我想用一个简单的ExpandableListView工作,我想不通,为什么我得到的NPE在ObtainView。我应该只有一个父和几个孩子应开设在点击他们的父母,但它总是崩溃,并显示在ObtainView NullPointerException异常。非常感谢!
Prima.java:
包com.descoper.rom;
进口的java.util.ArrayList;
进口android.app.ExpandableListActivity;
进口android.content.Context;
进口android.os.Bundle;
进口android.view.LayoutInflater;
进口android.widget.ExpandableListView;
公共类厦华扩展ExpandableListActivity
{
//创建ArrayList中持有父项和子项
私人的ArrayList<字符串> parentItems =新的ArrayList<字符串>();
私人的ArrayList<对象> childItems =新的ArrayList<对象>();
@覆盖
公共无效的onCreate(包savedInstanceState)
{
super.onCreate(savedInstanceState);
//创建扩展列表,并设置其属性
ExpandableListView expandableList = getExpandableListView();
expandableList.setDividerHeight(2);
expandableList.setGroupIndicator(空);
expandableList.setClickable(真正的);
//设置家长的项目
setGroupParents();
//设置子数据
setChildData();
//创建适配器
转接适配器=新的适配器(parentItems,childItems);
adapter.setInflater((LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE),这一点);
//设置适配器expandableList
expandableList.setAdapter(适配器);
expandableList.setOnChildClickListener(本);
}
//方法添加父项目
公共无效setGroupParents()
{
parentItems.add(Categorii);
}
//方法来设置每个父母的子数据
公共无效setChildData()
{
//添加子项的水果
ArrayList的<字符串>孩子=新的ArrayList<字符串>();
child.add(苹果);
child.add(芒果);
child.add(香蕉);
child.add(橙);
childItems.add(子);
}
}
Adapter.java:
包com.descoper.rom;
进口的java.util.ArrayList;
进口android.app.Activity;
进口android.view.LayoutInflater;
进口android.view.View;
进口android.view.View.OnClickListener;
进口android.view.ViewGroup;
进口android.widget.BaseExpandableListAdapter;
进口android.widget.CheckedTextView;
进口android.widget.TextView;
进口android.widget.Toast;
公共类适配器扩展BaseExpandableListAdapter
{
私人活动的活动;
私人的ArrayList<对象> childtems;
私人LayoutInflater充气;
私人的ArrayList<字符串> parentItems,儿童;
//构造
公共适配器(ArrayList中<字符串>父母的ArrayList<对象>子女)
{
this.parentItems =父母;
this.childtems =子女;
}
公共无效setInflater(LayoutInflater充气,活动活动)
{
this.inflater =充气;
this.activity =活动;
}
//方法getChildView自动为每个子视图调用。
公共查看getChildView1(INT groupPosition,最终诠释childPosition,布尔isLastChild,查看convertView,父母的ViewGroup)
{
孩子=(ArrayList的<字符串>)childtems.get(groupPosition);
TextView中的TextView = NULL;
如果(convertView == NULL){
convertView = inflater.inflate(R.layout.child,NULL);
}
//获取TextView的参考和设定值
TextView的=(的TextView)convertView.findViewById(R.id.textViewChild);
textView.setText(child.get(childPosition));
//设置ClickListener来处理子项的单击事件
convertView.setOnClickListener(新OnClickListener(){
公共无效的onClick(视图查看){
Toast.makeText(活动,child.get(childPosition)
Toast.LENGTH_SHORT).show();
}
});
返回convertView;
}
//方法getGroupView自动为每个父项目称为
公共查看getGroupView1(INT groupPosition,布尔isExpanded,查看convertView,父母的ViewGroup)
{
如果(convertView == NULL){
convertView = inflater.inflate(R.layout.categorii,NULL);
}
((CheckedTextView)convertView).setText(parentItems.get(groupPosition));
((CheckedTextView)convertView).setChecked(isExpanded);
返回convertView;
}
@覆盖
公共对象getChild(INT groupPosition,INT childPosition)
{
返回null;
}
@覆盖
众长getChildId(INT groupPosition,INT childPosition)
{
返回0;
}
@覆盖
公众诠释getChildrenCount(INT groupPosition)
{
返程((ArrayList中<字符串>)childtems.get(groupPosition))的大小()。
}
@覆盖
公共对象getGroup(INT groupPosition)
{
返回null;
}
@覆盖
公众诠释getGroupCount()
{
返回parentItems.size();
}
@覆盖
公共无效onGroupCollapsed(INT groupPosition)
{
super.onGroupCollapsed(groupPosition);
}
@覆盖
公共无效onGroupExpanded(INT groupPosition)
{
super.onGroupExpanded(groupPosition);
}
@覆盖
众长getGroupId(INT groupPosition)
{
返回0;
}
@覆盖
公共布尔hasStableIds()
{
返回false;
}
@覆盖
公共布尔isChildSelectable(INT groupPosition,INT childPosition)
{
返回false;
}
@覆盖
公共查看getGroupView(INT groupPosition,布尔isExpanded,
查看convertView,ViewGroup中父){
// TODO自动生成方法存根
返回null;
}
@覆盖
公共查看getChildView(INT groupPosition,INT childPosition,
布尔isLastChild,查看convertView,ViewGroup中父){
// TODO自动生成方法存根
返回null;
}
}
parent.xml:
< XML版本=1.0编码=UTF-8&GT?;
< LinearLayout中的xmlns:机器人=http://schemas.android.com/apk/res/android
机器人:layout_width =match_parent
机器人:layout_height =match_parent
机器人:方向=垂直
机器人:背景=@可绘制/ backg1
机器人:重力=中心|顶
>
< CheckedTextView
的xmlns:机器人=http://schemas.android.com/apk/res/android
的xmlns:工具=http://schemas.android.com/tools
机器人:ID =@ + ID / textViewGroupName
机器人:layout_width =WRAP_CONTENT
机器人:layout_height =60dp
机器人:layout_marginLeft =5DP
机器人:重力=center_vertical
机器人:文本=Categorii
机器人:TEXTSIZE =18dp
机器人:文字颜色=#FFFFFF
机器人:填充=10dp
机器人:TEXTSTYLE =黑体/>
< / LinearLayout中>
child.xml:
< LinearLayout中的xmlns:机器人=http://schemas.android.com/apk/res/android
的xmlns:工具=http://schemas.android.com/tools
机器人:layout_width =match_parent
机器人:layout_height =40dp
机器人:可点击=真
机器人:方向=垂直
机器人:以下属性来=40dp
>
<的LinearLayout
机器人:layout_width =match_parent
机器人:layout_height =39dp
机器人:重力=center_vertical>
< ImageView的
机器人:ID =@ + ID / childImage
机器人:layout_width =30dp
机器人:layout_height =30dp
机器人:layout_margin =5DP
