Develop Reference

Update Listview in first activity after returning from second activity

I have a List View in one activity with one info icon in custom adapter. When user taps on that info button then the next activity will open and after marking attendance in next activity when user taps the update button then the second activity should finish and first activity listview should be updated.
What i successfully did:
I have successfully mark the attendance and change the color of listview but i did that after closing the second activity and restarting the first activity. In this way the listview gets updated because of starting activity again.
What I am unable to do:
I want that when user taps on update button then only finish() will call and user returns to previous first activity with listview updated. But when i do so then the listview not get updated. I have to go back and open the activity again then the listview gets updated otherwise not. I do not want that. I also tried to notify adapter in the onResume method of first activity so that when user returns from second activity then the first activity listview adapter will be updated because of onResume method but it isn't work. Please Help
My Listview Activity Code:
public class TeacherWebserviceMainList extends Activity {
int attentedncemarkedCount = 0;
TextView addteacher;
DatabaseHandler databasehandler;
DetailsTeacherwebservice details;
String emis;
ArrayList<DetailsTeacherwebservice> addas = new ArrayList<DetailsTeacherwebservice>();
CustomAdapterTeacherWebservice cusadapter;
ArrayList<DetailsTeacherwebservice> teacherList;
private ListView listcontent = null;
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.teacherwebservicemainlist );
addteacher = (TextView) findViewById(R.id.addteachermenu);
databasehandler = new DatabaseHandler(TeacherWebserviceMainList.this);
listcontent = (ListView) findViewById(R.id.teacher_list);
teacherList = databasehandler.teacherwebserviceList(emis);
Rsults();
}
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == 1) {
if(resultCode == RESULT_OK) {
String update = data.getStringExtra("update");
if(update.equals("1"))
{
//cusadapter.
CustomAdapterTeacherWebservice adapter = new CustomAdapterTeacherWebservice(this, addas);
listcontent.setAdapter(adapter);
}
}
}
}
private void Rsults() {
addas.clear();
//DatabaseHandler databaseHandler=new DatabaseHandler(this);
//ArrayList<ArrayList<Object>> data = databaseHandler.abcTeacherNew();
for (int p = 0; p < teacherList.size(); p++) {
details = new DetailsTeacherwebservice();
//ArrayList<Object> baris = data.get(p);
details.setId(teacherList.get(p).getId());
details.setTeachername(teacherList.get(p).getTeachername());
details.setTeachercnic(teacherList.get(p).getTeachercnic());
details.setTeacherno(teacherList.get(p).getTeacherno());
details.setTeachergender(teacherList.get(p).getTeachergender());
details.setAttendance(teacherList.get(p).getAttendance());
details.setTeacherattendancedetails(teacherList.get(p).getTeacherattendancedetails());
details.setAttendancedatesince(teacherList.get(p).getAttendancedatesince());
details.setAttendancetrasnferschool(teacherList.get(p).getAttendancetrasnferschool());
addas.add(details);
}
cusadapter = new CustomAdapterTeacherWebservice(TeacherWebserviceMainList.this, addas);
listcontent.setAdapter(cusadapter);
listcontent.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
}
});
}
My List Adapter Code
public class CustomAdapterTeacherWebservice extends BaseAdapter {
private static ArrayList<DetailsTeacherwebservice> searchArrayList;
DatabaseHandler databaseHandler;
private Context context;
private LayoutInflater mInflater;
public CustomAdapterTeacherWebservice(Context context, ArrayList<DetailsTeacherwebservice> results) {
searchArrayList = results;
mInflater = LayoutInflater.from(context);
databaseHandler = new DatabaseHandler(context);
}
#Override
public int getCount() {
return searchArrayList.size();
}
#Override
public Object getItem(int p) {
return searchArrayList.get(p);
}
#Override
public long getItemId(int p) {
return p;
}
public int getViewTypeCount() {
return 500;
}
#Override
