LWUIT与LCDUI的结合

Lwuit与Lcdui可以相互调用，如果需要在一个Midlet中同时使用Lwuit和Lcdui库，需要在Midlet中保留一个Lcdui Display的全局变量，可以在startApp方法中初始化。示例如下：

private javax.microedition.lcdui.Display lcduiDisplay;

//....

public void startMIDlet() {
//...
    lcduiDisplay = Display.getDisplay(this);
//...
}

如果是从Lwuit切换到Lcdui，通过使用Lcdui Display的setCurrent方法，示例如下：

lcduiDisplay.setCurrent(lcduiForm);

如果是从Lcdui切换到Lwuit，先初始化Lwuit Display，然后调用Component的show方法，示例如下：

com.sun.lwuit.Display.init(this);
com.sun.lwuit.Form lwuitForm = new com.sun.lwuit.Form("LWUIT FORM");
//...
lwuitForm.show();

附源代码：

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

package DemoLwuitLcdui;

import com.sun.lwuit.events.ActionEvent;
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;

/**
 * @author Administrator
 */
public class DemoLwuitLcduiMIDlet extends MIDlet implements CommandListener {

    private boolean midletPaused = false;

    //<editor-fold defaultstate="collapsed" desc=" Generated Fields ">//GEN-BEGIN:|fields|0|
    private Command exitCommand;
    private Command switchToLwuitFormCommand;
    private Form lcduiForm;
    private StringItem stringItem;
    //</editor-fold>//GEN-END:|fields|0|

    private com.sun.lwuit.Display lwuitDisplay;
    private javax.microedition.lcdui.Display lcduiDisplay;
    /**
     * The DemoLwuitLcduiMIDlet constructor.
     */
    public DemoLwuitLcduiMIDlet() {
    }

    //<editor-fold defaultstate="collapsed" desc=" Generated Methods ">//GEN-BEGIN:|methods|0|
    //</editor-fold>//GEN-END:|methods|0|

    //<editor-fold defaultstate="collapsed" desc=" Generated Method: initialize ">//GEN-BEGIN:|0-initialize|0|0-preInitialize
    /**
     * Initilizes the application.
     * It is called only once when the MIDlet is started. The method is called before the <code>startMIDlet</code> method.
     */
    private void initialize() {//GEN-END:|0-initialize|0|0-preInitialize
        // write pre-initialize user code here
//GEN-LINE:|0-initialize|1|0-postInitialize
        // write post-initialize user code here
    }//GEN-BEGIN:|0-initialize|2|
    //</editor-fold>//GEN-END:|0-initialize|2|

    //<editor-fold defaultstate="collapsed" desc=" Generated Method: startMIDlet ">//GEN-BEGIN:|3-startMIDlet|0|3-preAction
    /**
     * Performs an action assigned to the Mobile Device - MIDlet Started point.
     */
    public void startMIDlet() {//GEN-END:|3-startMIDlet|0|3-preAction
        // write pre-action user code here
        switchDisplayable(null, getLcduiForm());//GEN-LINE:|3-startMIDlet|1|3-postAction
        //lwuitDisplay = com.sun.lwuit.Display.getInstance();
        lcduiDisplay = Display.getDisplay(this);
        // write post-action user code here
    }//GEN-BEGIN:|3-startMIDlet|2|
    //</editor-fold>//GEN-END:|3-startMIDlet|2|

    //<editor-fold defaultstate="collapsed" desc=" Generated Method: resumeMIDlet ">//GEN-BEGIN:|4-resumeMIDlet|0|4-preAction
    /**
     * Performs an action assigned to the Mobile Device - MIDlet Resumed point.
     */
    public void resumeMIDlet() {//GEN-END:|4-resumeMIDlet|0|4-preAction
        // write pre-action user code here
//GEN-LINE:|4-resumeMIDlet|1|4-postAction
        // write post-action user code here
    }//GEN-BEGIN:|4-resumeMIDlet|2|
    //</editor-fold>//GEN-END:|4-resumeMIDlet|2|

