子項ExpandableListView中的NullPointerException

Question

正在獲取NullPointerException當我單擊父項時。能否請你看看我的代碼爲此提出建議。我沒有得到任何下一步我必須爲這個錯誤採取什麼。試着通過看我的代碼建議我。logcat的屏幕截圖也張貼在這裏。

在此先感謝。

enter image description here

public class ExpandListAdapter extends BaseExpandableListAdapter { 

private Context context; 
private ArrayList<Group> groups; 

ImageLoader imageLoader = MyApplication.getInstance().getImageLoader(); 

public ExpandListAdapter(Context context, ArrayList<Group> groups) { 
    this.context = context; 
    this.groups = groups; 
} 

@Override 
public Object getChild(int groupPosition, int childPosition) { 
    ArrayList<Child> chList = groups.get(groupPosition).getItems(); 
    return chList.get(childPosition); 
} 

@Override 
public long getChildId(int groupPosition, int childPosition) { 
    return childPosition; 
} 

@Override 
public View getChildView(int groupPosition, int childPosition, 
         boolean isLastChild, View convertView, ViewGroup parent) { 

    Child child = (Child) getChild(groupPosition, childPosition); 
    if (convertView == null) { 
     LayoutInflater infalInflater = (LayoutInflater) context 
       .getSystemService(context.LAYOUT_INFLATER_SERVICE); 
     convertView = infalInflater.inflate(R.layout.child_item, null); 
    } 

    if (imageLoader == null) 
     imageLoader = MyApplication.getInstance().getImageLoader(); 

    TextView tv = (TextView) convertView.findViewById(R.id.country_name); 
    NetworkImageView iv = (NetworkImageView) convertView 
      .findViewById(R.id.flag); 

    tv.setText(child.getName().toString()); 
    iv.setImageUrl(String.valueOf(child.getImage()), imageLoader); 

    return convertView; 
} 

@Override 
public int getChildrenCount(int groupPosition) { 
    ArrayList<Child> chList = groups.get(groupPosition).getItems(); 
    return chList.size(); 
} 

@Override 
public Object getGroup(int groupPosition) { 
    return groups.get(groupPosition); 
} 

@Override 
public int getGroupCount() { 
    return groups.size(); 
} 

@Override 
public long getGroupId(int groupPosition) { 
    return groupPosition; 
} 

@Override 
public View getGroupView(int groupPosition, boolean isExpanded, 
         View convertView, ViewGroup parent) { 
    Group group = (Group) getGroup(groupPosition); 
    if (convertView == null) { 
     LayoutInflater inf = (LayoutInflater) context 
       .getSystemService(context.LAYOUT_INFLATER_SERVICE); 
     convertView = inf.inflate(R.layout.group_item, null); 
    } 
    TextView tv = (TextView) convertView.findViewById(R.id.group_name); 
    tv.setText(group.getName()); 
    return convertView; 
} 

@Override 
public boolean hasStableIds() { 
    return true; 
} 

@Override 
public boolean isChildSelectable(int groupPosition, int childPosition) { 
    return true; 
} 

}

XML文件：

<RelativeLayout 
xmlns:android="http://schemas.android.com/apk/res/android" 
android:layout_width="match_parent" 
android:layout_height="match_parent" 
android:paddingTop="4dp" 
android:paddingBottom="4dp" 
android:layout_marginLeft="50dp"> 

<TextView 
    android:id="@+id/name" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:layout_alignBottom="@+id/flag" 
    android:layout_marginBottom="14dp" 
    android:layout_marginLeft="29dp" 
    android:layout_toRightOf="@+id/flag" 
    android:text="TextView" 
    android:textSize="20dp" /> 

<com.android.volley.toolbox.NetworkImageView 
    android:id="@+id/flag" 
    android:layout_width="70dp" 
    android:layout_height="40dp" 
    android:layout_alignParentLeft="true" 
    android:layout_alignParentTop="true" 
    android:layout_marginLeft="27dp" 
    android:src="@drawable/ic_launcher" /> 

Answer 1

看來你正在使用的TextView不同的ID在getChildView方法

TextView tv = (TextView) convertView.findViewById(R.id.country_name); 

和

<TextView 
    android:id="@+id/name" 

此產品nullpointerexception.Therefore將其更改爲

TextView tv = (TextView) convertView.findViewById(R.id.name);