public int getItemViewType(int position) {
return position;
}
#Override
public View getView(final int p, View v, ViewGroup parent) {
ViewHolder holder;
context = parent.getContext();
if (v == null) {
v = mInflater
.inflate(R.layout.teacherwebserviceadapter, null);
holder = new ViewHolder();
holder.name = (TextView) v.findViewById(R.id.teacher_name);
holder.cnic = (TextView) v.findViewById(R.id.teacher_cnic);
holder.no = (TextView) v.findViewById(R.id.teacher_phone);
holder.gender = (TextView) v.findViewById(R.id.gender);
holder.status = (TextView) v.findViewById(R.id.status);
holder.info = (ImageView) v.findViewById(R.id.edit);
holder.l1 = (LinearLayout) v.findViewById(R.id.main);
v.setTag(holder);
} else {
holder = (ViewHolder) v.getTag();
}
holder.name.setText(searchArrayList.get(p).getTeachername());
holder.cnic.setText(searchArrayList.get(p).getTeachercnic());
holder.no.setText(searchArrayList.get(p).getTeacherno());
holder.gender.setText(searchArrayList.get(p).getTeachergender());
holder.status.setText(searchArrayList.get(p).getAttendance());
if (searchArrayList.get(p).getAttendance().equals("Absent"))
{
holder.l1.setBackgroundColor(Color.parseColor("#DB674D"));
}
if (searchArrayList.get(p).getAttendance().equals("Present"))
{
holder.l1.setBackgroundColor(Color.parseColor("#7EB674"));
}
if (searchArrayList.get(p).getAttendance().equals("Transfer Out"))
{
holder.l1.setBackgroundColor(Color.parseColor("#FBE87C"));
}
if (searchArrayList.get(p).getAttendance().equals("Resigned"))
{
holder.l1.setBackgroundColor(Color.parseColor("#4FC3F7"));
}
holder.info.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent view_order_intent = new Intent(context, Teacherwebservicemainlistupdate.class);
view_order_intent.putExtra("ID", searchArrayList.get(p).getId());
view_order_intent.putExtra("tname", searchArrayList.get(p).getTeachername());
view_order_intent.putExtra("tgender", searchArrayList.get(p).getTeachergender());
view_order_intent.putExtra("tcnic", searchArrayList.get(p).getTeachercnic());
view_order_intent.putExtra("tno", searchArrayList.get(p).getTeacherno());
view_order_intent.putExtra("tatt", searchArrayList.get(p).getAttendance());
view_order_intent.putExtra("tattdetails", searchArrayList.get(p).getTeacherattendancedetails());
view_order_intent.putExtra("tattdatesince", searchArrayList.get(p).getAttendancedatesince());
view_order_intent.putExtra("tatttrasnferout", searchArrayList.get(p).getAttendancetrasnferschool());
//context.startActivity(view_order_intent);
((Activity)context).startActivityForResult(view_order_intent, 1);
}
});
return v;
}
static class ViewHolder {
TextView name, cnic, no, gender,status;
ImageView info;
LinearLayout l1;
}
here in adapter code when INFO button is clicked then another activity starts in which user can update the attendance.
This is Update activity code when button clicked:
update.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
DetailsTeacherwebservice schoolinfo = new DetailsTeacherwebservice();
schoolinfo.setTeachername(teachername.getText().toString());
schoolinfo.setTeacherno(teacherno.getText().toString());
schoolinfo.setTeachercnic(teachercnic.getText().toString());
schoolinfo.setTeachergender(teachergender.getText().toString());
schoolinfo.setAttendance(teachergroupstr);
schoolinfo.setTeacherattendancedetails(absentgrpstr);
schoolinfo.setAttendancedatesince(txtDate.getText().toString());
schoolinfo.setAttendancetrasnferschool(transferOutSchool.getText().toString());
databasehandler.updateteacherwebservice(schoolinfo, emis, identity);
Toast.makeText(Teacherwebservicemainlistupdate.this, "Updated Successfully", Toast.LENGTH_SHORT).show();
Intent intent = new Intent();
intent.putExtra("update", "1");
setResult(RESULT_OK, intent);
finish();
}
}
});
I can start the listview activity again when update button is clicked but that changes the index of the list item clicked i.e. because activity starts again. How ever what i want is that if i clicked on 10th item then when next activity opens and user updates attendance then it returns back to previous activity on same index position so that the user do not have to scroll again to go back on 10th item

