itemcommanddemo.java

J2ME MIDP 2.0 无线设备编程的一些源码

//itemCommandDemo.java file
import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;

public class itemCommandDemo extends MIDlet implements CommandListener ,ItemCommandListener
{
    private Command exitCommand;//定义Command命令对象
    private Command pasteCommand, copyCommand, cutCommand;
    private Form form;
    //定义两个输入框
    private String strSave="" ;//保存被Copy，Cut的字符串
    private TextField tf1, tf2;//定义输入框
    StringItem strTitle;
    public itemCommandDemo()
    {
        exitCommand =new Command("Exit",Command.EXIT,1);
        pasteCommand =new Command("Paste",Command.SCREEN,1);
        copyCommand =new Command("Copy",Command.SCREEN,1);
        cutCommand =new Command("Cut",Command.SCREEN,1);
        //创建Form对象
        form = new Form("ItemCmd Demo");
        //添加文字标签到Form对象中
        strTitle = new StringItem("","Copy/Cut/Paste Demo");
        form.append(strTitle);
        //创建TextField输入框对象并添加到Form对象中
        tf1 = new TextField("Text1","",50,TextField.ANY);
        form.append(tf1);
        tf2 = new TextField("Text2","",50,TextField.ANY);
        form.append(tf2);
        //将Copy，Cut命令添加到tf1对象中
        tf1.addCommand(copyCommand);
        tf1.addCommand(cutCommand);
        tf1.addCommand(pasteCommand);
        tf1.setItemCommandListener(this);
        //将Paste命令添加到tf1对象中
        tf2.addCommand(copyCommand);
        tf2.addCommand(cutCommand);
        tf2.addCommand(pasteCommand);
        tf2.setItemCommandListener(this);
        //添加Form 对象的命令
        form.addCommand(exitCommand);
        form.setCommandListener(this);
    }

    protected void startApp(  ) throws MIDletStateChangeException
    {
        Display.getDisplay(this).setCurrent(form);
    }

    protected void pauseApp(  )
    {
    }

    protected void destroyApp( boolean p1 )
    {
    }

    public void commandAction(Command c,Displayable d)
    {
        if (c ==exitCommand)
        {
            destroyApp(false);
            notifyDestroyed();
        }
    }

    public void commandAction(Command c, Item item) 
    {
        if (c == copyCommand) 
        {
            //拷贝功能
            if(item instanceof TextField)
                strSave = ((TextField)item).getString();
        }
        else if (c == cutCommand) 
        {
            //剪切功能
            if(item instanceof TextField)
            {
                strSave = ((TextField)item).getString();
                ((TextField)item).setString("");
            }
        }
        else if (c == pasteCommand) 
        {
            //把剪贴板中内容插入光标位置
            if(item instanceof TextField)
                ((TextField)item).insert(strSave, ((TextField)item).getCaretPosition());
        }
    }
}