单击 Android ExpandableListView 会导致子项出现“未找到 ID”错误

Question

我有一个ExpandableListView，当我单击展开子项时，当我尝试在子项布局中更新TextView 上的文本时，它会引发“未找到”错误。如果我将此部分注释掉，则效果很好。我的项目基于我在这个地方找到的示例。谁能发现我哪里出错了？

这是子布局：

  <?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="horizontal" >

    <TextView android:id="@+id/breakdown_item_a"
        android:layout_height="40dip" 
        android:layout_width="40dip" 
        android:layout_marginLeft="40dip"
        android:text="A" />

    <TextView android:id="@+id/breakdown_item_b"
        android:layout_height="40dip" 
        android:layout_width="40dip" 
        android:layout_marginLeft="40dip"
        android:text="B" />
</LinearLayout>

然后是创建子视图的代码：

public View getChildView(int groupPosition, int childPosition,
        boolean isLastChild, View rowView, ViewGroup parent) { 
    if (rowView == null) {
        LayoutInflater inflater = (LayoutInflater) context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

        rowView = inflater.inflate(R.layout.list_level_breakdown_item, null);
    }
    // If I comment out the next few lines it works, else it crashes here
    ((TextView)rowView.findViewById(R.id.breakdown_item_a)).setText(this.getChild(groupPosition, childPosition).getA());            ((TextView)rowView.findViewById(R.id.breakdown_item_b)).setText(this.getChild(groupPosition, childPosition).getB());

    return rowView;
}

终于到了我的电脑，这是正在抛出的错误消息。查看堆栈跟踪，视图似乎有问题，而不是检索 Id 本身：

FATAL EXCEPTION: main
android.content.res.Resources$NotFoundException: String resource ID #0xa
at android.content.res.Resources.getText(Resources.java:247)
at android.widget.TextView.setText(TextView.java:3473)
at testing.android.arrayadapters.BreakdownArray.getChildView(BreakdownArray.java:50)
at android.widget.ExpandableListConnector.getView(ExpandableListConnector.java:450)
at android.widget.AbsListView.obtainView(AbsListView.java:2033)
at android.widget.ListView.measureHeightOfChildren(ListView.java:1244)
at android.widget.ListView.onMeasure(ListView.java:1155)
at android.view.View.measure(View.java:12723)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4698)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1369)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:660)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:553)
at android.view.View.measure(View.java:12723)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4698)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
at android.view.View.measure(View.java:12723)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4698)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
at android.view.View.measure(View.java:12723)
at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:1196)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:555)
at android.view.View.measure(View.java:12723)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4698)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
at android.view.View.measure(View.java:12723)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:812)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:553)
at android.view.View.measure(View.java:12723)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4698)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2092)
at android.view.View.measure(View.java:12723)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1064)
at android.view.ViewRootImpl.handleMessage(ViewRootImpl.java:2442)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4424)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
at dalvik.system.NativeStart.main(Native Method)

似乎它不喜欢测量某些东西。我已经更新了代码（布局和子视图）。我尝试将事物更新为固定宽度，看看是否有帮助。到目前为止没有运气会继续修补

Answer 1

难道只是因为你有2个ID完全相同的孩子，所以当Android被要求通过ID获取元素时，它不知道要获取哪个？...

<LinearLayout>
    <TextView android:id="@+id/breakdown_item" ...>
    <TextView android:id="@+id/breakdown_item" ...>
</LinearLayout>

您可能应该将孩子更改为具有不同的 ID，以便它们是唯一的，就像这样......

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="horizontal">
      <TextView android:id="@+id/first_breakdown_item" android:layout_width="0px" android:layout_height="wrap_content" android:layout_weight="0.5" android:text="A" /> 
      <TextView android:id="@+id/second_breakdown_item" android:layout_width="0px" android:layout_height="wrap_content" android:layout_weight="0.5" android:text="B" /> 
</LinearLayout>

Answer 2

好的，我找到了原因。似乎 getA() 方法因为它返回了一个 int 这导致它崩溃，因为它不会自动将其转换为字符串。所以这完全是无缘无故的痛苦：（对不起，混乱的家伙。但总体教训是：

如果您要分配 textview 的文本值，请在传递参数时始终显式转换为字符串，因为它不会引发错误……但在运行时会崩溃。

尽管看到它干杯。