如何創建自定義Choicefield的彈出窗口並調用它？

Question

我創建了我自己的簡單ChoiceField通過延長ObjectChoiceField ..這就像..

public class MyChoiceField extends ObjectChoiceField 
{ 

    public MyChoiceField(String label ,Object[] choices) 
    { 
     super(label, choices); 
    } 

    protected void layout(int width, int height) 
    { 
     setMinimalWidth(width/2-62); 
     super.layout(width, height); 
    } 

    public void paint(Graphics graphics) 
    { 
     super.paint(graphics); 
    }  
} 

現在我想，當我在自定義菜單（不是默認的彈出窗口，黑莓提供時選擇MyChoiceField以顯示我的選擇用戶點擊ChoiceField）..

我該如何實現它？示例代碼將很可觀.. 感謝

Answer 1

嘗試重寫方法fieldChangeNotify(int context)的ObjectChoiceField這樣的：

public class MyChoiceField extends ObjectChoiceField 
{ 

    public MyChoiceField(String label ,Object[] choices) 
    { 
     super(label, choices); 
    } 

    protected void layout(int width, int height) 
    { 
     setMinimalWidth(width/2-62); 
     super.layout(width, height); 
    } 

    protected void fieldChangeNotify(int context) { 

     int index = getSelectedIndex(); 

     try{ 
      VerticalFieldManager vfm = new VerticalFieldManager(); 

      vfm.add(new LabelField("[Pop Up Content]\nChoice Field Changed #\n"+choices[index]+" selected.")); 

      PopupScreen popUpScreen = new PopupScreen(vfm){ 
       public boolean onClose() 
       { 
        this.close(); 
        return true; 
       } 
      }; 

      UiApplication.getUiApplication().pushScreen(popUpScreen); 

     } catch(Exception exc) { 
      System.out.println("Exception in choiceField fieldChangeNotify"); 
     } 
    } 

    public void paint(Graphics graphics) 
    { 
     super.paint(graphics); 
    } 
} 

使用MyChoiceField現在有點像這樣：

String[] choices; // Keep This Global 
VerticalFieldManager vfm = new VerticalFieldManager(Manager.FIELD_VCENTER);    
choices = new String[2]; 
choices[0] = new String("Choice1"); 
choices[1] = new String("Choice2"); 
vfm.add(new MyChoiceField("Choise", choices)); 

讓我知道這個解決方案是否有效。