    //<editor-fold defaultstate="collapsed" desc=" Generated Method: switchDisplayable ">//GEN-BEGIN:|5-switchDisplayable|0|5-preSwitch
    /**
     * Switches a current displayable in a display. The <code>display</code> instance is taken from <code>getDisplay</code> method. This method is used by all actions in the design for switching displayable.
     * @param alert the Alert which is temporarily set to the display; if <code>null</code>, then <code>nextDisplayable</code> is set immediately
     * @param nextDisplayable the Displayable to be set
     */
    public void switchDisplayable(Alert alert, Displayable nextDisplayable) {//GEN-END:|5-switchDisplayable|0|5-preSwitch
        // write pre-switch user code here
        Display display = getDisplay();//GEN-BEGIN:|5-switchDisplayable|1|5-postSwitch
        if (alert == null) {
            display.setCurrent(nextDisplayable);
        } else {
            display.setCurrent(alert, nextDisplayable);
        }//GEN-END:|5-switchDisplayable|1|5-postSwitch
        // write post-switch user code here
    }//GEN-BEGIN:|5-switchDisplayable|2|
    //</editor-fold>//GEN-END:|5-switchDisplayable|2|

    //<editor-fold defaultstate="collapsed" desc=" Generated Method: commandAction for Displayables ">//GEN-BEGIN:|7-commandAction|0|7-preCommandAction
    /**
     * Called by a system to indicated that a command has been invoked on a particular displayable.
     * @param command the Command that was invoked
     * @param displayable the Displayable where the command was invoked
     */
    public void commandAction(Command command, Displayable displayable) {//GEN-END:|7-commandAction|0|7-preCommandAction
        // write pre-action user code here
        if (displayable == lcduiForm) {//GEN-BEGIN:|7-commandAction|1|19-preAction
            if (command == exitCommand) {//GEN-END:|7-commandAction|1|19-preAction
                // write pre-action user code here
                exitMIDlet();//GEN-LINE:|7-commandAction|2|19-postAction
                // write post-action user code here
            } else if (command == switchToLwuitFormCommand) {//GEN-LINE:|7-commandAction|3|23-preAction
                // write pre-action user code here
                com.sun.lwuit.Display.init(this);
                com.sun.lwuit.Form lwuitForm = new com.sun.lwuit.Form("LWUIT FORM");
                lwuitForm.addComponent(new com.sun.lwuit.Label("Thi is a Lwuit Form."));
                lwuitForm.addComponent(new com.sun.lwuit.Label("Press Lcdui Form Command to "));
                lwuitForm.addComponent(new com.sun.lwuit.Label("switch to Lcdui Form."));
                com.sun.lwuit.Command switchToLcduiFormCommand = new com.sun.lwuit.Command("Lcdui Form");
                lwuitForm.addCommand(switchToLcduiFormCommand);
                lwuitForm.addCommandListener(new com.sun.lwuit.events.ActionListener() {

                    public void actionPerformed(ActionEvent ae) {
                        if (ae.getCommand().getCommandName().equals("Lcdui Form")) {
                            lcduiDisplay.setCurrent(lcduiForm);
                        }
                    }
                });
                lwuitForm.show();
//GEN-LINE:|7-commandAction|4|23-postAction
                // write post-action user code here
            }//GEN-BEGIN:|7-commandAction|5|7-postCommandAction
        }//GEN-END:|7-commandAction|5|7-postCommandAction
        // write post-action user code here
    }//GEN-BEGIN:|7-commandAction|6|
    //</editor-fold>//GEN-END:|7-commandAction|6|