Add this code for list item click:
Intent i = new Intent(context, YourAcitivityName.class);
i.putExtra("position",p);
startActivityForResult(i, 1);
Add this code in update button:
Intent intent = new Intent();
intent.putExtra("update", "1");
intent.putExtra("position",getIntent().getIntExtra("position",0));
setResult(RESULT_OK, intent);
finish();
When you get back from activity to the activity where list view is implemented this method called:
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == 1) {
if(resultCode == RESULT_OK) {
String update = data.getStringExtra("update");
if(update.equals("1"))
{
// add your code to update list view
teacherList = databasehandler.teacherwebserviceList(emis);
Rsults();
YourAdapterClassName adapter = new YourAdapterClassName(this, arrList);
listView.setAdapter(adapter);
listView.smoothScrollToPosition(getIntent().getIntExtra("position",0));
}
}
}
}

The following are two examples, the first is an example where the source for the ListView is a List (and in this case using a Custom Adapter), the second is where the source is a Cursor (using SimpleCursorAdapter)
The trap many fall into is just updating the List using something like :-
myList = method();
myAdapter.notifyDataSetChanged();
At a guess, that's the trap you've fallen into.
When what should be done is to use the List's methods to alter it (e.g. clear, add, addAll, remove).
I believe this explains the reasoning - Is Java “pass-by-reference” or “pass-by-value”?
Example 1 - List as the source :-
/**
* Build or rebuild the List of TaskData's, instantiate the
* Custom Array Adapter if needed and also notify the adapter
* if the List may have been changed.
*/
private void prepTasksCustomArrayList() {
// Determine if the adpater needs to be notified of changes
boolean notify_dataset_changed = (mCsr != null && mCustomArrayAdapter != null);
// If the List is not null then assume that it has changed
// otherwise just get the List
if (mTasks != null) {
mTasks.clear();
mTasks.addAll(dbhlpr.getAllTasks());
} else {
mTasks = dbhlpr.getAllTasks();
}
// If the adapter is null then instantiate it
if (mCustomArrayAdapter == null) {
mCustomArrayAdapter = new CustomArrayAdapter(
this,
R.layout.taskdata_item,
mTasks);
}
// Notify the adapter that the List has changed
if (notify_dataset_changed) {
mCustomArrayAdapter.notifyDataSetChanged();
}
}
Notes
This is used to both setup and alter/update the ListView that the adpater is attached to.
All that is needed is to call the method at the appropriate place/s in the code e.g. in the Activities onCreate, onResume, after onItemClick/LongClick.
e.g in onCreate :-
mTaskList = this.findViewById(R.id.tasklist); // The ListView
prepTasksCustomArrayList()
mTaskList.setAdapter(mCustomArrayAdapter)
and in onresume just (in conjunction with the 3 lines in onCreate)
prepTasksCustomArrayList()
I don't believe that this way is very common, normally you see the adapter being setup in onCreate.
mTasks.addAll(dbhlpr.getAllTasks()); is what gets the source data.
Example 2 - Cursor as the Source
/**
* Build or rebuild the List via Cursor using the bespoke layout
*/
private void prepCursorListBespoke() {
boolean swapcursor = (mCsr != null && mCursorAdapter2 != null);
if (mCursorAdapter2 == null) {
mCursorAdapter2 = new SimpleCursorAdapter(this,R.layout.taskdata_item,mCsr,
new String[]{ Datasource.TASKS_ID_COL,
Datasource.TASKS_TYPE_COL,
Datasource.TASKS_NAME_COL,
Datasource.TASKS_OWNER_COL,
Datasource.TASKS_EXPIRATION_COL},
new int[]{R.id.task_id,
R.id.task_type,
R.id.task_name,
R.id.task_owner,
R.id.task_expiration},
0);
}
if (swapcursor) {
mCursorAdapter2.swapCursor(mCsr);
}
}
Notes
The prepCursorListBespoke method is used in the same way as for example 1.
notifyDataSetChanged could be used instead of swapCursor
I use swapCursor because it's more descriptive).
However, you can only use swapCursor for Cursors.
Added
The following changes may work, roughly speaking I've applied the List example above.
i.e. Rsults is called by onResume(added) which will notify the adapter that the data has been changed.
The code hasn't been tested as there was insufficient code. (a no code for DatabaseHandler class, and b) no code for DetailsTeacherwebservice class). As such there may be errors.
Look for //++++++++++++++... comments should follow to say what has been done/changed.
public class MainActivity extends Activity {
int attentedncemarkedCount = 0;
TextView addteacher;
DatabaseHandler databasehandler;
DetailsTeacherwebservice details;
String emis;
ArrayList<DetailsTeacherwebservice> addas = new ArrayList<DetailsTeacherwebservice>();
CustomAdapterTeacherWebservice cusadapter;
ArrayList<DetailsTeacherwebservice> teacherList;
private ListView listcontent = null;
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.teacherwebservicemainlist);
addteacher = (TextView) findViewById(R.id.addteachermenu);
databasehandler = new DatabaseHandler(TeacherWebserviceMainList.this);
listcontent = (ListView) findViewById(R.id.teacher_list);
//+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
//MOVED On ItemClickListener block FROM Rsults to here.
listcontent.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
}
});
//+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
teacherList = databasehandler.teacherwebserviceList(emis);
Rsults();
}
// Probably don't even need onActivityResult
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == 1) {
if (resultCode == RESULT_OK) {
String update = data.getStringExtra("update");
if (update.equals("1")) {
//cusadapter.
//CustomAdapterTeacherWebservice adapter = new CustomAdapterTeacherWebservice(this, addas);
//+++++++++++++++++++++++++++++++++++
// Commented out
//listcontent.setAdapter(adapter);
}
}
}
}
//+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// Added onResume to call Rsults
#Override
public void onResume() {
super.onResume();
Rsults();
}
private void Rsults() {
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// ADDED 4 lines to see if the notifyDataSetChanged is required
boolean notifydschg_needed = false;
if (cusadapter != null) {
notifydschg_needed = true;
}
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// YOU NEED TO GET THE TEACHER LIST AGAIN AS THE DB HAS CHANGED
teacherList = databasehandler.teacherwebserviceList(emis);
addas.clear();
//DatabaseHandler databaseHandler=new DatabaseHandler(this);
//ArrayList<ArrayList<Object>> data = databaseHandler.abcTeacherNew();
for (int p = 0; p < teacherList.size(); p++) {
details = new DetailsTeacherwebservice();
//ArrayList<Object> baris = data.get(p);
details.setId(teacherList.get(p).getId());
details.setTeachername(teacherList.get(p).getTeachername());
details.setTeachercnic(teacherList.get(p).getTeachercnic());
details.setTeacherno(teacherList.get(p).getTeacherno());
details.setTeachergender(teacherList.get(p).getTeachergender());
details.setAttendance(teacherList.get(p).getAttendance());
details.setTeacherattendancedetails(teacherList.get(p).getTeacherattendancedetails());
details.setAttendancedatesince(teacherList.get(p).getAttendancedatesince());
details.setAttendancetrasnferschool(teacherList.get(p).getAttendancetrasnferschool());
addas.add(details);
}
//+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
//Just create the adapter and attach it to the listview once
if (cusadapter == null) {
cusadapter = new CustomAdapterTeacherWebservice(TeacherWebserviceMainList.this, addas);
listcontent.setAdapter(cusadapter);
}
//+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// Notify the adapter that the data has been changed
if(notifydschg_needed) {
cusadapter.notifyDataSetChanged();
}
}
}

