In my android project i have a listview with items loaded from an online database. When i click on an item i go to another class where i can delete or update it. My problem is that when i press the back button, my listview is empty. I tried onBackPressed with intent to go to previous activity but it is empty again. I want to reload my listview when from a clicked item i press the back button. Below is my code.
The listview:
public class AllStudents extends AppCompatActivity {
ListView StudentListView;
ProgressBar progressBar;
String HttpUrl = "http://sissy-nickels.000webhostapp.com/AllStudentData.php";
List<String> IdList = new ArrayList<>();
String LessonName;
HttpParse httpParse = new HttpParse();
ProgressDialog pDialog;
String FinalJSonObject;
HashMap<String,String> ResultHash = new HashMap<>();
String ParseResult ;
List<Student> studentList;
EditText search;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_allstudents);
StudentListView = (ListView)findViewById(R.id.listview2);
progressBar = (ProgressBar)findViewById(R.id.progressBar);
LessonName = getIntent().getStringExtra("Lesson");
HttpWebCall(LessonName);
//Adding ListView Item click Listener.
StudentListView.setOnItemClickListener(new AdapterView.OnItemClickListener()
{
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
// TODO Auto-generated method stub
Intent intent = new Intent(AllStudents.this,SingleStudent.class);
// Sending ListView clicked value using intent.
intent.putExtra("ListViewValue", IdList.get(position).toString());
startActivity(intent);
//Finishing current activity after open next activity.
//finish();
}
});
search = (EditText)findViewById(R.id.search);
search.addTextChangedListener(new TextWatcher() {
#Override
public void beforeTextChanged (CharSequence s, int start, int count, int after) {
}
// when text is entered in search box, filter list by search text
#Override
public void onTextChanged(CharSequence cs, int start, int before, int count) {
filterStudents(cs);
}
#Override
public void afterTextChanged(Editable s) {
}
});
// check student's name whether contain text entered in search box
}
public void HttpWebCall(final String LessonName){
class HttpWebCallFunction extends AsyncTask<String,Void,String> {
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = ProgressDialog.show(AllStudents.this,"Loading Data",null,true,true);
}
#Override
protected void onPostExecute(String httpResponseMsg) {
super.onPostExecute(httpResponseMsg);
pDialog.dismiss();
//Storing Complete JSon Object into String Variable.
FinalJSonObject = httpResponseMsg ;
//Parsing the Stored JSOn String to GetHttpResponse Method.
new GetHttpResponse(AllStudents.this).execute();
}
#Override
protected String doInBackground(String... params) {
ResultHash.put("LessonName",params[0]);
ParseResult = httpParse.postRequest(ResultHash, HttpUrl);
return ParseResult;
}
}
HttpWebCallFunction httpWebCallFunction = new HttpWebCallFunction();
httpWebCallFunction.execute(LessonName);
}
// JSON parse class started from here.
private class GetHttpResponse extends AsyncTask<Void, Void, Void>
{
public Context context;
public GetHttpResponse(Context context)
{
this.context = context;
}
#Override
protected void onPreExecute()
{
super.onPreExecute();
}
#Override
protected Void doInBackground(Void... arg0)
{
try
{
if(FinalJSonObject != null)
{
JSONArray jsonArray = null;
try {
jsonArray = new JSONArray(FinalJSonObject);
JSONObject jsonObject;
Student student;
studentList = new ArrayList<Student>();
for(int i=0; i<jsonArray.length(); i++)
{
jsonObject = jsonArray.getJSONObject(i);
student = new Student();
// Adding Student Id TO IdList Array.
IdList.add(jsonObject.getString("id").toString());
//Adding Student Name.
student.StudentName = jsonObject.getString("Regnum").toString();
studentList.add(student);
}
}
catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
catch (Exception e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(Void result)
{
progressBar.setVisibility(View.GONE);
StudentListView.setVisibility(View.VISIBLE);
ListAdapter adapter = new ListAdapter(studentList, context);
StudentListView.setAdapter(adapter);
adapter.notifyDataSetChanged();
}
}
private void filterStudents (CharSequence cs) {
List<Student> filteredList = new ArrayList<>();
if (TextUtils.isEmpty(cs)) {
// no text is entered for search, do nothing
return;
}
// build new student list which filtered by search text.
for (Student student : studentList) {
if (student.StudentName.contains(cs)) {
filteredList.add(student);
}
}
// show filtered list in listview
ListAdapter adapter = new ListAdapter(filteredList, this);
StudentListView.setAdapter(adapter);
adapter.notifyDataSetChanged();
}}
And the code from item click:
public class SingleStudent extends AppCompatActivity {
HttpParse httpParse = new HttpParse();
ProgressDialog pDialog;
// Http Url For Filter Student Data from Id Sent from previous activity.
String HttpURL = "http://sissy-nickels.000webhostapp.com/FilterStudentData.php";
// Http URL for delete Already Open Student Record.
