爲什麼navigationMovement for FOCUSABLE LabeField在Blackberry中被繞過？

Question

我有一個LabelField whith的風格FOCUSABLE和許多可調焦的Field s之後，我忽略navigationMovement方法LabelField。

問題是：代碼永遠不會輸入navigationMovement的新實現中，但重點通常從LabelField移至下一個Field，而不通過navigationMovement實現！

PS，我也使用調試器來測試，以確保它永遠不會進入它的實現。

爲什麼會發生這種情況，以及如何捕獲FOCUSABLE LabelField的navigationMovement事件？

CODE：
這裏的類：

public abstract class FocusableLabelField extends LabelField { 
public boolean isDownUnfocused = false; 

public FocusableLabelField(String text) { 
    super(text, FOCUSABLE); 
} 

protected void drawFocus(Graphics graphics, boolean on) { 
     // DO NOTHING, FOCUS IS HANDLED IN PAINT 
} 

protected void paint(Graphics graphics) { 
    if(isDownUnfocused == true) 
     graphics.setColor(0xFFFFFF); 
    else { 
     if(isFocus()) 
      graphics.setColor(0xFFFFFF); 
     else { 
      graphics.setColor(0x777777); 
     } 
    } 
    super.paint(graphics); 
} 

protected void onFocus(int direction) { 
    isDownUnfocused = false; 
    onFocusing(); 
    super.onFocus(direction); 
} 

public abstract void onFocusing(); 

public void redraw() { 
    invalidate(); 
} 

protected boolean navigationMovement(int dx, int dy, int status, int time) { 
    //TODO CHECK WHY IT'S NOT ENTERING HERE ! 
    if(dy>0) 
     isDownUnfocused = true; 
    invalidate(); // IF REMOVED NO EFFECT WILL BE APPLIED 
    return super.navigationMovement(dx, dy, status, time); 
} 
} 

這裏就是我如何使用它的屏幕：

FocusableLabelField field = new FocusableLabelField("title") { 
    public void onFocusing() { 
     // some logic in the screen is done here ... 
    } 
} ; 

Answer 1

我只是跑你確切代碼在應用程序在5.0 8900模擬器和7.1 9900模擬器上，並且我做了看到你的navigationMovement()叫。但是，我不是100％肯定它在你想要的時候被調用。

我並不確切知道你想要做什麼，但看着上面的代碼，它看起來像你只是試圖爲焦點顏色添加自定義繪圖。是對的嗎？

如果是這樣，我不知道爲什麼你甚至需要重寫navigationMovement()。爲什麼不使用這樣的代碼：

public abstract class FocusableLabelField extends LabelField { 

    public FocusableLabelField(String text) { 
     super(text, FOCUSABLE); 
    } 

    protected void drawFocus(Graphics graphics, boolean on) { 
     // DO NOTHING, FOCUS IS HANDLED IN PAINT 
    } 

    protected void paint(Graphics graphics) { 
     int oldColor = graphics.getColor(); 
     if(isFocus()) 
     graphics.setColor(0xFFFFFF); 
     else { 
     graphics.setColor(0x777777); 
     } 
     super.paint(graphics); 
     graphics.setColor(oldColor); 
    } 

    protected void onFocus(int direction) { 
     onFocusing(); 
     invalidate(); 
     super.onFocus(direction); 
    } 

    protected void onUnfocus() { 
     invalidate(); 
     super.onUnfocus(); 
    } 

    public abstract void onFocusing(); 
}