// you have to set data in adapter in onResume method
#Override
protected void onResume() {
super.onResume();
}

You can use eventbus for this case:
This is an example:
In your build.gradle file
compile 'org.greenrobot:eventbus:3.0.0'
In Activity has listview:
#Override
public void onStart() {
super.onStart();
EventBus.getDefault().register(this); // register event
}
#Override
public void onStop() {
super.onStop();
EventBus.getDefault().unregister(this); // unregister event
}
#Subscribe(threadMode = ThreadMode.MAIN)
public void onEvent(EventBusInfo eventBusInfo) {
if (eventBusInfo.getProcessId() == 99) {
// eventBusInfo.getData();
notifyDataSetChanged();
}
}
In Update Activity
yourButtonFinish.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
finish();
EventBusInfo event = new EventBusInfo();
event.setProcessId(99);
//event.setData(object) //if you want get data back
EventBus.getDefault().post(event);
}
});
Class EventBusInfo
public class EventBusInfo {
private int processId;
private Object data;
public EventBusInfo(int processId, Object data) {
this.processId = processId;
this.data = data;
}
public EventBusInfo() {
}
public EventBusInfo(int processId) {
this.processId = processId;
}
public Object getData() {
return data;
}
public void setData(Object data) {
this.data = data;
}
public int getProcessId() {
return processId;
}
public void setProcessId(int processId) {
this.processId = processId;
}
}

save the list items in every change then restart the Activity of adapter with intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP) to close the old ListView.
Is what I do and it works fine.
if the list it is not empty, I restart the activity with the adapter and I have a new ListView closing the previous one. Or if it is empty, I start a different activity (to not have an empty ListView)
Saving and loading the list items every time to SharedPreferences with Gson
For a reason notifyDataSetChanged() does not work good in my case so I prefer this solution.

Check whether the check box is checked

Activity A has a listView , Activity B has a checkBox and save button.
When save button in B is clicked, it will return to Activity A. When the list in Activity A is pressed, how to show the check box is checked in Activity B if it is checked before return to A ?
Activity B
if(getIntent().getExtras()!=null) // when Activity A list is pressed
{
final String from = getIntent().getStringExtra("from");
travelFrom.setText(from);
// how to show check box is checked ?
}
save.setOnClickListener(new View.OnClickListener() { // if save button clicked, return from and outstation to A
#Override
public void onClick(View v) {
String from=travelFrom.getText().toString();
returnIntent.putExtra("from", from);
if(checkbox.isChecked()) {
returnIntent.putExtra("outstation", checkbox.getText().toString());
}
}
});
Activity A
listview.setOnItemClickListener(new AdapterView.OnItemClickListener() { // if listView is clicked
#Override
public void onItemClick(AdapterView<?> a, View v, int position, long id) {
mClickedPosition = position;
Object o = listview.getItemAtPosition(position);
SearchResults fullObject = (SearchResults) o;
String from=fullObject.getFrom();
Intent i = new Intent(getApplication(),B.class);
i.putExtra("from",from);
startActivityForResult(i, PROJECT_REQUEST_CODE);
}
});
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) { // receive from Activity B and populate ListView A
if (resultCode == RESULT_OK) {
if (requestCode == PROJECT_REQUEST_CODE) {
from=data.getStringExtra("from");
check=data.getStringExtra("outstation");
objMyCustomBaseAdapter.addNewItem(from,check); // save from and "outstation" into MySQL
}
}
}
When I press the list in A to B, the check box always not checked. How to make it check ?

