1.setLabel("button");
      this.add(button_1);
      

      // Geometry management
      GridBagConstraints con = new GridBagConstraints();
      reset(con);
      con.gridx = 1;
      con.gridy = 1;
      con.anchor = GridBagConstraints.CENTER;
      con.fill = GridBagConstraints.NONE;
      grid.setConstraints(button_1, con);


      // Resize behavior management and parent heirarchy
      setLayout(grid);

      // Give the application a chance to do its initialization
      super.init();
}

public boolean handleEvent(Event event) {
      if (event.id==event.KEY_ACTION && event.key==event.F4 && event.modifiers==event.ALT_MASK) {  // Alt-F4 always exits
            System.exit(3);
      } else
            return super.handleEvent(event);
      return true;
}

public static void main(String[] args) {
    Frame f = new Frame("test Test");
    test win = new test();
    win.init();
    f.add("Center", win);
    f.pack();
    f.show();
}

private void reset(GridBagConstraints con) {
    con.gridx = GridBagConstraints.RELATIVE;
    con.gridy = GridBagConstraints.RELATIVE;
    con.gridwidth = 1;
    con.gridheight = 1;
 
    con.weightx = 0;
    con.weighty = 0;
    con.anchor = GridBagConstraints.CENTER;
    con.fill = GridBagConstraints.NONE;
 
    con.insets = new Insets(0, 0, 0, 0);
    con.ipadx = 0;
    con.ipady = 0;
}

}

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