String HttpUrlDeleteRecord = "http://sissy-nickels.000webhostapp.com/DeleteStudent.php";
String finalResult ;
HashMap<String,String> hashMap = new HashMap<>();
String ParseResult ;
HashMap<String,String> ResultHash = new HashMap<>();
String FinalJSonObject ;
TextView NAME,SURNAME,DEPT,REGNUM,GRADE;
String NameHolder, SurnameHolder, DeptHolder, RegnumHolder, GradeHolder;
Button UpdateButton, DeleteButton;
String TempItem;
ProgressDialog progressDialog2;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_singlestudent);
NAME = (TextView)findViewById(R.id.name);
SURNAME = (TextView)findViewById(R.id.surname);
DEPT = (TextView)findViewById(R.id.dept);
REGNUM = (TextView)findViewById(R.id.regnum);
GRADE = (TextView)findViewById(R.id.grade);
UpdateButton = (Button)findViewById(R.id.BDel);
DeleteButton = (Button)findViewById(R.id.BUp);
//Receiving the ListView Clicked item value send by previous activity.
TempItem = getIntent().getStringExtra("ListViewValue");
//Calling method to filter Student Record and open selected record.
HttpWebCall(TempItem);
UpdateButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(SingleStudent.this,StudentUpdate.class);
// Sending Student Id, Name, Number and Class to next UpdateActivity.
intent.putExtra("Id", TempItem);
intent.putExtra("name", NameHolder);
intent.putExtra("surname", SurnameHolder);
intent.putExtra("dept", DeptHolder);
intent.putExtra("regnum", RegnumHolder);
intent.putExtra("grade", GradeHolder);
startActivity(intent);
// Finishing current activity after opening next activity.
finish();
}
});
// Add Click listener on Delete button.
DeleteButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
// Calling Student delete method to delete current record using Student ID.
StudentDelete(TempItem);
}
});
}
// Method to Delete Student Record
public void StudentDelete(final String StudentID) {
class StudentDeleteClass extends AsyncTask<String, Void, String> {
#Override
protected void onPreExecute() {
super.onPreExecute();
progressDialog2 = ProgressDialog.show(SingleStudent.this, "Φόρτωση", null, true, true);
}
#Override
protected void onPostExecute(String httpResponseMsg) {
super.onPostExecute(httpResponseMsg);
progressDialog2.dismiss();
Toast.makeText(SingleStudent.this, httpResponseMsg.toString(), Toast.LENGTH_LONG).show();
finish();
}
#Override
protected String doInBackground(String... params) {
// Sending STUDENT id.
hashMap.put("StudentID", params[0]);
finalResult = httpParse.postRequest(hashMap, HttpUrlDeleteRecord);
return finalResult;
}
}
StudentDeleteClass studentDeleteClass = new StudentDeleteClass();
studentDeleteClass.execute(StudentID);
}
//Method to show current record Current Selected Record
public void HttpWebCall(final String PreviousListViewClickedItem){
class HttpWebCallFunction extends AsyncTask<String,Void,String> {
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = ProgressDialog.show(SingleStudent.this,"Φόρτωση",null,true,true);
}
#Override
protected void onPostExecute(String httpResponseMsg) {
super.onPostExecute(httpResponseMsg);
pDialog.dismiss();
//Storing Complete JSon Object into String Variable.
FinalJSonObject = httpResponseMsg ;
//Parsing the Stored JSOn String to GetHttpResponse Method.
new GetHttpResponse(SingleStudent.this).execute();
}
#Override
protected String doInBackground(String... params) {
ResultHash.put("StudentID",params[0]);
ParseResult = httpParse.postRequest(ResultHash, HttpURL);
return ParseResult;
}
}
HttpWebCallFunction httpWebCallFunction = new HttpWebCallFunction();
httpWebCallFunction.execute(PreviousListViewClickedItem);
}
// Parsing Complete JSON Object.
private class GetHttpResponse extends AsyncTask<Void, Void, Void>
{
public Context context;
public GetHttpResponse(Context context)
{
this.context = context;
}
#Override
protected void onPreExecute()
{
super.onPreExecute();
}
#Override
protected Void doInBackground(Void... arg0)
{
try
{
if(FinalJSonObject != null)
{
JSONArray jsonArray = null;
try {
jsonArray = new JSONArray(FinalJSonObject);
JSONObject jsonObject;
for(int i=0; i<jsonArray.length(); i++)
{
jsonObject = jsonArray.getJSONObject(i);
// Storing Student Name, Phone Number, Class into Variables.
NameHolder = jsonObject.getString("Name").toString() ;
SurnameHolder = jsonObject.getString("Surname").toString() ;
DeptHolder = jsonObject.getString("Dept").toString() ;
RegnumHolder = jsonObject.getString("Regnum").toString() ;
GradeHolder = jsonObject.getString("Grade").toString() ;
}
}
catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
catch (Exception e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(Void result)
{
// Setting Student Name, Phone Number, Class into TextView after done all process .
NAME.setText(NameHolder);
SURNAME.setText(SurnameHolder);
DEPT.setText(DeptHolder);
REGNUM.setText(RegnumHolder);
GRADE.setText(GradeHolder);
}
}}
Than you in advance!
try this on AllStudents activity
#Override
protected void onResume() {
super.onResume();
if (studentList != null && studentList.size()>0) {
ListAdapter adapter = new ListAdapter(studentList, this);
StudentListView.setAdapter(adapter);
adapter.notifyDataSetChanged();
}
}
*Note
when you make a search you run the filterStudents() method
and replace the current list in the adapter
ListAdapter adapter = new ListAdapter(filteredList, this);
but make sure that if you search for nothing .. return the original list
ListAdapter adapter = new ListAdapter(studentList, this);
or you will get an empty list view
You should not recreate from secondActivity. You just finish it when your work is done in secondActivity. Which means, simply you have to do the below in your secondActivity.
