以下是代码，我使用了自定义适配器，并应用了Filter方法，现在当输入退格键时，ListView不会更新，当从项目活动切换回来时。请帮助我......以及如何在筛选列表中显示没有结果..
public class ItemListAdapter extends ArrayAdapter<ItemVO>
{
private ArrayList<ItemVO> itemList;
private ArrayList<ItemVO> fiems;
private static final int LONG_DELAY = 3500; // 3.5 seconds
private static final int SHORT_DELAY = 2000; // 2 seconds
private Context context;
private Filter filter;
public ItemListAdapter(Context context, int textViewResourceId,ArrayList<ItemVO> stateList)
{
super(context, textViewResourceId, stateList);
this.context = context;
this.itemList = new ArrayList<ItemVO>();
this.itemList.addAll(stateList);
this.fiems=new ArrayList<ItemVO>();
this.fiems.addAll(stateList);
}
private class ViewHolder
{
TextView code;
CheckBox name;
}
@Override
public View getView(int position, View convertView, ViewGroup parent)
{
ViewHolder holder = null;
Log.v("ConvertView", String.valueOf(position));
if (convertView == null)
{
LayoutInflater vi = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = vi.inflate(R.layout.listview_items, null);
holder = new ViewHolder();
holder.code = (TextView) convertView.findViewById(R.id.textView1);
holder.name = (CheckBox) convertView.findViewById(R.id.checkBox1);
convertView.setTag(holder);
holder.name.setOnClickListener( new View.OnClickListener()
{
public void onClick(View v)
{
CheckBox cb = (CheckBox) v;
ItemVO item = (ItemVO) cb.getTag();
item.setSelected(cb.isChecked());
}
});
}
else
{
holder = (ViewHolder) convertView.getTag();
}
ItemVO state = itemList.get(position);
holder.code.setText(state.getItemdescription());
holder.name.setChecked(state.isSelected());
holder.name.setTag(state);
return convertView;
}
@Override
public Filter getFilter()
{
if (filter == null)
filter = new PkmnNameFilter();
return filter;
}
private class PkmnNameFilter extends Filter
{
@SuppressWarnings("unused")
@SuppressLint("DefaultLocale")
@Override
protected FilterResults performFiltering(CharSequence constraint)
{
FilterResults results = new FilterResults(); // Holds the results of a filtering operation in values
String prefix = constraint.toString().toLowerCase();
if (prefix == null || prefix.length() == 0)
{
ArrayList<ItemVO> list = new ArrayList<ItemVO>(fiems);
results.values = list;
results.count = list.size();
}
else
{
final ArrayList<ItemVO> list = new ArrayList<ItemVO>(fiems);
final ArrayList<ItemVO> nlist = new ArrayList<ItemVO>();
int count = list.size();
for (int i=0; i<count; i++)
{
final ItemVO pkmn = list.get(i);
final String value = pkmn.getItemdescription().toLowerCase();
if (value.startsWith(prefix))
{
nlist.add(pkmn);
}
/*else
{
final Toast toast= Toast.makeText(context, "No Items Found", Toast.LENGTH_SHORT);
toast.show();
Handler handler = new Handler();
handler.postDelayed(new Runnable() {
@Override
public void run() {
toast.cancel();
}
}, 1000);
}*/
}
// set the Filtered result to return
results.values = nlist;
results.count = nlist.size();
}
return results;
}
@SuppressWarnings("unchecked")
@Override
protected void publishResults(CharSequence constraint, FilterResults results) {
itemList = (ArrayList<ItemVO>)results.values; // has the filtered values
clear();
int count = itemList.size();
for (int i=0; i<count; i++)
{
ItemVO pkmn = (ItemVO)itemList.get(i);
add(pkmn);
notifyDataSetChanged(); // notifies the data with new filtered values
}
}
}
public void notifyDataSetChanged() {
super.notifyDataSetChanged();
boolean notifyChanged = true;
}
}
主要活动 for editetxt ..
