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I cannot add items to my RecyclerView from another intent

I have two intents.
Main Activity: Containing the Recycler View, showing some default items to make sure it works. An ArrayList is set to the Recycler View, which is the List containing those default items.
Second Activity: A button which will collect the data on the same page and put the data into an object, the object will be added into the Arraylist which set to the Recycler View of the Main Activity.
I made some Toast Message to confirm the object in the 2nd Activity was added to the ArrayList.
//My item
public item(int id, int money, String date, String category, String
description) {
this.id = id;
Money = money;
Date = date;
Category = category;
Description = description;
}
Then I created a class to control my ArrayList
//Building ArrayList
public Util(){
Log.d(TAG, "Util: Start");
if(IncomeItems==null){
IncomeItems = new ArrayList<>();
initIncomeItems();
}
}
private static void initIncomeItems() {
Log.d(TAG, "initIncomeItems: initI");
int Iid = 0
int Money= 0;
String Date = "";
String Category= "";
String Description = "";
Iid++;
IncomeItems.add(new item(Iid, 10000, "8-Jun-2019", "Salary",
"Salary"));
}
//adding item to ArrayList
public boolean addIncomeItem(item Item){
Log.d(TAG, "addIncomeItem: addI");
return IncomeItems.add(Item);
}
//getting ArrayList
public static ArrayList<item> getIncomeItems() {
Log.d(TAG, "getIncomeItems: getI");
return IncomeItems;
}
I set my ArrayList to the RecyclerView in the Main Activity
//Recycler View in Main Activity
RVAdapter IncomeAdapter = new RVAdapter(this);
Util util = new Util();
MainIncomeRV.setAdapter(IncomeAdapter);
MainIncomeRV.setLayoutManager(new GridLayoutManager(this, 1));
IncomeAdapter.notifyDataSetChanged();
IncomeAdapter.setItems(util.getIncomeItems());
In the 2nd Activity, I have a button to create a new item by getting data from the user.(I skipped some Widgets intitiation code here). At last I add the item to the ArrayList which set to the Recycler View in the Main Activity.
//Button in 2nd Activity
SubmitIncomeBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Date = date_day.getSelectedItem().toString() +"-" +
date_month.getSelectedItem().toString() + "-" +
date_year.getSelectedItem().toString();
id++;
item IncomeItem = new item(id,
Integer.parseInt(Money.getText().toString()), Date,
IncomeCategories.getSelectedItem().toString(),
Description.getText().toString());
util=new Util();
util.addIncomeItem(IncomeItem);
Toast.makeText(IncomePage.this, IncomeItem.toString(),
Toast.LENGTH_SHORT).show();
Toast.makeText(IncomePage.this,
String.valueOf(util.getIncomeItems().size()), Toast.LENGTH_SHORT).show();
Log.d(TAG, "onClick: addI");
}
});
}
No error occurred, but the item(IncomeItem) created in the 2nd Activity cannot be added to the Main Activity.
I expected the item will show in the Recycler view when I return to the Main Activity. Is it the problem that I use the return button to go back to the Main Activity?

Following two points should work for you:
You should use same util object which is used in MainActivity
instead of creating new in submit button under 2nd Activity, So pass util object to
2nd activity.
Also pass adapter object to 2nd Activity, so that you can call NotifyDatasetChanged()
function after adding item.

This is how it should work. First create an arrayList in your 2ndActivity.
ArrayList<Item> str = new ArrayList<Item>();
In SubmitIncomeBtn,
SubmitIncomeBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Date = date_day.getSelectedItem().toString() +"-" + date_month.getSelectedItem().toString() + "-" + date_year.getSelectedItem().toString();
id++;
item IncomeItem = new item(id,Integer.parseInt(Money.getText().toString()), Date, IncomeCategories.getSelectedItem().toString(),Description.getText().toString());
str.add(IncomeItem) // add IncomeItem to arrayList
}
});
In 2ndActivity, you need to have this code to pass arrayList to MainActivity.
#Override
public void onBackPressed() {
Intent intent = new Intent();
intent.putExtra("mylist", str);
setResult(1, intent);
}
Finally in MainActivity, add this code to receive data from 2ndActivity
onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == 1) {
if(resultCode == RESULT_OK) {
ArrayList<Item> myList = (ArrayList<Item>) getIntent().getSerializableExtra("mylist");
}
}
}