机器人:背景=@可绘制/ ic_launcher
机器人:contentDescription =@空/>
<的TextView
机器人:ID =@ + ID / textViewChild
机器人:layout_width =WRAP_CONTENT
机器人:layout_height =WRAP_CONTENT
机器人:layout_marginLeft =5DP
机器人:文本=Categorii
机器人:TEXTSIZE =16SP
机器人:文字颜色=#1919A3
机器人:TEXTSTYLE =黑体/>
< / LinearLayout中>
<查看
机器人:layout_width =match_parent
机器人:layout_height =1DP
机器人:背景=@机器人:彩色/白/>
< / LinearLayout中>
logcat的:
10月5日至一十九号:18:25.180:E / AndroidRuntime(1361):致命异常:主要
10月5号至19日:18:25.180:E / AndroidRuntime(1361):工艺:com.descoper.rom,PID:1361
10月5号至19日:18:25.180:E / AndroidRuntime(1361):显示java.lang.NullPointerException
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.widget.AbsListView.obtainView(AbsListView.java:2265)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.widget.ListView.makeAndAddView(ListView.java:1790)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.widget.ListView.fillDown(ListView.java:691)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.widget.ListView.fillFromTop(ListView.java:752)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.widget.ListView.layoutChildren(ListView.java:1630)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.widget.AbsListView.onLayout(AbsListView.java:2091)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.view.View.layout(View.java:14817)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.view.ViewGroup.layout(ViewGroup.java:4631)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.widget.FrameLayout.layoutChildren(FrameLayout.java:453)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.widget.FrameLayout.onLayout(FrameLayout.java:388)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.view.View.layout(View.java:14817)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.view.ViewGroup.layout(ViewGroup.java:4631)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.widget.LinearLayout.setChildFrame(LinearLayout.java:1671)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.widget.LinearLayout.layoutVertical(LinearLayout.java:1525)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.widget.LinearLayout.onLayout(LinearLayout.java:1434)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.view.View.layout(View.java:14817)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.view.ViewGroup.layout(ViewGroup.java:4631)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.widget.FrameLayout.layoutChildren(FrameLayout.java:453)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.widget.FrameLayout.onLayout(FrameLayout.java:388)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.view.View.layout(View.java:14817)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.view.ViewGroup.layout(ViewGroup.java:4631)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.view.ViewRootImpl.performLayout(ViewRootImpl.java:1987)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1744)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1000)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.view.ViewRootImpl $ TraversalRunnable.run(ViewRootImpl.java:5670)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.view.Choreographer $ CallbackRecord.run(Choreographer.java:761)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.view.Choreographer.doCallbacks(Choreographer.java:574)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.view.Choreographer.doFrame(Choreographer.java:544)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.view.Choreographer $ FrameDisplayEventReceiver.run(Choreographer.java:747)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.os.Handler.handleCallback(Handler.java:733)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.os.Handler.dispatchMessage(Handler.java:95)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.os.Looper.loop(Looper.java:136)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在android.app.ActivityThread.main(ActivityThread.java:5017)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在java.lang.reflect.Method.invokeNative(本机方法)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在java.lang.reflect.Method.invoke(Method.java:515)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:779)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
10月5号至19日:18:25.180:E / AndroidRuntime(1361):在dalvik.system.NativeStart.main(本机方法)
解决方案
您在返回空
从 getChild()
和 getGroup()
。你应该从你的数据结构返回相应的组和子项。
另外,你正在返回空
从 getChildView()
和 getGroupView()
。在这里,你应该返回一个查看
,将重新present孩子和组浏览
分别。
我建议你阅读有关 适配器
以及它们如何工作。
I'm trying to work with a simple ExpandableListView and I can't figure out why I get that NPE at ObtainView. I should have only one parent and few more children which should be opened on click on the parent of them, but it keeps crashing and showing NullPointerException on ObtainView. Thanks a lot !