Do something like implementing setOnclicklistner for checkbox. and assume an int variable to be zero. and when ever we click the checkbox increase the number by 1 every time. When we are moving from one activity to another send the data of int variable to Activity B. check Activity check the condition int variable as variable%2 if the value is equal to 1 the check box is checked. else it is not.

Assuming you have some object with this...
class MyData {
private boolean check;
public boolean getCheck() { return check; }
}
Here is some rough pseudo-code to demonstrate the concept, so not copy-paste worthy
Activity A - Pass in the boolean value that you want to the next activity
class ActivityA {
private ListView listView
onCreate() {
listView = (ListView) findViewById(R.id.list);
ArrayAdapter adapter = new ArrayAdapter();
listView.setAdapter(adapter);
listView.setOnItemClickListener( new ItemClickListener() {
onClick(int position) {
MyData listObject = adapter.getItem(position);
boolean checked = listObject.getCheck();
Intent i = new Intent(ActivityA.this, ActivityB.class);
i.putExtra("checkTheBox", check);
startActivity(i);
}
});
}
}
Activity B - Get the value out of the intent and set the checkbox to checked
class ActivityB {
private Checkbox checkbox;
onCreate() {
checkbox = (Checkbox) findViewById(R.id.checkbox);
Bundle extras = getIntent().getExtras();
if (extras != null) {
checkbox.setChecked(extras.getBooleanExtra("checkTheBox"));
}
}
}

You have to save the checked status for the selected list item when returning back from Activity B to Activity A.
In order to do that, you can simply store information in Activity A for the currently selected list item.
(for example TreeMap<View, Boolean> - item-> isSelected)
Then in onActivityResult you can set if there has been a check or not for the last selected item. When selecting again, before you create the intent you can check if this item has already been selected.

To know ActivityA ListItem is checked in ActivityB (ie CheckBox) or not. Check this below code hope this helps
ActivityA stuff
int selectedPosition;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//your UI setup and findViewById stuff
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
selectedPosition = position;
startActivityForResult(activityBIntent, REQ_CODE);
}
});
}
int REQ_CODE = 7;
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == REQ_CODE)
if (resultCode == RESULT_OK) {
adapter.changeStatus(selectedPosition, true);//update adapter
} else {
//checkbox not checked
adapter.changeStatus(selectedPosition, false);//update adapter
}
}
ActivityB stuff
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//your UI stuff
setResult(RESULT_CANCELED);//default
//check box setup and save button onclick listener
}
#Override
public void onClick(View v) {
if(v.getId()==R.id.save_button){
if (checkBox.isChecked())
setResult(RESULT_OK);
else
setResult(RESULT_CANCELED);//default
finish();//finish ActivityB and take the result to ActivityA
}
}

Passing values to Activities with putExtra()

