过滤器返回一个空（NULL）数组列表 [英] Filter returns an empty (null) array list
问题描述
我有一个包含微调，图像和一个TextView的ListView。在此之上的ListView我有一个EditText用户可以在其中输入他需要的项目名称和所有的相关项目已经在ListView被证明。
I have ListView that contains spinner, an image and a TextView. Above this ListView I have an EditText where a user can type his required item name and all the related items has been shown in the ListView.
我的code是工作到这里，但问题是，当我在搜索编辑框中它的输入字符串，当我开始删除字符列表视图只是消失，只存在一个空白屏幕。而在第一个包含纺纱厂已成功创建，但在搜索框中做过滤和删除所有字符不能创建视图后，在ListView
My code is working till here but the problem is when i enter string in the search edit box it does that and when i start to remove the characters the list view is just disappears and there is only a blank screen. while at first the listView that contains the spinners was created successfully but after doing filter and removing all characters in the search box the view cannot be created.
下面是用getFilter在LazyAdapter我的code，从BaseAdapter扩展
Here is my code of getFilter in LazyAdapter that extends from BaseAdapter
@SuppressLint("DefaultLocale")
public android.widget.Filter getFilter() {
return new android.widget.Filter() {
@SuppressLint("DefaultLocale")
@Override
protected FilterResults performFiltering(CharSequence constraint) {
FilterResults Result = new FilterResults();
// if constraint is empty return the original names
if (TextUtils.isEmpty(constraint)){
//Result.values = storedata;
Result.count = listDetails.size();
return Result;
}
ArrayList<items> Filtered_Names = new ArrayList<items>();
String filterString = constraint.toString().toLowerCase();
String filterableString;
for(int i = 0; i<listDetails.size(); i++){
items searchdata = listDetails.get(i);
String title = searchdata.title();
String id = searchdata.id();
String imageUrl = searchdata.imageUrl();
String pprice = searchdata.pprice();
String shippingPrice = searchdata.shippingPrice();
String stock = searchdata.stock();
filterableString = title+" "+id+" "+imageUrl+" "+pprice+" "+shippingPrice+" "+status+" "+stitle+" "+stock+"
if(filterableString.toLowerCase().contains(filterString)){
Filtered_Names.add(listDetails.get(i));
//Log.e("Added", String.valueOf(Filtered_Names.size()));
}
}
Result.values = Filtered_Names;
Result.count = Filtered_Names.size();
//Log.e("Results", Result.values.toString() + String.valueOf(Result.count));
return Result;
}
@Override
protected void publishResults(CharSequence constraint,
FilterResults results) {
// TODO Auto-generated method stub
@SuppressWarnings("unchecked")
ArrayList<items> resultList =(ArrayList<items>) results.values;
LazyAdapter.this.listDetails = resultList;
LazyAdapter.this.notifyDataSetChanged();
}
};
}
这是LazyAdapter的构造
This is the constructor of LazyAdapter
public LazyAdapte(Context context , ArrayList<items> list)
{
this.context = context;
listDetails = list;
downloader = new ImageDownloader();
}
这是我的getCount（）方法
And here is my getCount() Method
@Override
public int getCount() {
// TODO Auto-generated method stub
return listDetails == null ? 0 : listDetails.size();
}
和这里是code在活动
and here is the code in the Activity
public class ItemsActivity extends Activity{
EditText inputsearch;
LazyAdapter adapter;
ArrayList<items> list;
Controller control;
@SuppressWarnings("unchecked")
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.items_activity);
RelativeLayout layout = (RelativeLayout) findViewById(R.id._view);
control = (Controller) getApplicationContext();
list = (ArrayList<items>) control.Table_items.GetData();
final ListView listview = (ListView)findViewById(R.id._data);
final LazyAdapter adapter = new LazyAdapter(this, list);
adapter.setLayout(this, layout);
listview.setAdapter(adapter);
inputSearch = (EditText) findViewById(R.id.inputsearch);
if(adapter!=null){
}
inputSearch.addTextChangedListener(new TextWatcher() {
@Override
public void onTextChanged(CharSequence cs, int arg1, int arg2, int arg3) {
try{
ItemsActivity.this.adapter.getFilter().filter(cs.toString());
}catch(Exception e){
e.printStackTrace();
}
}
@Override
public void beforeTextChanged(CharSequence arg0, int arg1, int arg2,
int arg3) {
// TODO Auto-generated method stub
}
@Override
public void afterTextChanged(Editable arg0) {
// TODO Auto-generated method stub
}
});
}
}
下面是堆栈跟踪
Android Runtime E:com.example.itemspac.LazyAdapter.<init>(LazyAdapter.java:36)
at com.example.itemspac.LazyAdapter.<init>(LazyAdapter.java:41)
下面的行号36是构造的公共LazyAdapter（上下文的背景下，ArrayList的＆LT;项目＆GT;清单） 41为 imagedownloader 在LazyAdapter
Here the line number 36 is of Constructor public LazyAdapter(Context context , ArrayList<items> list) and 41 is imagedownloader in LazyAdapter
推荐答案
在从code这下面的代码片段：
In this following snippet from your code:
if (TextUtils.isEmpty(constraint)){
//Result.values = storedata;
Result.count = listDetails.size();
return Result;
}
您还没有设置结果。值。这可能会导致您的适配器的getCount（）为空。
you have are not setting Result.values. This could result in your adapter's getCount() being null.
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