Prima.java:
package com.descoper.rom;
import java.util.ArrayList;
import android.app.ExpandableListActivity;
import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.widget.ExpandableListView;
public class Prima extends ExpandableListActivity
{
// Create ArrayList to hold parent Items and Child Items
private ArrayList<String> parentItems = new ArrayList<String>();
private ArrayList<Object> childItems = new ArrayList<Object>();
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
// Create Expandable List and set it's properties
ExpandableListView expandableList = getExpandableListView();
expandableList.setDividerHeight(2);
expandableList.setGroupIndicator(null);
expandableList.setClickable(true);
// Set the Items of Parent
setGroupParents();
// Set The Child Data
setChildData();
// Create the Adapter
Adapter adapter = new Adapter(parentItems, childItems);
adapter.setInflater((LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE), this);
// Set the Adapter to expandableList
expandableList.setAdapter(adapter);
expandableList.setOnChildClickListener(this);
}
// method to add parent Items
public void setGroupParents()
{
parentItems.add("Categorii");
}
// method to set child data of each parent
public void setChildData()
{
// Add Child Items for Fruits
ArrayList<String> child = new ArrayList<String>();
child.add("Apple");
child.add("Mango");
child.add("Banana");
child.add("Orange");
childItems.add(child);
}
}
Adapter.java:
package com.descoper.rom;
import java.util.ArrayList;
import android.app.Activity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.BaseExpandableListAdapter;
import android.widget.CheckedTextView;
import android.widget.TextView;
import android.widget.Toast;
public class Adapter extends BaseExpandableListAdapter
{
private Activity activity;
private ArrayList<Object> childtems;
private LayoutInflater inflater;
private ArrayList<String> parentItems, child;
// constructor
public Adapter(ArrayList<String> parents, ArrayList<Object> childern)
{
this.parentItems = parents;
this.childtems = childern;
}
public void setInflater(LayoutInflater inflater, Activity activity)
{
this.inflater = inflater;
this.activity = activity;
}
// method getChildView is called automatically for each child view.
