English 中文(简体)
获取儿童点击的无效指数例外
原标题:Getting nullpointerexception onChildClick

试图在可扩展列表视图中获取孩子的文本值 。

在child kick 活动中获得无效指针例外 。

 E/AndroidRuntime(358): at tournament.tracker.pkg.ExpList$5.onChildClick(ExpList.java:124)

第124行是 adpter.getChild 线。

我试图传递孩子的字符串值, 并点击其它活动 。

expList.setOnChildClickListener(new OnChildClickListener()
  {

    @Override
    public boolean onChildClick(ExpandableListView parent, View v, int groupPosition, int childPosition, long id) {
        ExpandableListAdapter adapter = getExpandableListAdapter();
        gametype = adapter.getChild(groupPosition, childPosition).toString();
        //---------------------
        Intent pullt = new Intent(ExpList.this, JsonActivity.class);
        Bundle bundle = new Bundle();
        bundle.putString("gametype", gametype);
        pullt.putExtras(bundle);
        pullt.putExtra("gametype", gametype);

        startActivity(pullt);
        //---------------------
        return false;
    }

  });

有人知道为什么这行不通吗?如果可能的话,请帮帮忙

EDIT

这里的适配器:

public class ExpAdapter extends BaseExpandableListAdapter {

      private Context myContext;
      public ExpAdapter(Context context) {
       myContext = context;
      }

      @Override
      public Object getChild(int groupPosition, int childPosition) {
       return null;
      }

      // Other code - not relevant
     }
最佳回答
public Object getChild(int groupPosition, int childPosition) {
    return null;
}

此函数将“ 坚固” ways to String () ) ) 将创建 Null Pointer 例外, 您必须执行此函数返回实际数据 。

一种固定办法可能是:

public Object getChild(int groupPosition, int childPosition) {
    return ExpList.arrChildelements[groupPosition][childPosition];;
}
问题回答

暂无回答




相关问题
Spring Properties File

Hi have this j2ee web application developed using spring framework. I have a problem with rendering mnessages in nihongo characters from the properties file. I tried converting the file to ascii using ...

Logging a global ID in multiple components

I have a system which contains multiple applications connected together using JMS and Spring Integration. Messages get sent along a chain of applications. [App A] -> [App B] -> [App C] We set a ...

Java Library Size

If I m given two Java Libraries in Jar format, 1 having no bells and whistles, and the other having lots of them that will mostly go unused.... my question is: How will the larger, mostly unused ...

How to get the Array Class for a given Class in Java?

I have a Class variable that holds a certain type and I need to get a variable that holds the corresponding array class. The best I could come up with is this: Class arrayOfFooClass = java.lang....

SQLite , Derby vs file system

I m working on a Java desktop application that reads and writes from/to different files. I think a better solution would be to replace the file system by a SQLite database. How hard is it to migrate ...

热门标签