I am trying to pass a value on my ListView to my second activity using Intents. I am not sure how to pass the text value to the second activity my Intent leads to. Right now my Intent is able to connect to the second activity on tap but it doesn't pass the string of the tapped value.
I feel that I need to pass something into my launchEditItem() but I am not sure what. These are the two functions I am dealing with right now.
private void launchEditItem() {
Intent i = new Intent(this, EditItemActivity.class);
i.putExtra("itemOnList", ); // list item into edit text
startActivity(i);
}
private void setupEditItemListener() { // on click, run this function to display edit page
lvItems.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> adapter, View item, int pos, long id) {
launchEditItem();
}
});
}
I'm not sure what value to place into the i.putExtra(), but I think I need to pass an argument into the launchEditItem().
This is what is currently in my second Activity:
public class EditItemActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_edit_item);
Intent i = getIntent();
String ItemToEdit = i.getStringExtra("itemOnList");
// place into EditText using ItemToEdit
}
I'm also not sure how to place this String value (ItemToEdit) into an EditText box. I'm new to android dev so I'm learning as much as I can thank you!
* EDIT *
I guess I'm a bit too vague in my question. Here is the entire code of the small app I am working on
public class ToDoActivity extends Activity {
private ArrayList<String> todoItems;
private ArrayAdapter<String> todoAdapter; // declare array adapter which will translate the piece of data to teh view
private ListView lvItems; // attach to list view
private EditText etNewItem;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_to_do);
etNewItem = (EditText) findViewById(R.id.etNewItem);
lvItems = (ListView) findViewById(R.id.lvItems); // now we have access to ListView
//populateArrayItems(); // call function
readItems(); // read items from file
todoAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, todoItems); //create adapter
lvItems.setAdapter(todoAdapter); // populate listview using the adapter
//todoAdapter.add("item 4");
setupListViewListener();
setupEditItemListener();
}
private void launchEditItem() {
Intent i = new Intent(this, EditItemActivity.class);
i.putExtra("itemOnList", ); // list item into edit text
startActivity(i);
}
private void setupEditItemListener() { // on click, run this function to display edit page
lvItems.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> adapter, View item, int pos, long id) {
launchEditItem();
}
});
}
private void setupListViewListener() {
lvItems.setOnItemLongClickListener(new OnItemLongClickListener() {
#Override
public boolean onItemLongClick(AdapterView<?> adapter, View item, int pos, long id) {
todoItems.remove(pos);
todoAdapter.notifyDataSetChanged(); // has adapter look back at the array list and refresh it's data and repopulate the view
writeItems();
return true;
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.to_do, menu);
return true;
}
public void onAddedItem(View v) {
String itemText = etNewItem.getText().toString();
todoAdapter.add(itemText); // add to adapter
etNewItem.setText(""); //clear edit text
writeItems(); //each time to add item, you want to write to file to memorize
}
private void readItems() {
File filesDir = getFilesDir(); //return path where files can be created for android
File todoFile = new File(filesDir, "todo.txt");
try {
todoItems = new ArrayList<String>(FileUtils.readLines(todoFile)); //populate with read
}catch (IOException e) { // if files doesn't exist
todoItems = new ArrayList<String>();
}
}
private void writeItems() {
File filesDir = getFilesDir(); //return path where files can be created for android
File todoFile = new File(filesDir, "todo.txt");
try {
FileUtils.writeLines(todoFile, todoItems); // pass todoItems to todoFile
} catch (IOException e) {
e.printStackTrace();
}
}
}

String[] link_list;
int currenttrack=0;
link_list=new String[]{
"W-TE_Ys4iwM",//1
"oozgmH3ZP14",//2
"o_v9MY_FMcw",//3
"36mCEZzzQ3o",//4
}
First activity
list.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
// TODO Auto-generated method stub
currenttrack=arg2;
Intent videoIntent=new Intent(MainActivity.this,VideoView.class);
videoIntent.putExtra("filename", link_list[currenttrack]);
startActivity(videoIntent);
}
});
In your Second Activity
// getting intent data
// get intent data
Intent i = getIntent();
Bundle extras = i.getExtras();
filename = extras.getString("filename");
Log.e("File Name", filename);
and your done :)

In your current Activity, create a new Intent:
Intent i = new Intent(getApplicationContext(), NewActivity.class);
i.putExtra("new_variable_name","value");
startActivity(i);
Then in the new Activity, retrieve those values:
Bundle extras = getIntent().getExtras();
if (extras != null) {
String value = extras.getString("new_variable_name");
}

I am not sure if i understood where is the value. Well if the value is in EditText do something like:
private void launchEditItem(String text) {
Intent i = new Intent(this, EditItemActivity.class);
i.putExtra("itemOnList", text); // list item into edit text
startActivity(i);
}
private void setupEditItemListener() { // on click, run this function to display edit page
lvItems.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> adapter, View item, int pos, long id) {
EditText editView = (EditText) item.findById(R.id.ItemToEdit);
String text = editView != null ? editView.getText().toString() : "";
launchEditItem(text);
}
});
}

1 - I have some doubt with:
i.putExtra("itemOnList", );
You'd better pass a value:
i.putExtra("itemOnList", "something");
2 - To valorize a control, you must obtain a reference to it first. Something like:
EditText edt =
(EditText) findViewById(R.id.activity_edit_item_my_EditText); // or whatever id you assigned to it (it MUST HAVE AN ID)
Do it AFTER setContentView().
Then you can set it's text like:
edt.setText(ItemToEdit); // Now it should contain "something"
Just as simple as that
[EDIT]
If you aren't sure what to pass so is to pass in the "tapped" value in the ListView into the putExtra, modify your listview click handler code:
list.setOnItemClickListener
(
new OnItemClickListener()
{
#Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3)
{
// TODO Auto-generated method stub
Intent videoIntent = new Intent(MainActivity.this, VideoView.class);
videoIntent.putExtra("filename", (((TextView) v).getText().toString());
startActivity(videoIntent);
}
}
);
It should work immediately.