#Override
public void onBackPressed() {
super.onBackPressed();
}
Related
sort ListView Android by float number ...
I have a listview price type float display of a mysql database ,,
I want to sort it (by order) but I have not found a solution ..
how can I do it please !!!
it's the code of my listView with prices done !!
private class GetHttpResponse extends AsyncTask<Void, Void, Void>{
public Context context;
String ResultHolder;
List<subjects> subjectsList;
public GetHttpResponse(Context context)
{
this.context = context;
}
#Override
protected void onPreExecute()
{
super.onPreExecute();
}
#Override
protected Void doInBackground(Void... arg0)
{
HttpServicesClass httpServiceObject = new
HttpServicesClass(ServerURL);
try
{
httpServiceObject.ExecutePostRequest();
if(httpServiceObject.getResponseCode() == 200)
{
ResultHolder = httpServiceObject.getResponse();
if(ResultHolder != null)
{
JSONArray jsonArray = null;
try {
jsonArray = new JSONArray(ResultHolder);
JSONObject jsonObject;
subjects subjects;
subjectsList = new ArrayList<subjects>();
for(int i=0; i<jsonArray.length(); i++)
{ subjects = new subjects();
jsonObject = jsonArray.getJSONObject(i);
subjects.SubjectName = jsonObject.getString("tarif");
subjectsList.add(subjects);
} }
catch (JSONException e) {
e.printStackTrace();
} } } else
{
Toast.makeText(context, httpServiceObject.getErrorMessage(),
Toast.LENGTH_SHORT).show();
}
}
catch (Exception e)
{
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(Void result)
{ progressBarSubject.setVisibility(View.GONE);
SubjectListView.setVisibility(View.VISIBLE);
if(subjectsList != null)
{
ListAdapterClass adapter = new ListAdapterClass(subjectsList,
context);
SubjectListView.setAdapter(adapter);
SubjectListView.setOnItemClickListener(new
AdapterView.OnItemClickListener(){
#Override
public void onItemClick(AdapterView<?> parent, View view,
int pos, long id) {
String selectedItem =
parent.getItemAtPosition(pos).toString();
Toast.makeText(TechnicienActivity.this,selectedItem,
Toast.LENGTH_SHORT).show();
Intent intent = new
Intent(getApplicationContext(),Main2Activity.class);
intent.putExtra("Position" , String.valueOf(id));
startActivity(intent);
} }); } } }
You can sort the list by using
Collections.sort(list);
and then set this to the listview.
Example;
subjectsList.add(subjects);
Collections.sort(subjectsList);
Im developing an android app that performs add, update, and delete operations on data on a localhosted MySQL Database. Everything is working fine except for the update part. It happens on the activity ViewFeedingSched when im trying to update the data. The app crashes when the update button is pressed or simply when the function for updating is called. The logcat is giving a message: threadid=1: thread exiting with uncaught exception (group=0x41640c80) . I've seen several solutions and they're mostly about not initializing some objects or having null values. I can't seem to find where I have not initialized something. It was working before and I don't know what I've changed with the program. Below is the codes of the ViewFeedingSched class.
EDIT
I've added the codes for the class that goes before the ViewFeedingSched class which is the FeedingSchedList class. It's layout contains a ListView with the data being listed, and an onItemClick method that opens the ViewFeedingSched class whenever an item (data) is clicked.
public class ViewFeedingSched extends AppCompatActivity implements View.OnClickListener {
private EditText editTextSchedNo;
private EditText editTextFeedTime;
private EditText editTextFeedAmt;
private TextView textViewCurrentTimeSet;
private TextView textViewIDSelected;
//private TextView textViewCurrentAmtSet;
private NumberPicker numPickerHr;
private NumberPicker numPickerMin;
//private Spinner spinnerFeedAmt;
ArrayAdapter<CharSequence> adapter;
private Button buttonUpdate;
private Button buttonDelete;
private String id;
private String ftime;
// private String famt;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.view_feeding_sched);
Intent intent = getIntent();
id = intent.getStringExtra(Config.SCHED_ID);
ftime = intent.getStringExtra(Config.FEEDTIME);
//famt = intent.getStringExtra(Config.FEEDAMT);
editTextSchedNo = (EditText) findViewById(R.id.ET_SchedNo);
editTextFeedTime = (EditText) findViewById(R.id.ET_FeedTime);
//editTextFeedAmt = (EditText) findViewById(R.id.ET_FeedAmt);
textViewCurrentTimeSet = (TextView) findViewById(R.id.TV_CurrentTimeSet);
textViewIDSelected = (TextView) findViewById(R.id.TV_PickedSchedID);
//textViewCurrentAmtSet = (TextView) findViewById(R.id.TV_CurrentAmountSet);
buttonUpdate = (Button) findViewById(R.id.BT_UpdateSched);
buttonDelete = (Button) findViewById(R.id.BT_DeleteSched);
buttonUpdate.setOnClickListener(this);
buttonDelete.setOnClickListener(this);
textViewIDSelected.setText(id);
textViewCurrentTimeSet.setText(ftime);
//textViewCurrentAmtSet.setText(famt);
numPickerHr = (NumberPicker) findViewById(R.id.NP_Hour);
numPickerHr.setMinValue(0);
