我想我可能会看到这个问题.查看ListView.

java的源代码,有一种机制可以使用在列表项中移动焦点的键事件.查看此方法之前的注释以及方法中间的注释块.

/**

* To avoid horizontal focus searches changing the selected item, we

* manually focus search within the selected item (as applicable), and

* prevent focus from jumping to something within another item.

* @param direction one of {View.FOCUS_LEFT, View.FOCUS_RIGHT}

* @return Whether this consumes the key event.

*/

private boolean handleHorizontalFocusWithinListItem(int direction) {

if (direction != View.FOCUS_LEFT && direction != View.FOCUS_RIGHT) {

throw new IllegalArgumentException("direction must be one of"

+ " {View.FOCUS_LEFT, View.FOCUS_RIGHT}");

}

final int numChildren = getChildCount();

if (mItemsCanFocus && numChildren > 0 && mSelectedPosition != INVALID_POSITION) {

final View selectedView = getSelectedView();

if (selectedView != null && selectedView.hasFocus() &&

selectedView instanceof ViewGroup) {

final View currentFocus = selectedView.findFocus();

final View nextFocus = FocusFinder.getInstance().findNextFocus(

(ViewGroup) selectedView, currentFocus, direction);

if (nextFocus != null) {

// do the math to get interesting rect in next focus' coordinates

currentFocus.getFocusedRect(mTempRect);

offsetDescendantRectToMyCoords(currentFocus, mTempRect);

offsetRectIntoDescendantCoords(nextFocus, mTempRect);

if (nextFocus.requestFocus(direction, mTempRect)) {

return true;

}

}

// we are blocking the key from being handled (by returning true)

// if the global result is going to be some other view within this

// list. this is to acheive the overall goal of having

// horizontal d-pad navigation remain in the current item.

final View globalNextFocus = FocusFinder.getInstance().findNextFocus(

(ViewGroup) getRootView(), currentFocus, direction);

if (globalNextFocus != null) {

return isViewAncestorOf(globalNextFocus, this);

}

}

}

return false;

}

单个列表元素中是否有多个可聚焦项目？如果是这样,此代码将使用Tab键.如果是这种情况,那么您可能想要使一些项目不可聚焦或考虑另一种设计选项.