ticker在screen类中被定义为一个域（Field），它可以被连接到任何screen类的子集中。在下面的例子中，我们将展示如何将ticker连接到列表(List)和alert对象中。


注意：以下例子基于MIDP和CLDC 1.0.3


源代码：

/*--------------------------------------------------
* TickerExample.java
*-------------------------------------------------*/
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;

public class TickerExample extends MIDlet implements CommandListener
{
  private Display display;   // 对显示对象的引用Reference to Display object
  private List lsProducts;   // 主产品列表
  private Alert alHelp;      // 显现文字和图像的警告板
  private Ticker tkSale;     // 对现在销售的提示
  private Command cmExit;    // 退出命令 
  public TickerExample()
  {
    display = Display.getDisplay(this);
    
    cmExit = new Command("Exit", Command.SCREEN, 1);

    tkSale = new Ticker("Current Sale: Bob's Pretty Good Laptop only $529.00");

    lsProducts = new List("Products", Choice.IMPLICIT);
    lsProducts.append("Laptop", null);
    lsProducts.append("Printer", null);
    lsProducts.append("Help", null);    
    lsProducts.addCommand(cmExit);
    lsProducts.setCommandListener(this);
    lsProducts.setTicker(tkSale);
  }

  public void startApp()
  {
    display.setCurrent(lsProducts);
  }

  public void pauseApp()
  {   }

  public void destroyApp(boolean unconditional)
  {   }

  public void showAlert()
  {
    try
    {        
      // Create an image
      Image im = Image.createImage("/help.png");

      // Create Alert, add text and image, no sound
      alHelp = new Alert("Help Information", 
                          "Bob's Pretty Good Products...so much to choose from!", 
                          im, null);
      alHelp.setTimeout(Alert.FOREVER);                          
      alHelp.setTicker(tkSale);
    }    
    catch(Exception e)
    {
      System.out.println("Unable to read png image.");
    }
    
    // Display the Alert. Once dismissed, return to product list
    display.setCurrent(alHelp, lsProducts);      

  }

  public void commandAction(Command c, Displayable s)
  {
    
    if (c == List.SELECT_COMMAND)
    {
      switch (lsProducts.getSelectedIndex())
      {
        case 0:
          System.out.println("Laptop selected");            
          break;
  
        case 1:
          System.out.println("Printer selected");            
          break;
          
        case 2:
          showAlert();
          break;
      }
    }
    else if (c == cmExit)
    {
      destroyApp(true);
      notifyDestroyed();
    }
  }
}

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