numPickerHr.setMaxValue(23);
numPickerHr.setWrapSelectorWheel(true);
numPickerMin = (NumberPicker) findViewById(R.id.NP_Min);
numPickerMin.setMinValue(0);
numPickerMin.setMaxValue(59);
numPickerMin.setWrapSelectorWheel(true);
//spinnerFeedAmt = (Spinner) findViewById(R.id.SP_FeedAmt);
//adapter = ArrayAdapter.createFromResource(this,R.array.FeedAmt,android.R.layout.simple_spinner_item);
//spinnerFeedAmt.setAdapter(adapter);
getSchedule();
}
private void getSchedule(){
class GetSchedule extends AsyncTask<Void,Void,String>{
ProgressDialog loading;
#Override
protected void onPreExecute() {
super.onPreExecute();
loading = ProgressDialog.show(ViewFeedingSched.this,"Fetching...","Wait...",false,false);
}
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
loading.dismiss();
showSchedule(s);
}
#Override
protected String doInBackground(Void... params) {
RequestHandler rh = new RequestHandler();
String s = rh.sendGetRequestParam(Config.URL_GET_SCHED,id);
return s;
}
}
GetSchedule ge = new GetSchedule();
ge.execute();
}
private void showSchedule(String json){
try {
JSONObject jsonObject = new JSONObject(json);
JSONArray result = jsonObject.getJSONArray(Config.TAG_JSON_ARRAY);
JSONObject c = result.getJSONObject(0);
String feedtime = c.getString(Config.TAG_FEEDTIME);
String feedamt = c.getString(Config.TAG_FEEDAMT);
//editTextFeedTime.setText(feedtime);
// editTextFeedAmt.setText(feedamt);
textViewCurrentTimeSet.setText(feedtime);
// String spinnerVal = String.valueOf(spinnerFeedAmt.getSelectedItem().toString());
} catch (JSONException e) {
e.printStackTrace();
}
}
private void updateSchedule(){
final String feedtime = editTextFeedTime.getText().toString().trim();
final String feedamt = editTextFeedAmt.getText().toString().trim();
final String NP_FeedTime_HR = String.valueOf(numPickerHr.getValue()).trim();
final String NP_FeedTime_MIN = String.valueOf(numPickerMin.getValue()).trim();
//final String SP_FeedAmt = spinnerFeedAmt.getSelectedItem().toString().trim();
class UpdateSchedule extends AsyncTask<Void,Void,String>{
ProgressDialog loading;
#Override
protected void onPreExecute() {
super.onPreExecute();
loading = ProgressDialog.show(ViewFeedingSched.this,"Updating...","Wait...",false,false);
}
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
loading.dismiss();
Toast.makeText(ViewFeedingSched.this,s,Toast.LENGTH_LONG).show();
}
#Override
protected String doInBackground(Void... params) {
HashMap<String,String> hashMap = new HashMap<>();
hashMap.put(Config.KEY_SCHED_ID,id);
hashMap.put(Config.KEY_FEED_TIME,NP_FeedTime_HR+":"+NP_FeedTime_MIN+":00");
hashMap.put(Config.KEY_FEED_AMT,feedamt);
RequestHandler rh = new RequestHandler();
String s = rh.sendPostRequest(Config.URL_UPDATE_SCHED,hashMap);
return s;
}
}
UpdateSchedule ue = new UpdateSchedule();
ue.execute();
}
private void deleteSchedule(){
class DeleteSchedule extends AsyncTask<Void,Void,String> {
ProgressDialog loading;
#Override
protected void onPreExecute() {
super.onPreExecute();
loading = ProgressDialog.show(ViewFeedingSched.this, "Updating...", "Wait...", false, false);
}
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
loading.dismiss();
Toast.makeText(ViewFeedingSched.this, s, Toast.LENGTH_LONG).show();
}
#Override
protected String doInBackground(Void... params) {
RequestHandler rh = new RequestHandler();
String s = rh.sendGetRequestParam(Config.URL_DELETE_SCHED, id);
return s;
}
}
DeleteSchedule de = new DeleteSchedule();
de.execute();
}
private void confirmDeleteSchedule(){
AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(this);
alertDialogBuilder.setMessage("Are you sure you want to delete this schedule?");
alertDialogBuilder.setPositiveButton("Yes",
new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface arg0, int arg1) {
deleteSchedule();
startActivity(new Intent(ViewFeedingSched.this,FeedingScheduleList.class));
}
});
alertDialogBuilder.setNegativeButton("No",
new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface arg0, int arg1) {
}
});
AlertDialog alertDialog = alertDialogBuilder.create();
alertDialog.show();
}
#Override
public void onClick(View v) {
if(v == buttonUpdate){
updateSchedule();
}
if(v == buttonDelete){
confirmDeleteSchedule();
}
}
}
FeedingSchedList class
public class FeedingScheduleList extends AppCompatActivity implements ListView.OnItemClickListener{
private ListView listView;
private String JSON_STRING;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.feeding_schedule_list);
listView = (ListView) findViewById(R.id.FeedSchedListView);
listView.setOnItemClickListener(this);
getJSON();
}
private void showFeedSched(){
JSONObject jsonObject = null;
ArrayList<HashMap<String,String>> list = new ArrayList<HashMap<String, String>>();
try {
jsonObject = new JSONObject(JSON_STRING);
JSONArray result = jsonObject.getJSONArray(Config.TAG_JSON_ARRAY);
for(int i = 0; i<result.length(); i++){
JSONObject jo = result.getJSONObject(i);
String id = jo.getString(Config.TAG_ID);