    //<editor-fold defaultstate="collapsed" desc=" Generated Getter: exitCommand ">//GEN-BEGIN:|18-getter|0|18-preInit
    /**
     * Returns an initiliazed instance of exitCommand component.
     * @return the initialized component instance
     */
    public Command getExitCommand() {
        if (exitCommand == null) {//GEN-END:|18-getter|0|18-preInit
            // write pre-init user code here
            exitCommand = new Command("Exit", Command.EXIT, 0);//GEN-LINE:|18-getter|1|18-postInit
            // write post-init user code here
        }//GEN-BEGIN:|18-getter|2|
        return exitCommand;
    }
    //</editor-fold>//GEN-END:|18-getter|2|
    //</editor-fold>

    //<editor-fold defaultstate="collapsed" desc=" Generated Getter: lcduiForm ">//GEN-BEGIN:|14-getter|0|14-preInit
    /**
     * Returns an initiliazed instance of lcduiForm component.
     * @return the initialized component instance
     */
    public Form getLcduiForm() {
        if (lcduiForm == null) {//GEN-END:|14-getter|0|14-preInit
            // write pre-init user code here
            lcduiForm = new Form("LCDUI Form", new Item[] { getStringItem() });//GEN-BEGIN:|14-getter|1|14-postInit
            lcduiForm.addCommand(getExitCommand());
            lcduiForm.addCommand(getSwitchToLwuitFormCommand());
            lcduiForm.setCommandListener(this);//GEN-END:|14-getter|1|14-postInit
            // write post-init user code here
        }//GEN-BEGIN:|14-getter|2|
        return lcduiForm;
    }
    //</editor-fold>//GEN-END:|14-getter|2|

    //<editor-fold defaultstate="collapsed" desc=" Generated Getter: stringItem ">//GEN-BEGIN:|16-getter|0|16-preInit
    /**
     * Returns an initiliazed instance of stringItem component.
     * @return the initialized component instance
     */
    public StringItem getStringItem() {
        if (stringItem == null) {//GEN-END:|16-getter|0|16-preInit
            // write pre-init user code here
            stringItem = new StringItem("This is a Lcdui Form", "Press Lwuit Form Command to switch to lwuit form");//GEN-LINE:|16-getter|1|16-postInit
            // write post-init user code here
        }//GEN-BEGIN:|16-getter|2|
        return stringItem;
    }
    //</editor-fold>//GEN-END:|16-getter|2|
    //</editor-fold>

    //<editor-fold defaultstate="collapsed" desc=" Generated Getter: switchToLwuitFormCommand ">//GEN-BEGIN:|22-getter|0|22-preInit
    /**
     * Returns an initiliazed instance of switchToLwuitFormCommand component.
     * @return the initialized component instance
     */
    public Command getSwitchToLwuitFormCommand() {
        if (switchToLwuitFormCommand == null) {//GEN-END:|22-getter|0|22-preInit
            // write pre-init user code here
            switchToLwuitFormCommand = new Command("LwuitForm", Command.OK, 0);//GEN-LINE:|22-getter|1|22-postInit
            // write post-init user code here
        }//GEN-BEGIN:|22-getter|2|
        return switchToLwuitFormCommand;
    }
    //</editor-fold>//GEN-END:|22-getter|2|

    /**
     * Returns a display instance.
     * @return the display instance.
     */
    public Display getDisplay () {
        return Display.getDisplay(this);
    }

    /**
     * Exits MIDlet.
     */
    public void exitMIDlet() {
        switchDisplayable (null, null);
        destroyApp(true);
        notifyDestroyed();
    }

    /**
     * Called when MIDlet is started.
     * Checks whether the MIDlet have been already started and initialize/starts or resumes the MIDlet.
     */
    public void startApp() {
        if (midletPaused) {
            resumeMIDlet ();
        } else {
            initialize ();
            startMIDlet ();
        }
        midletPaused = false;
    }

    /**
     * Called when MIDlet is paused.
     */
    public void pauseApp() {
        midletPaused = true;
    }

    /**
     * Called to signal the MIDlet to terminate.
     * @param unconditional if true, then the MIDlet has to be unconditionally terminated and all resources has to be released.
     */
    public void destroyApp(boolean unconditional) {
    }

}