Calling new activity from an item inside a recyclerview row

I need to call a new activity, when a button inside one of my recyclerview row elements is called. Each row item in the list contains 4 buttons, one of which needs to open a new activity which will be used to edit the data in that row.
Here is the code for my button so far:
public void onBindViewHolder(CounterLayoutAdapter.ViewHolder holder, final
int position) {
final Counter counter = counterList.get(position);
//counter is a class which holds the data that will be displayed on one
//row
String comment = counter.getComment();
String name = counter.getCounterName();
int number = counter.getCurrentValue();
//LocalDate modifyDate = counter.getLastModifyDate();
Button up = holder.itemView.findViewById(R.id.buttonUp);
Button down = holder.itemView.findViewById(R.id.buttonDown);
Button reset = holder.itemView.findViewById(R.id.buttonReset);
Button edit = holder.itemView.findViewById(R.id.buttonEdit);
Button delete = holder.itemView.findViewById(R.id.buttonDelete);
// code for 4 other buttons goes here
//
edit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
}
});
Since I need the activity that I open to return user inputted data for me, I am using startActivityForResult. However, as far as I can tell, this will only work inside an actual activity class.
So then I tried passing the mainactivity context to my CounterLayoutAdapter class, where all of my button code is. However, the OnBindViewHolder method still cannot access it there. So I tried to pass the context to OnBindViewHolder, but that doesn't work either, as it won't override the abstract class if i do that..
So, how on earth can I call a new activity here?
Alternatively, if there is some other way to get user input into 4 fields and return that input back to the adapter, without calling an activity, that would work as well.
EDIT: viewholder and layout inflation
public static class ViewHolder extends RecyclerView.ViewHolder implements
View.OnClickListener {
private TextView name;
private TextView comment;
private TextView number;
//private TextView date;
public ViewHolder(View itemView) {
super(itemView);
itemView.setOnClickListener(this);
comment = itemView.findViewById(R.id.textComment);
name = itemView.findViewById(R.id.textName);
number = itemView.findViewById(R.id.editTextNum);
//date = itemView.findViewById(R.id.textDate);
}
#Override
public void onClick(View view) {}
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View inflatedView =
LayoutInflater.from(parent.getContext()).inflate(R.layout
.row_layout, parent, false);
return new ViewHolder(inflatedView);
}

You can call startActivityForResult() in adapter class.
Get context in adapter like Context context=holder.up.getContext();
then in your button's OnClickListener do this.
edit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent=new Intent(context,ActivityYouWantToStart.class);
//Pass any extras if you want to.
((Activity)context).startActivityForResult(intent,REQUEST_CODE);
}
});
Then in your activity (which contain this recyclerView) override onActivityResult like this
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_CODE) {//same REQUEST_CODE you used in adapter
if (resultCode == RESULT_OK) {
//Do your thing and get the data you want.
adapter.onDataReady(Data data);//where adapter is your recycler adapter,
//and data is whatever data you want to pass to adapter
//(Data you got from the activityResult, do not confuse it with onActivityResult's parameter 'Intent data')
}
}
}
Finally in your Recycler Adapter class, define onDataReady() function like
public void onDataReady(Data data){
//Update RecyclerView with new data
}
Hope this helps. I once did this, and it works for me. Let me know if you have any problem.

As you see , you do not have to findViewById in onBindViewHolder.
public void onBindViewHolder(CounterLayoutAdapter.ViewHolder holder, final
int position) {
final Counter counter = counterList.get(position);
//counter is a class which holds the data that will be displayed on one
//row
String comment = counter.getComment();
String name = counter.getCounterName();
int number = counter.getCurrentValue();
//LocalDate modifyDate = counter.getLastModifyDate();
holder.edit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
}
});
Then you should init edit in ViewHolder constructor.
public ViewHolder(View itemView) {
super(itemView);
itemView.setOnClickListener(this);
comment = itemView.findViewById(R.id.textComment);
name = itemView.findViewById(R.id.textName);
number = itemView.findViewById(R.id.editTextNum);
//date = itemView.findViewById(R.id.textDate);
// init four button
edit = itemView.findViewById(R.id.buttonEdit)
}