String feedtime = jo.getString(Config.TAG_FEEDTIME);
String feedamt = jo.getString(Config.TAG_FEEDAMT);
HashMap<String,String> schedules = new HashMap<>();
schedules.put(Config.TAG_ID,id+" ");
schedules.put(Config.TAG_FEEDTIME,feedtime+" ");
schedules.put(Config.TAG_FEEDAMT,feedamt+" ");
list.add(schedules);
}
} catch (JSONException e) {
e.printStackTrace();
}
ListAdapter adapter = new SimpleAdapter(
FeedingScheduleList.this, list, R.layout.list_item,
new String[]{Config.TAG_ID,Config.TAG_FEEDTIME,Config.TAG_FEEDAMT},
new int[]{R.id.SchedID, R.id.FeedSchedTime,R.id.FeedAmt});
listView.setAdapter(adapter);
}
private void getJSON() {
class GetJSON extends AsyncTask<Void, Void, String> {
ProgressDialog loading;
#Override
protected void onPreExecute() {
super.onPreExecute();
loading = ProgressDialog.show(FeedingScheduleList.this, "Fetching Data", "Wait...", false, false);
}
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
loading.dismiss();
JSON_STRING = s;
showFeedSched();
}
#Override
protected String doInBackground(Void... params) {
RequestHandler rh = new RequestHandler();
String s = rh.sendGetRequest(Config.URL_GET_ALL);
return s;
}
}
GetJSON gj = new GetJSON();
gj.execute();
}
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Intent intent = new Intent(this, ViewFeedingSched.class);
HashMap<String,String> map =(HashMap)parent.getItemAtPosition(position);
String schedID = map.get(Config.TAG_ID).toString();
String feedTime = map.get(Config.TAG_FEEDTIME).toString();
//String feedAmt = map.get(Config.TAG_FEEDAMT).toString();
intent.putExtra(Config.SCHED_ID,schedID);
intent.putExtra(Config.FEEDTIME,feedTime);
//intent.putExtra(Config.FEEDAMT,feedAmt);
startActivity(intent);
}
}
I have my class that is based on a tutorial online, i dont fully understand it yet ( working on it ), but its working.
It populates the listview, now i want to get the id and show the data related to that id on a more detailed activity.
I already obtain the id of the item i am clicking:
list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> arg0, View view, int position,
long id) {
Log.e("item clicks", "selected: " + position);
}
});
But now, i am not getting how i will do this, get the data of the position i clicked.
I have a inner class "GetObras" but i cant use the variables from it on my onCreate, i tried make them global, etc
public class MainActivity extends ActionBarActivity implements SearchView.OnQueryTextListener{
private String TAG = MainActivity.class.getSimpleName();
private ProgressDialog pDialog;
private ListView list;
private static String url = "http://ploran.gear.host/scriptobras6.php";
ArrayList<HashMap<String, String>> obrasList;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
obrasList = new ArrayList<HashMap<String, String>>();
list = (ListView)findViewById(R.id.list1);
new GetObras().execute();
list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> arg0, View view, int position,
long id) {
Log.e("item clicks", "selected: " + position);
}
});
}
private class GetObras extends AsyncTask<Void, Void, Void> {
#Override
protected void onPreExecute() {
super.onPreExecute();
// Showing progress dialog
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Please wait...");
pDialog.setCancelable(false);
pDialog.show();
}
#Override
protected Void doInBackground(Void... arg0) {
HttpHandler sh = new HttpHandler();
// Making a request to url and getting response
String jsonStr = sh.makeServiceCall(url);
Log.e(TAG, "Response from url: " + jsonStr);
if (jsonStr != null) {
try {
//JSONObject jsonObj = new JSONObject(jsonStr);
JSONArray obras = new JSONArray(jsonStr);
// Getting JSON Array node
//JSONArray obras = jsonObj.getJSONArray("obras");
// looping through All
for (int i = 0; i < obras.length(); i++) {
JSONObject c = obras.getJSONObject(i);
String id = c.getString("Id");
String nomeObra = c.getString("NomeObra");
String idCliente = c.getString("idCliente");
String DataLevantamento = c.getString("DataPLevantamento");
String DataRealizacao = c.getString("DataRLevantamento");
String Estado = c.getString("Estado");
String DataMateriais = c.getString("DataRMateriais");
String DataInicioObra = c.getString("DataInicioObra");
String DataConclusao = c.getString("DataConclusao");
String DataVestoria = c.getString("DataVestoria");
String Obs = c.getString("Obs");
String Prompor = c.getString("Prompor");
String Levantpor = c.getString("Levantpor");
String executpor = c.getString("executpor");
// tmp hash map for single contact
HashMap<String, String> obra = new HashMap<>();
// adding each child node to HashMap key => value
obra.put("Id", id);
obra.put("nomeObra", nomeObra);
obra.put("idCliente", idCliente);
obra.put("DataLevantamento", DataLevantamento);
obra.put("DataRealizacao", DataRealizacao);
obra.put("Estado", Estado);
obra.put("DataMateriais", DataMateriais);
obra.put("DataIncioObra", DataInicioObra);
obra.put("DataConclusao", DataConclusao);
obra.put("DataVestoria", DataVestoria);
obra.put("Obs", Obs);
obra.put("Prompor", Prompor);
