转自：GMAIL 邮件列表 http://comments.gmane.org/gmane.comp.handhelds.android.devel/82840
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I've been fighting with styling on ExpandableListView as well (an area
that could use some improvement in a future release).
The problem with the current implementation is in the selector element
for the group expander.? It can be found in expander_group.xml and
looks like this:
<selector xmlns:android="http://schemas.android.com/apk/res/android">
??? <item
??????? android:state_expanded="true"
??????? android:drawable="@drawable/expander_ic_maximized" />
??? <item
??????? android:drawable="@drawable/expander_ic_minimized" />
</selector>
The problem is that it lacks a state for empty.? The code and
attributes support it (state_empty) but it isn't defined in here.
Here are the hypothetical (completely untested) steps you could use to
achieve this:
- Grab the existing expander_group.xml and put it into your drawable
directory.
- Modify it to include a section for the empty state with no image.
Something like this:
??? <item android:state_empty="true" android:drawable="@drawable/
empty"/>
- Modify your ExpandableListView element and set the group indicator
to be your private expander_group.xml
Let us know how it works out.? For myself, I need even more control so
I'm about to move to the "roll my own" stage.
?
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貌似这是个仍未修复的BUG，即便写了如下代码，问题仍然存在！
<item android:state_empty="true" android:drawable="@drawable/
empty"/>
?