I want to Edit my ListView items. for example; I have a listView item i clicked this item and I add string value with edit text afterwards I again click this item and I add new string value alongside to previous string value, and again, again, again. When I click this item I want edit this listitem. How I do that?
Java sourcecode:
public class MainActivity extends Activity {
TextView tvDers;
EditText etDers, etDersSaati;
EditText etNot;
LinearLayout LayoutDers;
ArrayAdapter<String> adapter;
ListView list;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button btnDersEkle = (Button) findViewById(R.id.btnDersEkle);
list = (ListView) findViewById(R.id.listView1);
adapter = new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_list_item_1);
etDers = new EditText(MainActivity.this);
//Dialog
AlertDialog.Builder build = new AlertDialog.Builder(MainActivity.this);
build.setTitle("Ders Ekle");
build.setView(etDers);
build.setPositiveButton("Tamam", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
adapter.add(etDers.getText().toString());
}
});
list.setAdapter(adapter);
final AlertDialog alertDers = build.create();
btnDersEkle.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
alertDers.show();
}
});
}
}
Save item values in ordering Collection. Set this collection in adapter. Add and remove this values and after call notifyDataSetChanged for adapter.
Try like this.
listView.setOnItemClickListener(new OnItemClickListener(){
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id){
String item = (String) parent.getItemAtPosition(int position);
item += "YourText";
ArrayAdapter adapter = (ArrayAdapter ) parent.getAdapter();
adapter.insert(item, position);
}
Sorry, but now I can't test this code. So I can not say for sure that it is correct. Try different variants and you'll get.
UPDATE
From dialog clickListener you can try this:
#Override
public void onClick(DialogInterface dialog, int which) {
ArrayAdapter adapter = (ArrayAdapter ) listView.getAdapter();
String item = (String) listView.getSelectedItem();
item += "YourText";
adapter.insert(item, position);
}
Related
Been trying to add a favorites system to this notes app where I can tap and hold an item in the list view to add it to another activity with a list view. Here is the activity with the first list.
Items are added via the MainActivity
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button button = (Button) findViewById(R.id.savebutton);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
EditText editTextHeading = (EditText) findViewById(R.id.editTextTextPersonName);
EditText editTextContent = (EditText) findViewById(R.id.contentfield);
String heading = editTextHeading.getText().toString().trim();
String content = editTextContent.getText().toString().trim();
if (!heading.isEmpty()) {
if(!content.isEmpty()) {
try {
FileOutputStream fileOutputStream = openFileOutput(heading + ".txt", Context.MODE_PRIVATE); //heading will be the filename
fileOutputStream.write(content.getBytes());
fileOutputStream.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}else {
editTextContent.setError("Content can't be empty!");
}
}else{
editTextHeading.setError("Heading can't be empty!");
}
editTextContent.setText("");
editTextHeading.setText("");
}
});
Button button2 = (Button) findViewById(R.id.btn_gotosaved);
button2.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
startActivity(new Intent(MainActivity.this, saved.class));
}
});
Button button3 = (Button) findViewById(R.id.btn_faves);
button3.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
startActivity(new Intent(MainActivity.this, favorites.class));
}
});
}
}
Items added will be viewed here
public class saved extends MainActivity {
public static final String EXTRA_MESSAGE = "com.example.notes.MESSAGE";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_saved);
File files = getFilesDir();
String[] array = files.list();
ArrayList<String> arrayList = new ArrayList<>();
final ArrayAdapter adapter = new ArrayAdapter(this, android.R.layout.simple_list_item_1, arrayList);
for (String filename : array) {
filename = filename.replace(".txt", "");
System.out.println(filename);
adapter.add(filename);
}
final ListView listView = (ListView) findViewById(R.id.lv_saved);
listView.setAdapter(adapter);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
String item = listView.getItemAtPosition(position).toString();
Intent intent = new Intent(getApplicationContext(), Note.class);
intent.putExtra(EXTRA_MESSAGE, item);
startActivity(intent);
}
});
listView.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
#Override
public boolean onItemLongClick(AdapterView<?> adapterView, View view, int position, long id) {
String item = listView.getItemAtPosition(position).toString();
}
});
}
}
And tapping and holding an item from there should "favorite" it and copy it to this new activity with another listview
public class favorites extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_favorites);
ListView listView = (ListView) findViewById(R.id.lv_favorites);
}
}
How should I approach this?
