Develop Reference

Why Todo app not showing the added tasks?

Todo app doesn't show the added task...its like not refreshing the added task. When i close and open the app again, then it shows. I am a beginner so i can,t guess out the problem.
Here is MainActivity.java
package com.ashtiv.dooo;
import androidx.appcompat.app.AlertDialog;
import androidx.appcompat.app.AppCompatActivity;
import android.content.ContentValues;
import android.content.DialogInterface;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
import com.ashtiv.dooo.db.TaskContract;
import com.ashtiv.dooo.db.TaskDbHelper;
import java.util.ArrayList;
public class MainActivity extends AppCompatActivity {
private static final String TAG = "MainActivity";
private TaskDbHelper mHelper;
private ListView mTaskListView;
private ArrayAdapter<String> mAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mHelper = new TaskDbHelper(this);
mTaskListView = (ListView) findViewById(R.id.list_todo);
updateUI();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main_menu, menu);
return super.onCreateOptionsMenu(menu);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.action_add_task:
final EditText taskEditText = new EditText(this);
AlertDialog dialog = new AlertDialog.Builder(this)
.setTitle("Add a new task")
.setMessage("What do you want to do next?")
.setView(taskEditText)
.setPositiveButton("Add", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
String task = String.valueOf(taskEditText.getText());
SQLiteDatabase db = mHelper.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(TaskContract.TaskEntry.COL_TASK_TITLE, task);
db.insertWithOnConflict(TaskContract.TaskEntry.TABLE,
null,
values,
SQLiteDatabase.CONFLICT_REPLACE);
db.close();
}
})
.setNegativeButton("Cancel", null)
.create();
dialog.show();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
public void deleteTask(View view) {
View parent = (View) view.getParent();
TextView taskTextView = (TextView) parent.findViewById(R.id.task_title);
String task = String.valueOf(taskTextView.getText());
SQLiteDatabase db = mHelper.getWritableDatabase();
db.delete(TaskContract.TaskEntry.TABLE,
TaskContract.TaskEntry.COL_TASK_TITLE + " = ?",
new String[]{task});
db.close();
updateUI();
}
private void updateUI() {
ArrayList<String> taskList = new ArrayList<>();
SQLiteDatabase db = mHelper.getReadableDatabase();
Cursor cursor = db.query(TaskContract.TaskEntry.TABLE,
new String[]{TaskContract.TaskEntry._ID, TaskContract.TaskEntry.COL_TASK_TITLE},
null, null, null, null, null);
while (cursor.moveToNext()) {
int idx = cursor.getColumnIndex(TaskContract.TaskEntry.COL_TASK_TITLE);
taskList.add(cursor.getString(idx));
}
if (mAdapter == null) {
mAdapter = new ArrayAdapter<>(this,
R.layout.item_todo,
R.id.task_title,
taskList);
mTaskListView.setAdapter(mAdapter);
} else {
mAdapter.clear();
mAdapter.addAll(taskList);
mAdapter.notifyDataSetChanged();
}
cursor.close();
db.close();
}
}
Here is TaskContract.java
package com.ashtiv.dooo.db;
import android.provider.BaseColumns;
public class TaskContract {
public static final String DB_NAME = "com.ashtiv.dooo.db";
public static final int DB_VERSION = 1;
public class TaskEntry implements BaseColumns {
public static final String TABLE = "tasks";
public static final String COL_TASK_TITLE = "title";
}
}
Here is TaskDbHelper.java
package com.ashtiv.dooo.db;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class TaskDbHelper extends SQLiteOpenHelper {
public TaskDbHelper(Context context) {
super(context, TaskContract.DB_NAME, null, TaskContract.DB_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db) {
String createTable = "CREATE TABLE " + TaskContract.TaskEntry.TABLE + " ( " +
TaskContract.TaskEntry._ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
TaskContract.TaskEntry.COL_TASK_TITLE + " TEXT NOT NULL);";
db.execSQL(createTable);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + TaskContract.TaskEntry.TABLE);
onCreate(db);
}
}
hERE is actvity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:tools="http://schemas.android.com/tools"
tools:context="com.ashtiv.dooo.MainActivity">
<ListView
android:id="#+id/list_todo"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</RelativeLayout>
Here is item_todo.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="center_vertical">
<TextView
android:id="#+id/task_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:text="Hello"
android:textSize="20sp" />
<Button
android:id="#+id/task_delete"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:layout_alignParentRight="true"
android:text="Done"
android:onClick="deleteTask"/>
</RelativeLayout>