01: Current Activity
String pass_value ="value";
Intent intent = new Intent(getApplicationContext(),NewActivity.class);
intent.putExtra("var_name",pass_value);
startActivity(intent);
02: New Activity
String value = getIntent().getExtras().getString("var_name");

How to access values defined in AsyncTask from an activity

I have code like this
#Override
public void onCreate(Bundle savedInstanceState) {
addItemsOnSpinnerOrgaLevel();
btn_getReport.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
//How can i access map and list defined in orgaLevelTask(AsyncTask)???
Like
String option = parent.getItemAtPosition(pos).toString();
int orgaCode = orgaLevelMap.get(option);
// Both are defined in AsyncTask ??
}); //end of anonymous class
} //end of onCreate()
public void addItemsOnSpinnerOrgaLevel() {
orgaLevelTask = new OrgaLevelTask(AccountReportActivity.this, spinner_orgaLevel, spinner_branch, txt_extra, txt_extra1);
orgaLevelTask.execute();
} //end of addItemsOnSpinnerOrgaLevel()
In AsyncTask onPostExecute() Method i have
#Override
protected void onPostExecute(ArrayList<OrgaLevel> result) {
super.onPostExecute(result);
if (result != null) {
addItemsOnSpinnerOrgaLevel(result);
}
dialog.dismiss();
} //end of onPostExecute()
public void addItemsOnSpinnerOrgaLevel(ArrayList<OrgaLevel> result) {
orgaLevelElementslist = new ArrayList<String>();
orgaLevelElementslist.add("All");
orgaLevelMap = new HashMap<String, Integer>();
orgaLevelMap.put("All", 0);
for (int i=0; i<result.size(); i++) {
OrgaLevel orgaLevelRecord = (OrgaLevel) result.get(i);
String key = orgaLevelRecord.getOrgaName();
String value = orgaLevelRecord.getOrgaCode();
orgaLevelMap.put(key, Integer.parseInt(value));
orgaLevelElementslist.add(key);
} //end of for()
ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(accountReportActivity, android.R.layout.simple_spinner_item, orgaLevelElementslist);
dataAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spinner_orgaLevel.setAdapter(dataAdapter);
setSpinnerOrgaLevelListener();
} //end of addItemsOnSpinnerOrgaLevel()
private void setSpinnerOrgaLevelListener() {
spinner_orgaLevel.setOnItemSelectedListener(new OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parent, View view, int pos,long id) {
String option = parent.getItemAtPosition(pos).toString();
int orgaCode = orgaLevelMap.get(option);
subOrgaLevelTask = new SubOrgaLevelTask(accountReportActivity, spinner_branch, orgaCode);
subOrgaLevelTask.execute();
} //end of onItemSelected()
}); //end of anonymous class
} //end of setSpinnerOrgaLevelListener()
In the subOrgaLevelTask i also have the same hash map as in this class. You can see that what i am trying to do is, put a key value in spinner. So when my btn_getReport button get click then i get the value of the selected item. Like if All is slected then i get 0 and so on. This key value thing is working. The problem is when btn_getReport get click then how can i get the value of the selected item. Because i am filling items in a background thread(In OrgaLevelTask and SubOrgaLevelTask) and my button is in Activity. So how can i do that when button get click, then i get the values from the map defined in OrgaLevelTask and SubOrgaLevelTask ?
Thanks

well, make them public in orgaLevelTask, and simply access them. orgaLevelTask should be a variable in you activity class. Have you tried it? any errors?
You must make sure orgaLevelTask members will be accessed in thread safe manner