dataAdapter = new ItemListAdapter(this,R.layout.listview_items, itemList);
lv.setAdapter(dataAdapter);
final EditText searchBox=(EditText) findViewById(R.id.filter_text);
//searchBox.addTextChangedListener(this);
lv.setTextFilterEnabled(true);
// Add Text Change Listener to EditText
searchBox.addTextChangedListener(new TextWatcher() {
@Override
public void onTextChanged(CharSequence cs, int arg1, int arg2, int arg3) {
// Call back the Adapter with current character to Filter
Log.d("Constants.TAG", "*** Search value changed: " + cs.toString());
CateringList.this.dataAdapter.getFilter().filter(cs);
dataAdapter.notifyDataSetChanged();
}
@Override
public void beforeTextChanged(CharSequence arg0, int arg1, int arg2, int arg3) { }
@Override
public void afterTextChanged(Editable arg0) {
//if(arg0.length()==0)
// {
// }
}
});
答案 0 :(得分：1)
如果ArrayList将数据放在你的getView（）方法
中，你只需要验证if (itemList == null || itemList.size() == 0){
//do your code here
holder.code.setText("No Result");
}
兄弟改变了这句话：
clear();
int count = itemList.size();
for (int i=0; i<count; i++)
{
ItemVO pkmn = (ItemVO)itemList.get(i);
add(pkmn);
notifyDataSetChanged();
}
对此：
itemList = (ArrayList<ItemVO>)results.values;
notifyDataSetChanged();
试试这个：
private ArrayList<ItemVO> mItemList;
public Filter getFilter()
{
return new Filter(){
@Override
protected FilterResults performFiltering(CharSequence constraint) {
final FilterResults oResults = new FilterResults();
final ArrayList<ItemVO> result = new ArrayList<ItemVO>();
If (mItemList == null)
mItemList = itemList;
if (constraint != null){
if (mItemList != null && mItemList.size > 0){
//loop
for (final ItemVO item : mItemList){
final String value = item.getItemdescription().toLowerCase();
if (value.startsWith(constraint.toString())){
result.add(item);
}
}
}
}
}
oResults.values = result;
}
@SuppressWarnings("unchecked")
@Override
protected void publishResults(CharSequence constraint,FilterResults results) {
itemList = (ArrayList<ItemVO>)results.values;
notifyDataSetChanged();
}
}
答案 1 :(得分：0)
我不确定我是否可以帮助你。试着改变这个：
CateringList.this.dataAdapter.getFilter().filter(cs);
dataAdapter.notifyDataSetChanged();
你以两种不同的方式访问dataAdapter，而且我认为你不需要在这里调用notifyDataSetChanged，所以改为：
dataAdapter.getFilter().filter(cs);
另外，如果要显示没有结果的列表rty：
dataAdapter.getFilter().filter("");
编辑：
添加此代码以侦听编辑文本更改：
private TextWatcher filterTextWatcher = new TextWatcher() {
public void afterTextChanged(Editable s) {
}
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
}
public void onTextChanged(CharSequence s, int start, int before,
int count) {
Log.d("Constants.TAG", "*** Search value changed: " + cs.toString());
dataAdapter.getFilter().filter(cs);
};
初始化EditText后：
searchBox.addTextChangedListener(filterTextWatcher);
编辑2：
改变这个：
if (prefix == null || prefix.length() == 0)
{
//ArrayList<ItemVO> list = new ArrayList<ItemVO>(fiems);
results.values = null;
results.count = 0;
}
@SuppressWarnings("unchecked")
@Override
protected void publishResults(CharSequence constraint, FilterResults results) {
itemList = (ArrayList<ItemVO>)results.values; // has the filtered values
if(itemList != null) {
clear();
int count = itemList.size();
for (int i=0; i<count; i++)
{
ItemVO pkmn = (ItemVO)itemList.get(i);
add(pkmn);
}
notifyDataSetChanged(); // notifies the data with new filtered values
}
答案 2 :(得分：0)
我已经用这个解决方法解决了......希望这个也适合你：）
searchBox.addTextChangedListener(new TextWatcher() {
@Override
public void onTextChanged(CharSequence cs, int arg1, int arg2, int arg3) {
// Call back the Adapter with current character to Filter
Log.d("Constants.TAG", "*** Search value changed: " + cs.toString());
CateringList.this.dataAdapter.getFilter().filter(cs);
dataAdapter.notifyDataSetChanged();
}
@Override
public void beforeTextChanged(CharSequence arg0, int arg1, int arg2, int arg3) {
dataAdapter.itemList = OriginalItemList;
}
@Override
public void afterTextChanged(Editable arg0) {
//if(arg0.length()==0)
// {
// }
}
});
...只需将原始数据状态分配回适配器以再次过滤。
答案 3 :(得分：0)
这种情况正在发生，因为您的适配器的listItems已被删除，但是当您按退格键时，它们不会被添加回来。例如，当您按下A＆＃39; A＆＃39;时，您在recyclerview中共有10个项目。你得到4个过滤的项目。这里有6个项目从您的实际listItems中删除（之前有10个项目）。但这些被删除的物品从未加回。
<强>解决方案： 检查backpress并在过滤之前，为你创建fullList First的临时副本。并呼叫过滤。
答案 4 :(得分：0)
每次调用onQueryTextChange时，只需将数据刷新到您的recyclerview
@Override
public boolean onQueryTextChange(String newText) {
rvAdapter = new RecyclerViewAdapter(Context, <list of files>);
recyclerView.setAdapter(rvAdapter);
rvAdapter.getFilter().filter(newText);
return true;
}