obra.put("Levantpor", Levantpor);
obra.put("executpor", executpor);
// adding contact to contact list
obrasList.add(obra);
}
} catch (final JSONException e) {
Log.e(TAG, "Json parsing error: " + e.getMessage());
runOnUiThread(new Runnable() {
#Override
public void run() {
Toast.makeText(getApplicationContext(),
"Json parsing error: " + e.getMessage(),
Toast.LENGTH_LONG)
.show();
}
});
}
} else {
Log.e(TAG, "Couldn't get json from server.");
runOnUiThread(new Runnable() {
#Override
public void run() {
Toast.makeText(getApplicationContext(),
"Couldn't get json from server. Check LogCat for possible errors!",
Toast.LENGTH_LONG)
.show();
}
});
}
return null;
}
#Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
// Dismiss the progress dialog
if (pDialog.isShowing())
pDialog.dismiss();
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(
MainActivity.this, obrasList,
R.layout.list_item, new String[]{"nomeObra", "idCliente",
"Estado"}, new int[]{R.id.name,
R.id.email, R.id.mobile});
list.setAdapter(adapter);
}
}
List<String> cities;
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menu_search, menu);
MenuItem searchItem = menu.findItem(R.id.search);
return true;
}
#Override
public boolean onQueryTextSubmit(String query) {
// User pressed the search button
return false;
}
#Override
public boolean onQueryTextChange(String newText) {
// User changed the text
return false;
}
}
If what i think is correct, i could just get the JsonArray from the doInBackground method in GetObras and do:
JSONObject c = obras.getJSONObject(position);
Thank you.
You can retrieve it using obrasList reference. As your are passing obrasList to your adapter.
Below is the sample code:
obrasList.get(position).get(yourkey);
Hope this will help you.. :))
I want to print an ArrayList. I have receive value arraylist from class AsyncTask, in MainActivity, I have value ArrayList, but when I print ArrayList, my app is not working. Please help me!
MainActivity
{
executeLoadProduct();
arraylistgroup = new ArrayList<String>();
arraylistgroup=TaskLoadProductGroup.getvaluearraylist();
String[] mStringArray = new String[arraylistgroup.size()];
mStringArray = arraylistgroup.toArray(mStringArray);
for (int i = 0; i < mStringArray.length; i++) {
System.out.println("string is2" + (String) mStringArray[i]);
}
executeLoadProduct
private void executeLoadProduct() {
// execute task load product
loadProductGroup = new TaskLoadProductGroup(MainActivity.this);
loadProductGroup.execute();
}
AsyncTask
public class TaskLoadProductGroup extends AsyncTask<String, Void, ArrayList<String>> {
private ActionBarActivity actionBarActivity;
private Context context;
private static ArrayList<String> arrayListgroup;
public TaskLoadProductGroup(ActionBarActivity actionBarActivity) {
this.actionBarActivity = actionBarActivity;
this.context = actionBarActivity.getApplicationContext();
}
#Override
protected void onPreExecute() {
///show progress loading
super.onPreExecute();
}
#Override
protected ArrayList<String> doInBackground(String... url) {
ArrayList<String> listProductgroup = null;
try {
Server server = new Server();
ResListProduct resListProduct = server.getListProducts(context);
//init list item for listview home product
listProductgroup = initItemProduct(resListProduct);
} catch (Exception e) {
}
return listProductgroup;
}
public static ArrayList<String> initItemProduct(ResListProduct rsProduct) {
List<GroupProduct> groups = rsProduct.getGroups();
arrayListgroup = new ArrayList<String>();
for (GroupProduct group : groups) {
// add header group
String s = group.getName();
arrayListgroup.add(s);
}
getvaluearraylist();
// getVarialty();
return arrayListgroup;
}
public static ArrayList<String> getvaluearraylist()
{
return arrayListgroup;
}
#Override
protected void onPostExecute(ArrayList<String> listProductgroup) {
super.onPostExecute(listProductgroup);
}
}
I couldn't identify why are you doing so complex code to print the ArrayList. You can just print that inside onPostExecute method like this,
#Override
protected void onPostExecute(ArrayList<String> listProductgroup) {
super.onPostExecute(listProductgroup);
for (String value : listProductgroup){
Log.d("myTag", value);
}
}
OR
Use loadProductGroup.execute().get() method, but remember this will freeze your UI.
I have four activities in my application A-->B-->C-->D.
I write a My own class MyActivity which extends Activity class. I write this class to handle activity stack.This class has two methods addActivitiyTostack() and getActivityFromStack()
I used a stack for storing activities.
All other activities are extends this class.
When I moved from one activity to other using intent it added to stack.
And when I moved backword activity gets popped up.
I can correctly add activities to stack, But I have problem in popping the activities.
also I have Logout Button on all activities, OnClick of this button I want to close the application how to implement it? Anybody know how to handle activity stack in Android.