With your implementation of creating an individual .txt file in the default directory for each note, this is how you could implement:
listView.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
#Override
public boolean onItemLongClick(AdapterView<?> adapterView, View view, int position, long id) {
String item = listView.getItemAtPosition(position).toString();
Boolean isItemFavorite = item.contains("_favorite");
if (!isItemFavorite){
File itemFile = new File(item + ".txt");
File favoriteItemFile = new File(item + "_favorite.txt");
itemFile.renameTo(favoriteItemFile);
}
}
});
Then in your "favorites" activity you could access all of your note .txt file the same as you do in your "saved" activity - just filtering out any items that don't contain "_favorite" in your "String[] array = files.list();"
Also, some tips: follow naming convention with your activities. "saved" should at least start with an uppercase letter and really should be named something like "SavedNotesListActivity". Also, you should use a room database to keep track of your notes. You should have a favorites table in your room database to keep track of all of your favorites.
I was recently working on a todo list application in android studio where the user will input text through an EditText, and then the String will be added to a listView as shown below.
public class MainActivity extends AppCompatActivity {
private ArrayList<String> items;
private ArrayAdapter<String> itemsAdapter;
private ListView lvItems;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
lvItems = (ListView) findViewById(R.id.lvItems);
items = new ArrayList<>();
itemsAdapter = new ArrayAdapter<>(this,
android.R.layout.simple_list_item_1, items);
lvItems.setAdapter(itemsAdapter);
}
private void setupListViewListener() {
lvItems.setOnItemLongClickListener(
new AdapterView.OnItemLongClickListener() {
#Override
public boolean onItemLongClick(AdapterView<?> adapter,
View item, int pos, long id) {
// Remove the item within array at position
items.remove(pos);
// Refresh the adapter
itemsAdapter.notifyDataSetChanged();
return true;
}
});
}
public void addTask(View v) {
AlertDialog.Builder dialogBuilder = new AlertDialog.Builder(this);
LayoutInflater inflater = this.getLayoutInflater();
final View dialogView = inflater.inflate(R.layout.dialog, null);
dialogBuilder.setView(dialogView);
final EditText edt = (EditText) dialogView.findViewById(R.id.edit1);
dialogBuilder.setTitle("Add a New Task");
dialogBuilder.setMessage("Enter what you want to do");
dialogBuilder.setPositiveButton("Add", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
String itemText = edt.getText().toString();
itemsAdapter.add(itemText);
edt.setText("");
}
});
dialogBuilder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
}
});
AlertDialog b = dialogBuilder.create();
b.show();
}
}
But the problem I have is that when the user closes the activity, the state of the ListView will change back to it's original value.
I want the ListView to retain the Information that has been put inside it when the activity closes.
How do I go about this?
There are many ways to save data in your app.
You can use the following options:
SharedPreferences
Files
SQLite (with plain sql or with the framework Room)
For more information check this link : https://developer.android.com/training/data-storage/index.html
Usually for this situation using Sqlite
But you can use others way such as Shared preference or File
Like you can see here: https://developer.android.com/guide/topics/data/data-storage.html
Unable to instantiate activity Component, ClassCastExceptioI'm new to android and so i followed different tutorials to accomplish my task. I'm having an error and despite all efforts it's still unable to resolve. I've a main activity through which i call a positive active(if user selects "yes" on alert). The positive activity basically contains a listView of three items and i want to display the contacts of mobile when user clicks on the first item.
I put the code of contacts retrieving in the fragment class but it's giving the error of casting even when i didn't use simple intent to call the fragment.
The code for main activity is as follows:
public class activity_home extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
Context context = this;
new AlertDialog.Builder(context)
.setTitle("Alert")
.setMessage("Do you want to enable the app right now?")
.setPositiveButton("Yes", new DialogInterface.OnClickListener()
{
public void onClick(DialogInterface dialog,int id) {
// go to a new activity of the app
Intent positiveActivity = new
Intent(getApplicationContext(),
PositiveActivity.class);
startActivity(positiveActivity);
}
})
.setNegativeButton("No", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// do nothing
}
})
.setNeutralButton("Remind Me later", new
DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int
which) {
// do nothing
}
}
)
.
setIcon(android.R.drawable.ic_dialog_alert)
.show();
}}
PositiveActivity.java:
public class PositiveActivity extends FragmentActivity {
ListView listView;
ArrayList<String> listname;
ArrayList<String> list_no;
Context context;
LayoutInflater inflater;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.positive_view);
Context context = this;
listView = (ListView) findViewById(R.id.mobile_list);
TextView textView = new TextView(context);
textView.setTypeface(null, Typeface.BOLD);
textView.setHeight(100);
textView.setText("Define Specifications for Enabling Auto Pickup!");
listView.addHeaderView(textView);
// Array of strings...
