Android 按下tab键时向下移动

我试图将焦点移到下一个字段/按钮，但它似乎不起作用。以下是我目前拥有的：

    @Override
public boolean dispatchKeyEvent(KeyEvent event) {
    if (event.getKeyCode() == KeyEvent.KEYCODE_TAB) 
    {   
        //move down here once I figure it out..
        mEmailvalue.getNextFocusDownId();
        return true;

       }  
    return super.dispatchKeyEvent(event);
}

试试这个：

public boolean dispatchKeyEvent(KeyEvent event) {
    if (event.getKeyCode() == KeyEvent.KEYCODE_TAB && event.getAction()==KeyEvent.ACTION_DOWN) {
        View currentFocus = getCurrentFocus();
        if (currentFocus!=null) {
            View next = currentFocus.focusSearch(View.FOCUS_DOWN);
            if (next!=null) {
                next.requestFocus();
            }
        }
        return true;
    }  
    return super.dispatchKeyEvent(event);
}