Android, add() function of ArrayAdapter not working

I have an ArrayAdapter (myAdapter) attached to an AutoCompleteTextView (textView) component.
Once the user presses a character I would like to populate AutoCompleteTextView's drop down list with items containing this character.
I retrieve the items using AsyncTask (which uses a web service).
I call myAdapter.add(item) but the drop down list is empty.
I added a call myAdapter.getCount() after each addition and it shows zero every time.
Calling notifyDataSetChanged() didn't help.
I even tried to add simple String objects instead of my custom objects, to no avail.
What am I doing wrong?
Edit: I changed the code as miette suggested below but still to no avail.
Generally, what I do is after text is changed in my auto complete text view, I call a new AsyncTask and pass it the entered text and a Handler (see afterTextChanged()). The task retrieves objects relevant to the text and once done the Handler's handleMessage() is called. In handleMessage() I attempt to populate the adapter's objects. But still the adapter's drop down list ends up empty.
Here is my code:
public class AddStockView extends Activity
implements OnClickListener, OnItemClickListener, TextWatcher {
ArrayAdapter<Stock> adapter;
AutoCompleteTextView textView;
Vector<Stock> stocks;
public AddStockView() {
// TODO Auto-generated constructor stub
stocks = new Vector<Stock>();
}
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.add_stock_view);
findViewById(R.id.abort_button).setOnClickListener(this);
adapter = new ArrayAdapter<Stock>(this,
android.R.layout.simple_dropdown_item_1line, stocks);
//adapter.setNotifyOnChange(true);
textView = (AutoCompleteTextView)
findViewById(R.id.search_edit_text);
textView.setAdapter(adapter);
textView.setOnItemClickListener(this);
textView.addTextChangedListener(this);
}
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
switch (v.getId())
{
case R.id.abort_button:
finish();
break;
case R.id.search_edit_text:
break;
}
}
#Override
public void onItemClick(AdapterView<?> parent, View v,
int position, long id) {
// TODO Auto-generated method stub
Stock stockToAdd = (Stock)parent.getAdapter().getItem(position);
//TODO: Add the above stock to user's stocks and close this screen
finish();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
super.onCreateOptionsMenu(menu);
getMenuInflater().inflate(R.layout.menu, menu);
CategoryMenu.getInstance().populateMenu(menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
CategoryMenu.getInstance().menuItemSelected(item, this);
return false;
}
#Override
public boolean onPrepareOptionsMenu(Menu menu) {
return true;
}
#Override
public void afterTextChanged(Editable text) {
// TODO Auto-generated method stub
if (text.toString().equals(""))
return;
new AppTask().execute(new AppTask.Payload(Consts.taskType.SEARCH_STOCK,
new Object[] {text, handler}, this));
}
#Override
public void beforeTextChanged(CharSequence a0, int a1, int a2, int a3) {
// TODO Auto-generated method stub
}
#Override
public void onTextChanged(CharSequence a0, int a1, int a2, int a3) {
// TODO Auto-generated method stub
}
private void addStockItemsToAdapter(Vector<Object> dataItems)
{
for (int i = 0; i <dataItems.size(); i++)
{
Stock stk = (Stock)dataItems.elementAt(i);
stocks.add(stk);
}
}
public void populateAdapter()
{
addStockItemsToAdapter(ContentReader.getInstance.getDataItems());
adapter.notifyDataSetChanged();
int size = adapter.getCount(); // size == 0 STILL!!!!
textView.showDropDown();
}
final Handler handler = new Handler() {
public void handleMessage(Message msg) {
populateAdapter();
}
};
}
Thanks a lot, Rob

I had the exact same problem. After examining the ArrayAdapter and AutoCompleteTextView source code, I found out that the problem was, in short, that:
the original object list is stored in ArrayAdapter.mObjects.
However, AutoCompleteTextView enables ArrayAdapter's filtering, meaning that new objects are added to ArrayAdapter.mOriginalValues, while mObjects contains the filtered objects.
ArrayAdapter.getCount() always returns the size of mObjects.
My solution was to override ArrayAdapter.getFilter() to return a non-filtering filter. This way mOriginalValues is null and mObjects is used instead in all cases.
Sample code:
public class MyAdapter extends ArrayAdapter<String> {
NoFilter noFilter;
/*
...
*/
/**
* Override ArrayAdapter.getFilter() to return our own filtering.
*/
public Filter getFilter() {
if (noFilter == null) {
noFilter = new NoFilter();
}
return noFilter;
}
/**
* Class which does not perform any filtering.
* Filtering is already done by the web service when asking for the list,
* so there is no need to do any more as well.
* This way, ArrayAdapter.mOriginalValues is not used when calling e.g.
* ArrayAdapter.add(), but instead ArrayAdapter.mObjects is updated directly
* and methods like getCount() return the expected result.
*/
private class NoFilter extends Filter {
protected FilterResults performFiltering(CharSequence prefix) {
return new FilterResults();
}
protected void publishResults(CharSequence constraint,
FilterResults results) {
// Do nothing
}
}
}

Create an array adapter with a vector or array like:
ArrayAdapter(Context context, int textViewResourceId, T[] objects)
By initializing your arrayadapter, you will make it listen to objects array. Do not add item to the adapter or clear the adapter, do your additions in "objects" array and also clear it. After changes on this array call
adapter.notifyDataSetChanged();
More specifically
ArrayAdapter<YourContentType> yourAdapter = new ArrayAdapter<YourContentType> (this,R.id.OneOfYourTextViews,YourDataList);
yourAdapter.notifyDataSetChanged();
aTextView.setText(yourAdapter.isEmpty() ? "List is empty" : "I have too many objects:)");
This should be done after loading YourDataList, I checked your code, are you sure handler calls addStockItemsToAdapter() before you look your adapter is empty or not?
You should also check if stocks vector has any elements in it.

Where do you call addItemsToAdapter()?
Can you show us, how you have tried to add simple Strings to your Adapter?
Edit: out of the comments the helpful code sample:
adapter = new ArrayAdapter<Stock>(this, android.R.layout.simple_dropdown_item_1line, stocks);
adapter.notifyDataSetChanged();
textView.setAdapter(adapter);