黑莓主屏上的代碼

Question

我正在構建一個黑莓設備的應用程序，它將在主屏幕上顯示一個代碼。我搜查了很多，但找不到解決方案。

我已經嘗試更新固定間隔後的背景圖像，但這會使手機非常慢。我不是主題開發者，但嘗試過並失敗了。我想從我的應用程序中更新股票代碼的文本。

請幫助我，我真的被困在這裏。在此先感謝

Answer 1

有在StackOverflow的 希望類似的職位，這將有助於你

Add A ticker to Blackberry Display

PLZ回來的情況下，這個亙古不變的解決您的問題

Answer 2

下面的代碼可以給你更多洞悉代碼 只需在下面的類中創建一個對象並傳遞所需的參數即可。這會讓你的工作完成。我猜這是

import java.util.Timer; 
import java.util.TimerTask; 
import net.rim.device.api.system.Display; 
import net.rim.device.api.ui.Color; 
import net.rim.device.api.ui.Field; 
import net.rim.device.api.ui.Font; 
import net.rim.device.api.ui.Graphics; 

public class TickerField extends Field { 
     String text; 
     static final int screenWidth = Display.getWidth(); 
     int offset; 
     private Timer timer = new Timer(); 
     final int delay = 30; 
     private static int fontH = Font.getDefault().getHeight(); 
     private int w; 
     private int h; 
     private int bgColor = Color.WHITE; 
     public TickerField(String text, int width, int height) { 
       this.text = text; 
       w = width; 
       h = height; 
       offset = w; 
       final int textWidth = Font.getDefault().getAdvance(text); 

       //schedule and start timertask 
       TimerTask timerTask = new TimerTask() { 
         public void run() { 
           offset--; 
           if (offset + textWidth == 0) { 
             offset = screenWidth; 
           } 
           invalidate(); 
         } 
       }; 
       timer.scheduleAtFixedRate(timerTask, delay, delay); 
     } 
     public TickerField(String text) { 
       this(text, screenWidth, fontH); 
     } 
     public TickerField(int width, int height) { 
       this("", width, height); 
     } 
     public TickerField() { 
       this("", screenWidth, fontH); 
     } 
     //set ticker text 
     public void setText(String text) { 
       this.text = text; 
     } 
     //get ticker text 
     public String getText() { 
       return text; 
     } 
     // implement layout to give specific arrangement to this field 
     // Invoke Math.min() to return the smaller of the user specified w and h, 
     // and the preferred width and height of the field. 
     protected void layout(int width, int height) { 
       width = Math.min(w, getPreferredWidth()); 
       height = Math.min(h, getPreferredHeight()); 
       setExtent(width, height); 
     } 
     // Implement the paint() to redraw the field with different 
     // offset controlled by timer task.That will give the 
     // ticker effect. 
     protected void paint(Graphics graphics) { 
       graphics.drawText(text, offset, 0); 
     } 

     public void setBgColor(int bgColor) { 
       this.bgColor = bgColor; 
     } 
     //Implement the paintBackground() method to change the 
     //background color of the field. 
     protected void paintBackground(Graphics g) { 
       g.setBackgroundColor(bgColor); 
       g.clear(); 
       super.paintBackground(g); 
     } 


     // Implement getPreferredWidth() and getPreferredHeight(), using the 
     // screenWidth and font height to make sure that the ticker does not exceed 
     // the dimensions of the 
     // component. 
     public int getPreferredWidth() { 
       return screenWidth; 
     } 
     public int getPreferredHeight() { 
       return fontH; 
     } 

} 

編碼快樂:)