eclipse 为 ExpandableListView 设置自定义指示器不起作用
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Setting a custom indicator for ExpandableListView isn't working
提问by Guy
So I'm trying to set a custom ExpandableListView indicator icon but it isn't working. I created an icon and saved it to drawable folder. Here are the icons:
所以我试图设置一个自定义的 ExpandableListView 指示器图标，但它不起作用。我创建了一个图标并将其保存到 drawable 文件夹中。以下是图标：
This is the selector:
这是选择器：
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="@drawable/arrow_up" android:state_empty="true"/>
<item android:drawable="@drawable/arrow_down" android:state_activated="true"/>
</selector>
ExpandableListView xml:
可扩展列表视图 xml：
<ExpandableListView
android:id="@+id/lvExp"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:groupIndicator="@drawable/custom_arrow" />
However, when I launch the app, there is not indicator at all. Any idea what I have done wrong?
但是，当我启动应用程序时，根本没有指示器。知道我做错了什么吗？
回答by tyczj
this should do the trick
这应该可以解决问题
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_expanded="true" android:drawable="@drawable/arrow_up" />
<item android:drawable="@drawable/arrow_down" />
</selector>
you wanted the state_expandedfor when the row gets expanded and then any other state besides expanded is just the normal down arrow. You should however handle the state_emptywhen there is nothing to expand to
state_expanded当行被扩展时，你想要for ，然后除了扩展之外的任何其他状态只是正常的向下箭头。然而，state_empty当没有什么可扩展的时候，你应该处理
回答by ecem
I think you just need to add this one line to your selector and change the arrow down condition:
我认为您只需要将这一行添加到您的选择器并更改向下箭头条件：
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="@drawable/arrow_up" android:state_empty="true"/>
<item android:drawable="@drawable/arrow_down" android:state_expanded="true"/>
<item android:drawable="@drawable/arrow_up" />
</selector>