Change SQL query based on button action

I have a listview that displays all the items in my database. I am trying to create a button that will change the data displayed to only show items that match today's date.
What is the best way to change the query that is being run in the app based on a button push and update the listview?
I've played with setting a flag in the onclick() method paired with if-else statements that held the query call, but it did not seem to switch which was being called.
The flag is the boolean filterToday. set in the onClickListener of todayButton.
public class MainActivity extends AppCompatActivity {
public final static String KEY_EXTRA_CONTACT_ID = "KEY_EXTRA_CONTACT_ID";
private ListView listView;
DBHelper dbHelper;
boolean filterToday;
Cursor cursor;
String [] columns;
int [] widgets;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button addButton = (Button) findViewById(R.id.addNew);
addButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(MainActivity.this, AddTaskActivity.class);
intent.putExtra(KEY_EXTRA_CONTACT_ID, 0);
startActivity(intent);
}
});
Button todayButton = (Button) findViewById(R.id.today);
todayButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
filterToday = true;
}
});
dbHelper = new DBHelper(this);
if(filterToday == true){
Calendar cal = Calendar.getInstance();
DateFormat df = new SimpleDateFormat("yyyy-MM-dd");
String date = df.format(cal.getTime());
Toast.makeText(this,date,Toast.LENGTH_LONG).show();
cursor = dbHelper.getTodaysTasks(date);
}
else{
cursor = dbHelper.getAllTasks();
}
columns = new String[] {
DBHelper.TASK_COLUMN_NAME,
DBHelper.TASK_COLUMN_TYPE,
DBHelper.TASK_COLUMN_DATE
};
widgets = new int[] {
R.id.taskName,
R.id.taskType,
R.id.taskDate
};
SimpleCursorAdapter cursorAdapter = new SimpleCursorAdapter(this, R.layout.task_info,
cursor, columns, widgets, 0);
listView = (ListView)findViewById(R.id.listView1);
listView.setAdapter(cursorAdapter);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> listView, View view,
int position, long id) {
Cursor itemCursor = (Cursor) MainActivity.this.listView.getItemAtPosition(position);
int taskID = itemCursor.getInt(itemCursor.getColumnIndex(DBHelper.TASK_COLUMN_ID));
Intent intent = new Intent(getApplicationContext(), AddTaskActivity.class);
intent.putExtra(KEY_EXTRA_CONTACT_ID, taskID);
startActivity(intent);
}
});
}
}
These are the two queries I am trying to switch between:
public Cursor getAllTasks() {
SQLiteDatabase db = this.getReadableDatabase();
Cursor res = db.rawQuery( "SELECT * FROM " + TASK_TABLE_NAME, null );
return res;
}
public Cursor getTodaysTasks(String date){
SQLiteDatabase db = this.getReadableDatabase();
Cursor res = db.rawQuery("SELECT * FROM " + TASK_TABLE_NAME + " WHERE " +
TASK_COLUMN_DATE + " =?", new String[]{date});
return res;
}

OK so the first thing to notice is that your update filterToday = true; inside the onclick listener, the if(filterToday == true){...} outside doesn't know that. That part is only executed once in the oncreate()
If you'd like to perform that action I suggest a small change.. like below
Create a seperate function outside for the data loading
private void LoadMyData() {
if(filterToday == true){
Calendar cal = Calendar.getInstance();
DateFormat df = new SimpleDateFormat("yyyy-MM-dd");
String date = df.format(cal.getTime());
//you might need to update this line
//Toast.makeText(this,date,Toast.LENGTH_LONG).show();
//assume dbHelper is ready at this point
cursor = dbHelper.getTodaysTasks(date);
}
else{
cursor = dbHelper.getAllTasks();
}
}
Call this function inside onclick listner
filterToday = false;//initialize to false if necessary
todayButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
filterToday = !filterToday ;//by doing it like this you can switch back and forth. add/check extra logic if necessary
LoadMyData();
}
});
LoadMyData(); //Call this outside in the oncreate to load the data initially
I'm not suggesting a code improvement here. Just changes to what you already have. Hope it helps.

There were two issues that I ran into, the first was comparing a string to to the SQL string[], which meant while the comparison was working, it did not behave as I expected. Once fixing this issue was updating the ListView object. This was handled by creating a new adapter and attaching it to ListView, which then updates itself.
Per this answer: Refresh Current Fragment (ListView Data) remaining in the same activity
The other option was to call notifyDataSetChanged() on the adapter, but this did not work well with the way I had my program set up.

Android DatePickerDialog parameters

I'm creating button dynamically at runtime which their click event opens a datepickerdialog. So like this:
Button btnDate = new Button(this);
btnDate.setText("Date");
btnDate.setTag(new UDAControlItemTag(q.getiQuestionID(),-1,f.getiSectionID(),f.getiGroup(),-1,"Date",""));
btnDate.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Button tempBtn = (Button)v;
UDAControlItemTag tempQ = (UDAControlItemTag)tempBtn.getTag();
showDialog(DATE_DIALOG_ID_Question);
//tempBtn.setText(Integer.toString(mTempMonth));
}
});
Then I have the listener where i can get the values and stuff but because I'm creating the controls dynamically, i keep these values of each control in an ArrayList with different properties. The issue I have is how to get the parameters i need to correctly determine which button was clicked in order to put in the correct properties for that question into the ArrayList.
private DatePickerDialog.OnDateSetListener mDateSetListenerQuestion =
new DatePickerDialog.OnDateSetListener() {
public void onDateSet(DatePicker view, int year,
int monthOfYear, int dayOfMonth) {
mTempYear = year;
mTempMonth = monthOfYear;
mTempDay = dayOfMonth;
}
};
So in there i have the value of the dialog, but i need to have a QuestionID which is associated to the button that the user clicked, in order to put the value into the ArrayList of all the answers for all that dynamic controls on the activity. I'd really appreciate any ideas, thanks.

