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问题描述
我有一个自定义列表视图适配器正在加载联系人列表.当我打开应用程序时，联系人正在完美加载，但是一旦滚动到首选项片段"后回来，列表视图为空.虽然数据是通过调用内部类LoadContact来收集的，但列表视图中没有任何内容.有三个片段.请指导.片段代码(tab1).如果您看到我在oncreatview中添加了适配器初始化，否则在后选项卡上我得到了Null point异常.我在这里纠正了吗?
I have one custom list view adapter loading contact list. When I open app, contacts are loading perfectly , but once I came back after scrolling to Preference Fragment, listview is empty. Though Data is collected by calling Inner class LoadContact but nothing in listview. There are three fragments. pls guide.Code for Fragment (tab1). If u see I added adapter initialization in oncreatview as otherwise on back tab I m getting Null point exception. m I did correct here?
public class Requestor extends Fragment {
EditText targetdevice;
ListView recentlist;
List<String> recentlistarray = new ArrayList<>();
ArrayAdapter arrayAdapter;
Dialog dialog;
String targetmobile, requesttype;
private TextView tex1, remotelocation;
int deviceid;
LinearLayout contactlayout;
RadioButton radiorecent, radiocontact;
ArrayList<ContactListSelectUser> contactListSelectUsers;
List<ContactListSelectUser> temp;
// Contact List
ListView listView;
// Cursor to load contacts list
Cursor phones, email;
// Pop up
ContentResolver resolver;
SearchView search;
ContactListAdapter adapter;
@Override
public void onActivityCreated(@Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
LoadContact loadContact = new LoadContact();
loadContact.execute();
}
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) throws NullPointerException{
View view = inflater.inflate(R.layout.autolocationrequester, container, false);
targetdevice = (EditText) view.findViewById(R.id.targetdevice);
recentlist = (ListView) view.findViewById(R.id.targetlist);
remotelocation = (TextView) view.findViewById(R.id.remotelocationreq);
tex1 = (TextView) view.findViewById(R.id.tex1);
requesttype = "Location";
radiorecent = (RadioButton) view.findViewById(R.id.radiorecent);
radiocontact = (RadioButton) view.findViewById(R.id.radiocontact);
contactlayout = (LinearLayout) view.findViewById(R.id.contactlayout);
tex1 = (TextView) view.findViewById(R.id.tex1);
recentlist.setVisibility(View.GONE);
contactlayout.setVisibility(View.GONE);
tex1.setVisibility(View.GONE);
contactListSelectUsers = new ArrayList<ContactListSelectUser>();
resolver = getActivity().getApplicationContext().getContentResolver();
listView = (ListView) view.findViewById(R.id.contacts_list);
adapter = new ContactListAdapter(contactListSelectUsers, getActivity().getApplicationContext());
phones = getActivity().getApplicationContext().getContentResolver().query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null, null, null, ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME + " ASC");
LoadContact loadContact = new LoadContact();
loadContact.execute();
search = (SearchView) view.findViewById(R.id.searchView);
//*** setOnQueryTextListener ***
search.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
@Override
public boolean onQueryTextSubmit(String query) {
// TODO Auto-generated method stub
return false;
}
@Override
public boolean onQueryTextChange(String newText) {
// TODO Auto-generated method stub
adapter.filter(newText);
return false;
}
});
SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(getActivity().getApplicationContext());
deviceid = Integer.parseInt(sharedPreferences.getString("deviceid", ""));
remotelocation.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
arrayAdapter = new ArrayAdapter(getActivity().getApplicationContext(), android.R.layout.simple_list_item_1, recentlistarray);
recentlist.setAdapter(arrayAdapter);
targetmobile = targetdevice.getText().toString();
new sendreqloc().execute();
targetdevice.setText("");
// Popup.smallpopup("hi", getApplicationContext());
}
});
radiorecent.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
recentlist.setVisibility(View.VISIBLE);
tex1.setVisibility(View.VISIBLE);
contactlayout.setVisibility(View.GONE);
targetdevice.setText("");
}
});
radiocontact.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
recentlist.setVisibility(View.GONE);
contactlayout.setVisibility(View.VISIBLE);
tex1.setVisibility(View.GONE);
targetdevice.setText("");
LoadContact loadContact = new LoadContact();
loadContact.execute();
}
});
return view;
}
public class LoadContact extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
super.onPreExecute();
}
@Override
protected Void doInBackground(Void... voids) {
// Get Contact list from Phone
if (phones != null) {
Log.e("count", "" + phones.getCount());
if (phones.getCount() == 0) {
// Toast.makeText(Requestor.this, "No contacts in your contact list.", Toast.LENGTH_LONG).show();
}
while (phones.moveToNext()) {
Log.d("Contact Class Called","");
Bitmap bit_thumb = null;
String id = phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.CONTACT_ID));
String name = phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));
String phoneNumber = phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));
// String EmailAddr = phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Email.DATA2));
String image_thumb = phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.PHOTO_THUMBNAIL_URI));
try {
if (image_thumb != null) {
bit_thumb = MediaStore.Images.Media.getBitmap(resolver, Uri.parse(image_thumb));
} else {