This is my code.
package com.example.iprotect;
import java.util.Enumeration;
import java.util.Stack;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
public class MyActivity extends Activity {
private static Stack<Activity> stack = new Stack<Activity>();
static int top=0;
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
addActivityToStack(this);
}
public static void addActivityToStack(MyActivity myActivity) {
// TODO Auto-generated method stub
stack.push(myActivity);
for (int i =0; i< stack.size() ; i++) {
Activity act=stack.get(i);
Log.i("Element in stack", ""+act);
}
}
protected void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
//getActivityFromStack();
//logoutFromApplication();
}
public static void logoutFromApplication() {
// TODO Auto-generated method stub
Enumeration<Activity> enm=stack.elements();
while(enm.hasMoreElements())
{
Activity act=enm.nextElement();
stack.pop();
}
}
public static Activity getActivityFromStack() {
return stack.pop();
}
}
A-->
public class WebServiceActivity extends MyActivity{
EditText editText1, editText2;
Button button;
String response = "";
String email, password;
public final Pattern EMAIL_ADDRESS_PATTERN = Pattern
.compile(".+#.+\\.[a-z]+");
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final EditText editText1 = (EditText) findViewById(R.id.etEmail);
final EditText editText2 = (EditText) findViewById(R.id.etPassword);
button = (Button) findViewById(R.id.loginButton);
button.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
if (TextUtils.isEmpty(editText1.getText().toString())) {
Toast.makeText(getApplicationContext(),
"please enter email id", Toast.LENGTH_SHORT).show();
} else if (TextUtils.isEmpty(editText2.getText().toString())) {
Toast.makeText(getApplicationContext(),
"please enter passwod", Toast.LENGTH_SHORT).show();
} else {
Boolean bool = EMAIL_ADDRESS_PATTERN.matcher(
editText1.getText().toString()).matches();
if (bool == true) {
} else {
Toast.makeText(getApplicationContext(),
"Invalid email id", Toast.LENGTH_SHORT).show();
}
email = editText1.getText().toString();
password = editText2.getText().toString();
// final ProgressDialog pd = ProgressDialog.show(
// WebServiceActivity.this, "Calling webservice...",
// "Please wait...", true, false);
final ProgressBar bar = (ProgressBar) findViewById(R.id.progressBar2);
bar.setVisibility(View.VISIBLE);
new AsyncTask<Void, Void, Void>() {
String r;
protected void onPreExecute() {
};
#Override
protected Void doInBackground(Void... params) {
r = invokeWebService();
return null;
};
protected void onPostExecute(Void result) {
bar.setVisibility(View.VISIBLE);
};
}.execute();
}
}
private String invokeWebService() {
String response = "";
try {
WebService webService = new WebService(
"http://sphinx-solution.com/iProtect/api.php?");
Map<String, String> params = new HashMap<String, String>();
params.put("action", "auth");
params.put("email", email);
params.put("password", password);
response = webService.WebGet("auth", params);
JSONObject jsonObject = new JSONObject(response);
String rr = jsonObject.optString("status");
if (TextUtils.equals(rr, "success")) {
Log.e("MSG", "status==success");
Intent intent = new Intent(WebServiceActivity.this,
SecondActivity.class);
//MyActivity.addActivityToStack(WebServiceActivity.this);
intent.putExtra("email", email);
intent.putExtra("password", password);
WebServiceActivity.this.startActivity(intent);
finish();
} else {
Log.e("MSG", "status ==failed");
}
} catch (Exception e) {
e.printStackTrace();
}
return response;
}
});
}
}
B-->
public class SecondActivity extends MyActivity {
ListView listView;
String email1, password1;
ArrayList<JSONStructure> arrayList = new ArrayList<JSONStructure>();
String r;
String r1;
String tablename;
String rows;
JSONObject jsonObject;
String tablename2;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.second_layout);
Intent intent = getIntent();
email1 = intent.getExtras().getString("email");
password1 = intent.getExtras().getString("password");
Button btn1 = (Button) findViewById(R.id.refreshbutton);
btn1.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
final ProgressDialog pd = ProgressDialog.show(
SecondActivity.this, "Refresh List...",
"Please wait...", true, false);
new AsyncTask<Void, Void, Void>() {
#Override
protected Void doInBackground(Void... params) {
pd.dismiss();
r = invokeWebService();
return null;
}
protected void onPostExecute(Void result) {
};
}.execute();
}
});
Button btn = (Button) findViewById(R.id.logoutbutton);
btn.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
final ProgressDialog pd = ProgressDialog.show(
SecondActivity.this, "Calling webservice...",
"Please wait...", true, false);
new AsyncTask<Void, Void, Void>() {
#Override
protected Void doInBackground(Void... params) {
pd.dismiss();
return null;
}
#Override
protected void onPostExecute(Void result) {
Intent intent = new Intent(SecondActivity.this,
WebServiceActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
SecondActivity.this.startActivity(intent);
}
}.execute();
}
});
listView = (ListView) findViewById(R.id.listview1);
listView.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view,
int position, long id) {
JSONStructure jsonstructure = (JSONStructure) listView
.getAdapter().getItem(position);
final String tablename1 = jsonstructure.getTableName()
.toString();
Intent intent = new Intent(SecondActivity.this,
ProgressBarActivity.class);
//MyActivity.addActivityToStack(SecondActivity.this);
intent.putExtra("tablename", tablename1);
intent.putExtra("Rows", rows);
intent.putExtra("email", email1);