String[] mobileArray = new String[] {"Add Numbers to the list","Select
Timer","Pick Selection Mode"};
final ArrayAdapter <String> adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, android.R.id.text1,
mobileArray);
listView.setAdapter(adapter);
// ListView Item Click Listener
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// ListView Clicked item index
int itemPosition = position;
// ListView Clicked item value
String itemValue = (String)
listView.getItemAtPosition(position);
if (itemPosition == 1) {
ContactListFragment fragmentS1 = new ContactListFragment();
getSupportFragmentManager().beginTransaction().replace
(R.id.headlines_fragment,
fragmentS1).commit();
}}});}}
And the code of Fragment:
import android.support.v4.widget.SimpleCursorAdapter;
public class ContactListFragment extends ListFragment implements
LoaderCallbacks<Cursor> {
private CursorAdapter mAdapter;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// create adapter once
Context context = getActivity();
int layout = android.R.layout.simple_list_item_1;
Cursor c = null; // there is no cursor yet
int flags = 0; // no auto-requery! Loader requeries.
mAdapter = new SimpleCursorAdapter(context, layout, c, FROM, TO, flags);
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
// each time we are started use our listadapter
setListAdapter(mAdapter);
// and tell loader manager to start loading
getLoaderManager().initLoader(0, null, this);
}
// columns requested from the database
private static final String[] PROJECTION = {
Contacts._ID, // _ID is always required
Contacts.DISPLAY_NAME_PRIMARY // that's what we want to display
};
// and name should be displayed in the text1 textview in item layout
private static final String[] FROM = { Contacts.DISPLAY_NAME_PRIMARY };
private static final int[] TO = { android.R.id.text1 };
#Override
public Loader<Cursor> onCreateLoader(int id, Bundle args) {
// load from the "Contacts table"
Uri contentUri = Contacts.CONTENT_URI;
// no sub-selection, no sort order, simply every row
// projection says we want just the _id and the name column
return new CursorLoader(getActivity(),
contentUri,
PROJECTION,
null,
null,
null);
}
#Override
public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
// Once cursor is loaded, give it to adapter
mAdapter.swapCursor(data);
}
#Override
public void onLoaderReset(Loader<Cursor> loader) {
// on reset take any old cursor away
mAdapter.swapCursor(null);
}
}
I'll be grateful if someone points out the mistake in code
try using add instead of replace
getSupportFragmentManager().beginTransaction().add
(R.id.headlines_fragment, fragmentS1).commit();
I currently have this code to display chosen items in a listview:
public class DisplayOrder extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_display_order);
bar();
Button btn = (Button) findViewById(R.id.btnHome);
btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent myIntent = new Intent(DisplayOrder.this, Options.class);
startActivity(myIntent);
}
});
}
private void bar() {
ListView lv = (ListView) findViewById(R.id.listViewDisplay);
List<String> itemsOrdered = new ArrayList<String>();
for (Map.Entry<Item, Integer> entry : Datastore.currentTable.getOrder().getItems().entrySet()) {
itemsOrdered.add((entry.getKey().name) + " x " + String.valueOf(entry.getValue()) + " £" + (entry.getKey().price * entry.getValue()));
}
// This is the array adapter, it takes the context of the activity as a
// first parameter, the type of list view as a second parameter and your
// array as a third parameter.
ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(getBaseContext(), R.layout.activity_display_order, R.id.textView8, itemsOrdered);
lv.setAdapter(arrayAdapter);
}
}
What i want to do is, when I click one of the items, for it to be deleted but Im not sure how to do that. Any guidance would be much appreciated.
You should detect when you click in each item of ListView by setOnItemClickListener.
Then inside this method, just delete the list datasource and notifyDataSetChanged
lv.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView < ? > parent, View view,int position, long id) {
itemsOrdered.remove(position); // remove item at index in list datasource
arrayAdapter.notifyDataSetChanged(); // call it for refresh ListView
Toast.makeText(getApplicationContext(), "remove item at " + position, Toast.LENGTH_LONG).show();
}
});
You have to override the listener “setOnItemClickListener” like this:
listView.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
itemsOrdered.remove(item);
arrayAdapter.notifyDataSetChanged();
}
});
This code removes the ítem from the list, but you have to notify the change to the adapter. When the adapter is notified the listview is updated.
I have a arraylist in which users can input their text. And it is displayed in the screen as a listview. That works, but when i try to get the values of the arraylist it says that: Invalid index 0, size is 0. So im guessing for some reason the listview isnt populating?