public View getChildView1(int groupPosition, final int childPosition, boolean isLastChild, View convertView, ViewGroup parent)
{
child = (ArrayList<String>) childtems.get(groupPosition);
TextView textView = null;
if (convertView == null) {
convertView = inflater.inflate(R.layout.child, null);
}
// get the textView reference and set the value
textView = (TextView) convertView.findViewById(R.id.textViewChild);
textView.setText(child.get(childPosition));
// set the ClickListener to handle the click event on child item
convertView.setOnClickListener(new OnClickListener() {
public void onClick(View view) {
Toast.makeText(activity, child.get(childPosition),
Toast.LENGTH_SHORT).show();
}
});
return convertView;
}
// method getGroupView is called automatically for each parent item
public View getGroupView1(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent)
{
if (convertView == null) {
convertView = inflater.inflate(R.layout.categorii, null);
}
((CheckedTextView) convertView).setText(parentItems.get(groupPosition));
((CheckedTextView) convertView).setChecked(isExpanded);
return convertView;
}
@Override
public Object getChild(int groupPosition, int childPosition)
{
return null;
}
@Override
public long getChildId(int groupPosition, int childPosition)
{
return 0;
}
@Override
public int getChildrenCount(int groupPosition)
{
return ((ArrayList<String>) childtems.get(groupPosition)).size();
}
@Override
public Object getGroup(int groupPosition)
{
return null;
}
@Override
public int getGroupCount()
{
return parentItems.size();
}
@Override
public void onGroupCollapsed(int groupPosition)
{
super.onGroupCollapsed(groupPosition);
}
@Override
public void onGroupExpanded(int groupPosition)
{
super.onGroupExpanded(groupPosition);
}
@Override
public long getGroupId(int groupPosition)
{
return 0;
}
@Override
public boolean hasStableIds()
{
return false;
}
@Override
public boolean isChildSelectable(int groupPosition, int childPosition)
{
return false;
}
@Override
public View getGroupView(int groupPosition, boolean isExpanded,
View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
return null;
}
@Override
public View getChildView(int groupPosition, int childPosition,
boolean isLastChild, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
return null;
}
}
parent.xml:
<?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="vertical"
android:background="@drawable/backg1"
android:gravity="center|top"
>
<CheckedTextView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/textViewGroupName"
android:layout_width="wrap_content"
android:layout_height="60dp"
android:layout_marginLeft="5dp"
android:gravity="center_vertical"
android:text="Categorii"
android:textSize="18dp"
android:textColor="#FFFFFF"
android:padding="10dp"
android:textStyle="bold" />
</LinearLayout>
child.xml:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="40dp"
android:clickable="true"
android:orientation="vertical"
android:paddingLeft="40dp"
>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="39dp"
android:gravity="center_vertical" >
<ImageView
android:id="@+id/childImage"
android:layout_width="30dp"
android:layout_height="30dp"
android:layout_margin="5dp"
android:background="@drawable/ic_launcher"
android:contentDescription="@null" />
<TextView
android:id="@+id/textViewChild"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="5dp"
android:text="Categorii"
android:textSize="16sp"
android:textColor="#1919A3"
android:textStyle="bold" />
</LinearLayout>
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:background="@android:color/white" />
</LinearLayout>
logcat:
05-19 10:18:25.180: E/AndroidRuntime(1361): FATAL EXCEPTION: main
05-19 10:18:25.180: E/AndroidRuntime(1361): Process: com.descoper.rom, PID: 1361
05-19 10:18:25.180: E/AndroidRuntime(1361): java.lang.NullPointerException
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.widget.AbsListView.obtainView(AbsListView.java:2265)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.widget.ListView.makeAndAddView(ListView.java:1790)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.widget.ListView.fillDown(ListView.java:691)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.widget.ListView.fillFromTop(ListView.java:752)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.widget.ListView.layoutChildren(ListView.java:1630)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.widget.AbsListView.onLayout(AbsListView.java:2091)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.view.View.layout(View.java:14817)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.view.ViewGroup.layout(ViewGroup.java:4631)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.widget.FrameLayout.layoutChildren(FrameLayout.java:453)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.widget.FrameLayout.onLayout(FrameLayout.java:388)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.view.View.layout(View.java:14817)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.view.ViewGroup.layout(ViewGroup.java:4631)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1671)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1525)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.widget.LinearLayout.onLayout(LinearLayout.java:1434)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.view.View.layout(View.java:14817)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.view.ViewGroup.layout(ViewGroup.java:4631)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.widget.FrameLayout.layoutChildren(FrameLayout.java:453)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.widget.FrameLayout.onLayout(FrameLayout.java:388)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.view.View.layout(View.java:14817)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.view.ViewGroup.layout(ViewGroup.java:4631)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:1987)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1744)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1000)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5670)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.view.Choreographer$CallbackRecord.run(Choreographer.java:761)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.view.Choreographer.doCallbacks(Choreographer.java:574)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.view.Choreographer.doFrame(Choreographer.java:544)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:747)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.os.Handler.handleCallback(Handler.java:733)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.os.Handler.dispatchMessage(Handler.java:95)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.os.Looper.loop(Looper.java:136)
05-19 10:18:25.180: E/AndroidRuntime(1361): at android.app.ActivityThread.main(ActivityThread.java:5017)
05-19 10:18:25.180: E/AndroidRuntime(1361): at java.lang.reflect.Method.invokeNative(Native Method)
05-19 10:18:25.180: E/AndroidRuntime(1361): at java.lang.reflect.Method.invoke(Method.java:515)
05-19 10:18:25.180: E/AndroidRuntime(1361): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
05-19 10:18:25.180: E/AndroidRuntime(1361): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
05-19 10:18:25.180: E/AndroidRuntime(1361): at dalvik.system.NativeStart.main(Native Method)
解决方案
You are returning null
from getChild()
and getGroup()
. You should return the corresponding group and child items from your data structures.
Also, you are returning null
from getChildView()
and getGroupView()
. Here you should return a View
that will represent the child and group Views
respectively.
I suggest you read about Adapters
and how they work.