如何更改黑莓中對象選擇字段的背景顏色？

Question

我想更改黑莓中對象選擇字段中所選項目的背景顏色？

Answer 1

嘗試這樣的示例代碼：

public class SamplePopupScreen extends PopupScreen 
{ 
    BitmapField bitmapField[]; 
    Bitmap bitmap=Bitmap.getBitmapResource("box-s6A.png"); 

    public SamplePopupScreen() 
    { 
     super(new VerticalFieldManager(),PopupScreen.DEFAULT_CLOSE); 
     createGUI(); 
    } 

    private void createGUI() 
    { 
     bitmapField=new BitmapField[3]; 
     add(new LabelField("Popup Screen",Field.FIELD_HCENTER)); 

     for(int i=0;i<3;i++) 
     { 
      VerticalFieldManager vr=new VerticalFieldManager(Field.FIELD_HCENTER|VERTICAL_SCROLL|VERTICAL_SCROLLBAR); 

      bitmapField[i]=new BitmapField(null,Field.FOCUSABLE|Field.FIELD_HCENTER) 
      { 
       protected void paint(Graphics g) 
       { 
        g.clear(); 
        g.drawText("LabelNunber", 0, 0); 
        if(isFocus()) 
        { 
         g.drawBitmap(0, 0, bitmap.getWidth(), bitmap.getHeight(), bitmap, 0, 0); 
         g.drawText("LabelNunber",0,0); 
        } 
       } 
       protected void layout(int width, int height) 
       { 
        super.layout(250, 50); 
        setExtent(250, 50); 
       } 
      }; 
      vr.add(bitmapField[i]); 
      add(vr); 
     } 
    } 
} 

和我得到這樣的：

Answer 2

閱讀BlackBerry API文檔Field.setBackground(Background background),Field.setBackground(int visual, Background background)和Background。