intent.putExtra("password", password1);
SecondActivity.this.startActivity(intent);
}
});
new AsyncTask<Void, Void, Void>() {
#Override
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected Void doInBackground(Void... params) {
r = invokeWebService();
try {
JSONArray jsonArray = new JSONArray();
JSONObject jsonObject = new JSONObject(r);
jsonArray = jsonObject.getJSONArray("Records");
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject c = jsonArray.getJSONObject(i);
tablename = c.optString("TABLE NAME");
rows = c.optString("Rows");
JSONStructure jsonStructure = new JSONStructure();
jsonStructure.setTableName(tablename);
jsonStructure.setRows(rows);
arrayList.add(jsonStructure);
}
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(Void result) {
if (arrayList != null && arrayList.size() > 0) {
MyAdapter adapter = new MyAdapter(SecondActivity.this,
arrayList);
listView.setAdapter(adapter);
}
}
}.execute();
}
private String invokeWebService() {
String response = "";
try {
WebService webService = new WebService(
"http://sphinx-solution.com/iProtect/api.php?");
Map<String, String> params = new HashMap<String, String>();
params.put("action", "getTables");
params.put("email", email1);
params.put("password", password1);
response = webService.WebGet("getTables", params);
} catch (Exception e) {
e.printStackTrace();
}
return response;
}
}
C-->
public class ThirdActivity extends MyActivity {
String tablename1, row1, json1;
ArrayList<JSONStructure> arrayList = new ArrayList<JSONStructure>();
JSONArray jsonArray, jsonArray2;
JSONObject jsonObject;
String row;
String email1, password1;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.third_layout);
ListView listView = (ListView) findViewById(R.id.listview2);
TextView textView = (TextView) findViewById(R.id.title_textview);
Intent intent = getIntent();
tablename1 = intent.getExtras().getString("tablename");
row = intent.getExtras().getString("Rows");
textView.setText(tablename1);
json1 = intent.getExtras().getString("Json");
email1 = intent.getExtras().getString("email");
password1 = intent.getExtras().getString("password");
new AsyncTask<Void, Void, Void>() {
#Override
protected Void doInBackground(Void... params) {
return null;
}
#Override
protected void onPostExecute(Void result) {
Button button = (Button) findViewById(R.id.goback);
button.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(ThirdActivity.this,
SecondActivity.class);
MyActivity.getActivityFromStack();
intent.putExtra("email", email1);
intent.putExtra("password", password1);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
ThirdActivity.this.startActivity(intent);
}
});
}
}.execute();
listView.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view,
final int position, long id) {
final ProgressDialog pd = ProgressDialog.show(
ThirdActivity.this, "Calling webservice...",
"Please wait...", true, false);
new AsyncTask<Void, Void, Void>() {
#Override
protected Void doInBackground(Void... paramArrayOfParams) {
pd.dismiss();
try {
jsonObject = new JSONObject(json1);
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(Void result) {
Intent intent = new Intent(ThirdActivity.this,
FinalActivity.class);
//MyActivity.addActivityToStack(ThirdActivity.this);
intent.putExtra("tablename", tablename1);
intent.putExtra("Json", jsonObject.toString());
intent.putExtra("Row", position);
intent.putExtra("email", email1);
intent.putExtra("password", password1);
ThirdActivity.this.startActivity(intent);
}
}.execute();
}
});
try {
JSONObject jsonObject = new JSONObject(json1);
JSONArray jsonArray = new JSONArray();
jsonArray = jsonObject.getJSONArray("FirstThree");
jsonArray2 = jsonObject.getJSONArray("Color");
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject c = jsonArray.getJSONObject(i);
String one = c.optString("One");
String two = c.optString("Two");
String three = c.optString("Three");
JSONObject c1 = jsonArray2.getJSONObject(i);
String color = c1.optString("color");
JSONStructure jsonStructure = new JSONStructure();
jsonStructure.column1 = one;
jsonStructure.column2 = two;
jsonStructure.column3 = three;
jsonStructure.setColumn1(one);
jsonStructure.setColumn2(two);
jsonStructure.setColumn3(three);
jsonStructure.setColor(color);
arrayList.add(jsonStructure);
Log.e("one", c.optString("One"));
Log.e("two", c.optString("Two"));
Log.e("three", c.optString("Three"));
Log.e("color", c1.optString("color"));
}
} catch (Exception e) {
e.printStackTrace();
}
if (arrayList != null && arrayList.size() > 0) {
MyAdapter1 adapter1 = new MyAdapter1(ThirdActivity.this, arrayList);
listView.setAdapter(adapter1);
}
Button btn = (Button) findViewById(R.id.logoutbutton);
btn.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
final ProgressDialog pd = ProgressDialog.show(
ThirdActivity.this, "Calling webservice...",
"Please wait...", true, false);
new AsyncTask<Void, Void, Void>() {
#Override
protected Void doInBackground(Void... params) {
pd.dismiss();
return null;
}
#Override
protected void onPostExecute(Void result) {
Intent intent = new Intent(ThirdActivity.this,
WebServiceActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
ThirdActivity.this.startActivity(intent);
super.onPostExecute(result);
}
}.execute();
}
});
}
}
Assuming you need this stack solely for the logout function, there are better ways. Use a broadcast instead. Register a BroadcastReceiver in MyActivity.onCreate. The receiver should just call the activity's finish(). Send the broadcast from the button's click listener (btn1? What does that button do? Couldn't guess from the name; better names required ;) ). That's it.