Log.e("No Image Thumb", "--------------");
}
} catch (IOException e) {
e.printStackTrace();
}
ContactListSelectUser contactListSelectUser = new ContactListSelectUser();
contactListSelectUser.setThumb(bit_thumb);
contactListSelectUser.setName(name);
contactListSelectUser.setPhone(phoneNumber);
contactListSelectUser.setEmail(id);
// contactListSelectUser.setCheckedBox(false);
// if (!contactListSelectUsers.contains(contactListSelectUser.getPhone())) {
contactListSelectUsers.add(contactListSelectUser);
//}
}
} else {
Log.e("Cursor close 1", "----------------");
}
//phones.close();
//System.out.println(contactListSelectUsers.size());
return null;
}
@Override
protected void onPostExecute(Void aVoid) {
super.onPostExecute(aVoid);
adapter = new ContactListAdapter(contactListSelectUsers, getActivity());
listView.setAdapter(adapter);
// Select item on listclick
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
Log.e("search", "here---------------- listener");
ContactListSelectUser data = contactListSelectUsers.get(i);
targetdevice.setText(data.getPhone());
}
});
listView.setFastScrollEnabled(true);
}
}
/* @Override
protected void onStop() {
super.onStop();
phones.close();
}*/
}
自定义适配器类代码:
public class ContactListAdapter extends BaseAdapter implements Filterable {
public List<ContactListSelectUser> _data;
private ArrayList<ContactListSelectUser> arraylist;
Context _c;
ViewHolder v;
RoundImage roundedImage;
private Filter filter = new CustomFilter();
public ContactListAdapter(List<ContactListSelectUser> contactListSelectUsers, Context context) {
_data = contactListSelectUsers;
_c = context;
this.arraylist = new ArrayList<ContactListSelectUser>();
this.arraylist.addAll(_data);
}
@Override
public int getCount() {
return _data.size();
}
@Override
public Object getItem(int i) {
return _data.get(i);
}
@Override
public long getItemId(int i) {
return i;
}
@TargetApi(Build.VERSION_CODES.LOLLIPOP)
@Override
public View getView(int i, View convertView, ViewGroup viewGroup) {
View view = convertView;
if (view == null) {
LayoutInflater li = (LayoutInflater) _c.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = li.inflate(R.layout.contact_info, null);
Log.e("Inside", "here--------------------------- In view1");
} else {
view = convertView;
Log.e("Inside", "here--------------------------- In view2");
}
v = new ViewHolder();
v.title = (TextView) view.findViewById(R.id.name);
// v.check = (CheckBox) view.findViewById(R.id.check);
v.phone = (TextView) view.findViewById(R.id.no);
v.imageView = (ImageView) view.findViewById(R.id.pic);
final ContactListSelectUser data = (ContactListSelectUser) _data.get(i);
v.title.setText(data.getName());
// v.check.setChecked(data.getCheckedBox());
v.phone.setText(data.getPhone());
// Set image if exists
try {
if (data.getThumb() != null) {
v.imageView.setImageBitmap(data.getThumb());
} else {
v.imageView.setImageResource(R.mipmap.ic_launcher);
}
// Seting round image
Bitmap bm = BitmapFactory.decodeResource(view.getResources(), R.mipmap.ic_launcher); // Load default image
roundedImage = new RoundImage(bm);
v.imageView.setImageDrawable(roundedImage);
} catch (OutOfMemoryError e) {
// Add default picture
v.imageView.setImageDrawable(this._c.getDrawable(R.mipmap.ic_launcher));
e.printStackTrace();
}
Log.e("Image Thumb", "--------------" + data.getThumb());
/*// Set check box listener android
v.check.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
CheckBox checkBox = (CheckBox) view;
if (checkBox.isChecked()) {
data.setCheckedBox(true);
} else {
data.setCheckedBox(false);
}
}
});*/
view.setTag(data);
return view;
}
// Filter Class
public void filter(String charText) {
charText = charText.toLowerCase(Locale.getDefault());
_data.clear();
if (charText.length() == 0) {
_data.addAll(arraylist);
} else {
for (ContactListSelectUser wp : arraylist) {
if (wp.getName().toLowerCase(Locale.getDefault())
.contains(charText)) {
_data.add(wp);
}
}
}
notifyDataSetChanged();
}
@Override
public Filter getFilter() {
return filter;
}
static class ViewHolder {
ImageView imageView;
TextView title, phone;
CheckBox check;
}
private class CustomFilter extends Filter {
@Override
protected FilterResults performFiltering(CharSequence charSequence) {
_data.clear();
FilterResults filterResults = new FilterResults();
filterResults.values = _data;
filterResults.count = _data.size();
return filterResults;
}
@Override
protected void publishResults(CharSequence charSequence, FilterResults filterResults) {
if (filterResults.count > 0) {
notifyDataSetChanged();
} else {
notifyDataSetInvalidated();
}
}
}
}
下面是logcat，您可以在其中选择后退片段但未设置为listview的情况下看到数据已提取.
below is logcat where u can see data is fetched while I choose back fragment but not set to listview.
E/Inside: here--------------------------- In view1
E/Image Thumb: --------------null
E/Inside: here--------------------------- In view1
E/Image Thumb: --------------null
I/TextInputLayout: EditText added is not a TextInputEditText. Please switch to using that class instead.
E/count: 2
E/No Image Thumb: --------------
E/No Image Thumb: --------------
E/count: 2
E/count: 2
推荐答案
我现在解决了.问题仅在于将搜索视图代码放置在点击侦听器上的radiocontact中，而不是直接放置在createview方法中.
I solved it now. The issue was only placing search view code in radiocontact on click listeners instead of in createview method directly.
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