Instead of that listener you could use your own class that implements the DatePickerDialog.OnDateSetListener interface and also has a constructor that takes an int, the QuestionID. Something like this:
public class TheSpecialListener implements
DatePickerDialog.OnDateSetListener {
private int id;
public TheSpecialListener(int id) {
this.id = id;
}
public void onDateSet(DatePicker view, int year, int monthOfYear,
int dayOfMonth) {
mTempYear = year;
mTempMonth = monthOfYear;
mTempDay = dayOfMonth;
// id is the QuestionID so you now can identify the Button that started the dialog
}
};
Now when you click a Button you'll update a field with that Button's QuestionID that will be used in the onCreateDialog method(which I don't know how you implemented):
private int questionId;
and in the Button listener:
//...
Button tempBtn = (Button)v;
UDAControlItemTag tempQ = (UDAControlItemTag)tempBtn.getTag();
questionId = //here pass the Button's id or whatever
showDialog(DATE_DIALOG_ID_Question);
and in the onCreateDialog method instantiate the above special listener and pass it the questionId field which will hold the identifier, as it will be updated each time a Button is clicked:
DatePickerDialog spd = new DatePickerDialog(this,
new TheSpecialListener(questionId), 2012, 6, 16);

setText not displaying the value to a TextView

Let me preface that I'm new to programming for Android. I've been doing my due diligence to research to no avail. I have the source code below and I'm having issues with returning the value for returning.
I have the code laid out on eclipse and it's not triggering any errors. But when I build the code below, it comes back with an error. After inspecting the values in debug view, I can see the proper values just not binded to the TextView.
public class MyFirstActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
calculateResult(2012, 9, 29);
}
private void calculateResult(int year, int month, int day) {
long days = 0L;
int returning = 0;
java.util.Calendar cal = new java.util.GregorianCalendar(year, month-1, day);
long todayMI = new java.util.Date().getTime();
long calMI = cal.getTimeInMillis();
long millDiff = calMI - todayMI;
if (millDiff < 0) {
returning = 0;
} else {
days = millDiff / 1000 / 60 / 60;
returning = (int) Math.ceil(days / 24f);
}
TextView days_int_remaining = (TextView) findViewById(R.id.days_int_remaining);
days_int_remaining.setText(returning);
}
}
If it helps, here's the TextView on my layout XML:
<TextView
android:id="#+id/days_int_remaining"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:layout_gravity="center_horizontal|center_vertical"
android:shadowColor="#5000"
android:shadowDx="4"
android:shadowDy="3"
android:shadowRadius="1"
android:textColor="#fff"
android:textSize="70dip"
android:textStyle="bold"
/>
It may be something simple that I'm missing. Anything to help me further understand the code is appreciated!

I believe that the error you get is "runtime-error - close application".
If you look at method setText(...) that is overloaded you will see that it takes arguments with CharSequence (this is probably what you want) and int resId (this is what you provide).
resId - will seek if there is an resource in /values/strings.xml with given name attribute.
The resolution is to provide String:
days_int_remaining.setText(String.valueOf(returning));

just use
TextView days_int_remaining = (TextView) findViewById(R.id.days_int_remaining);
days_int_remaining.setText(String.valueOf(returning));
instead of
TextView days_int_remaining = (TextView) findViewById(R.id.days_int_remaining);
days_int_remaining.setText(returning);

Turn your returning int into a string.

Try this code :
Basically you have to convert your int value to a string before calling setText();
public class MyFirstActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
TextView days_int_remaining = (TextView) findViewById(R.id.days_int_remaining);
int resultat = calculateResult(2012, 9, 29);
days_int_remaining.setText(Integer.toString(resultat));
}
private int calculateResult(int year, int month, int day) {
long days = 0L;
int returning = 0;
java.util.Calendar cal = new java.util.GregorianCalendar(year, month-1, day);
long todayMI = new java.util.Date().getTime();
long calMI = cal.getTimeInMillis();
long millDiff = calMI - todayMI;
if (millDiff < 0) {
returning = 0;
} else {
days = millDiff / 1000 / 60 / 60;
returning = (int) Math.ceil(days / 24f);
}
return returning;
}
}