This is how I add values to the list:
public class ZaidejaiActivity extends ActionBarActivity implements View.OnClickListener{
public Button mBtnIstrinti;
public Button mBtnPrideti;
public Button mBtnPradeti;
public EditText mYrasytiVarda;
public ListView mZaidejai;
ArrayList<String> list = new ArrayList<String>();
ArrayAdapter<String> adapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_zaidejai);
mBtnPrideti = (Button) findViewById(R.id.pridėtiBtn);
mBtnPrideti.setOnClickListener(this);
mYrasytiVarda = (EditText) findViewById(R.id.VardoYrasymoBtn);
adapter = new ArrayAdapter<String>(this, android.R.layout.simple_expandable_list_item_1, list);
// set the mZaidejai variable to your list in the xml
mZaidejai = (ListView) findViewById(R.id.sarašas);
mZaidejai.setAdapter(adapter);
mZaidejai.setOnItemClickListener(new AdapterView.OnItemClickListener() {
// remove item from List.
#Override
public void onItemClick(AdapterView<?> parent, View view, final int position, long id) {
list.remove(position);
AlertDialog.Builder builder = new AlertDialog.Builder(ZaidejaiActivity.this);
builder.setMessage("Delete?");
builder.setTitle("Confirm Action");
builder.setPositiveButton("Delete", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
adapter.notifyDataSetChanged();
}
//checked.clear();
});
builder.setNegativeButton("Cancel", null);
builder.create();
builder.show();
}
});
mBtnPradeti = (Button) findViewById(R.id.žaistiBtn);
mBtnPradeti.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// count items
int i;
for (i = adapter.getCount() - 1; i >= 0; i--) {
String obj = adapter.getItem(i);
// send items to other activity
Intent pradetiZaidima = new Intent(v.getContext(), ZaidimasActivity.class);
pradetiZaidima.putExtra("playerList", obj);
startActivity(pradetiZaidima);
}
}
});
}
#Override
public void onClick(View v) {
String input = mYrasytiVarda.getText().toString();
if(input.length() > 0)
{
// add string to the adapter, not the listview
adapter.add(input);
// no need to call adapter.notifyDataSetChanged(); as it is done by the adapter.add() method
}else{
AlertDialog alertDialog = new AlertDialog.Builder(this).create();
alertDialog.setTitle("Klaida:");
alertDialog.setMessage("Blogai yrašytas vardas");
alertDialog.setButton("OK", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// here you can add functions
}
});
alertDialog.show();
}
}
EDIT
In this activity I want to get the values of the list:
public class ZaidimasActivity extends ZaidejaiActivity {
public TextView mZaidejas;
public TextView mKlausimas;
public Button mKitasKlausimas;
public Button mGryzti;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_zaidimas);
/** //get the player list from ZaidejaiActivity
Bundle recdData = getIntent().getExtras();
String myVal = recdData.getString("playerList"); */
//show the first players name
mZaidejas = (TextView)findViewById(R.id.ZaidejoVardas);
mZaidejas.setText(list.get(0));
/** mGryzti = (Button)findViewById(R.id.GryztiMeniuBtn);
mKitasKlausimas = (Button)findViewById(R.id.KitasBtn);
mKitasKlausimas.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
}
});
*/
Unfortunately your list==empty. So add some values on it.
list.add("ABC");
list.add("XYZ");
and then setAdapter
adapter = new ArrayAdapter<String>(this, android.R.layout.simple_expandable_list_item_1, list);
mZaidejai = (ListView) findViewById(R.id.sarašas);
mZaidejai.setAdapter(adapter);
Your not adding any values to it. And your list is empty and add some values to it like list.add("hyd");
list.add("city");
and pass those values to adapter
Rather doing
adapter.add(input);
Do
list.add(input);
adapter.notifyDataSetChanged();
So, as others have said you should change the adapter.add(input); on the onClick method to
list.add(input);
adapter.notifyDataSetChanged();
Also, on an unrelated matter, you should really move the list.remove(position); call to the following onClick method of the positive button, before the adapter.notifyDataSetChanged(); call, so it wont be removed if the user cancels the action :)
at the first time your list adapter is empty (getCount() = 0) and you do -1 in the for
mBtnPradeti.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// count items
int i;
if (adapter.getCount() > 0)
{
for (i = adapter.getCount() - 1; i >= 0; i--) {
String obj = adapter.getItem(i);
// send items to other activity
Intent pradetiZaidima = new Intent(v.getContext(), ZaidimasActivity.class);
pradetiZaidima.putExtra("playerList", obj);
startActivity(pradetiZaidima);
}
}
}
});
and for this code :
mZaidejas.setText(list.get(0));
but on Create your list is empty !!!