Android的列表視圖搜索得到空指針錯誤

Question

您好所有我想添加的搜索funcationality到ListView控件因我DOEN以下

@Override 
    public Filter getFilter() { 
     if (valueFilter == null) { 
      valueFilter = new ValueFilter(); 
     } 
     return valueFilter; 
    } 

    private class ValueFilter extends Filter { 

     @Override 
     protected FilterResults performFiltering(CharSequence constraint) { 
      FilterResults results = new FilterResults(); 

      if (constraint != null && constraint.length() > 0) { 

       for (int i = 0; i < mStringFilterList.size()-1; i++) { 
        if ((mStringFilterList.get(i).getServiceName().toString()) 
          .contains(constraint.toString())) { 
         // Contacts contacts = new Contacts(); 


         contacts.setServiceName(mStringFilterList.get(i) 
           .getServiceName()); 
         contacts.setAmount(mStringFilterList.get(i).getAmount() 
           + ""); 
         System.out 
           .println("mStringFilterList.get(i).getAmount()" 
             + mStringFilterList.get(i).getAmount()); 
         contacts.setTrnDate(mStringFilterList.get(i) 
           .getTrnDate()); 
         System.out 
           .println("mStringFilterList.get(i).getTrnDate()" 
             + mStringFilterList.get(i).getTrnDate()); 
         filterList.add(contacts); 
        } 
       } 
       results.count = filterList.size(); 
       results.values = filterList; 
      } else { 
       results.count = mStringFilterList.size(); 
       results.values = mStringFilterList; 
      } 
      return results; 
     } 

     @Override 
     protected void publishResults(CharSequence constraint, 
       FilterResults results) { 
      list=(ArrayList<Contacts>) results.values; 

      notifyDataSetChanged(); 
     } 

    } 

} 

但在mStringFilterList.get(i).getServiceName().toString())

Answer 1

得到錯誤更新getCount()方法：

@Override 
public int getCount() { 
    return list.size(); 
} 

原因：您需要退貨號碼的元素存儲在ArrayList。

完成