The issue was you are not updating the UI after adding a new Todo.
To tackle the issue modify your code as follows.
Edit your onOptionsItemSelected to
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.action_add_task:
addTodo();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
and add this function.
private void addTodo() {
final EditText taskEditText = new EditText(this);
AlertDialog dialog = new AlertDialog.Builder(this)
.setTitle("Add a new task")
.setMessage("What do you want to do next?")
.setView(taskEditText)
.setPositiveButton("Add", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
String task = String.valueOf(taskEditText.getText());
SQLiteDatabase db = mHelper.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(TaskContract.TaskEntry.COL_TASK_TITLE, task);
db.insertWithOnConflict(TaskContract.TaskEntry.TABLE,
null,
values,
SQLiteDatabase.CONFLICT_REPLACE);
db.close();
}
})
.setNegativeButton("Cancel", null)
.create();
dialog.show();
updateUI();
}

The issue you are seeing is because function updateUI() only gets called when your activity is created. You would have to devise a method where updateUI() gets called for each time you make an update to the table.
You could try calling updateUI() whenever you add or remove some tasks. For example:
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.action_add_task:
final EditText taskEditText = new EditText(this);
AlertDialog dialog = new AlertDialog.Builder(this)
.setTitle("Add a new task")
.setMessage("What do you want to do next?")
.setView(taskEditText)
.setPositiveButton("Add", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
String task = String.valueOf(taskEditText.getText());
SQLiteDatabase db = mHelper.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(TaskContract.TaskEntry.COL_TASK_TITLE, task);
db.insertWithOnConflict(TaskContract.TaskEntry.TABLE,
null,
values,
SQLiteDatabase.CONFLICT_REPLACE);
db.close();
//NEW LINE
updateUI();
}
})
.setNegativeButton("Cancel", null)
.create();
dialog.show();
return true;
default:
return super.onOptionsItemSelected(item);
}
}

FirebaseUI populate ListView text not displayed

I am populating a ListView of songs using Firebase database and Firebase-UI, all the dependencies are initialized correctly and the app is connected with the database but when it displays the list it doesn't display the text, just empty boxes like that:
When an item is added to the database then a box is added but it doesn't show the text. Here is the code:
Song class:
package com.example.gloriadesideri.animas;
public class Song
{
private String myName;
private String myURL;
private String myAuthor;
public Song(){
/*myName="";
myURL="";
myAuthor="";*/
}
public Song(String Author, String Song, String URL) {
this.myName=Song;
this.myURL=URL;
this.myAuthor=Author;
}
public String getName()
{
return myName;
}
public String getURL()
{
return myURL;
}
public String getAuthor()
{
return myAuthor;
}
public void setName(String name)
{
this.myName=name;
}
public void setURL ( String URL)
{
this.myURL=URL;
}
public void setAuthor(String author)
{
this.myAuthor=author;
}
}
Song Layout:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_margin="20dp"
android:padding="10dp">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/songName"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/author"/>
</LinearLayout>
Activity that should have the list view:
package com.example.gloriadesideri.animas;
import android.content.Intent;
import android.support.design.widget.NavigationView;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBar;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.MenuItem;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
import com.firebase.ui.database.FirebaseListAdapter;
import com.firebase.ui.database.FirebaseListOptions;
import com.google.firebase.database.ChildEventListener;
import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.Query;
import com.google.firebase.database.ValueEventListener;
import java.util.ArrayList;
import java.util.List;
public class Canzoni extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener
{
//nav view parameters
private DrawerLayout cDrawerLayout;
private ActionBarDrawerToggle cToggle;
//list view parameters
private ListView mListView;
//firebase parameters
private FirebaseListAdapter mAdapter;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_canzoni);
//nav view code
cDrawerLayout= (DrawerLayout) findViewById(R.id.draw_viewC);
cToggle= new ActionBarDrawerToggle(this, cDrawerLayout,R.string.Open, R.string.Close);
cDrawerLayout.addDrawerListener(cToggle);
cToggle.syncState();
ActionBar actionBar = getSupportActionBar();
if (actionBar != null)
actionBar.setDisplayHomeAsUpEnabled(true);
NavigationView cNavigationView = (NavigationView) findViewById(R.id.nav_viewC);
if (cNavigationView != null)
{
cNavigationView.setNavigationItemSelectedListener(this);
}
Query mQuery= FirebaseDatabase.getInstance().getReference().child("songs");
mListView= (ListView) findViewById(R.id.canzoni_list);
FirebaseListOptions<Song> mOptions= new FirebaseListOptions.Builder<Song>()
.setLayout(R.layout.song_layout)
.setQuery(mQuery, Song.class)
.setLifecycleOwner(this)
.build();
mAdapter= new FirebaseListAdapter <Song>(mOptions){
#Override
protected void populateView(View v, Song model, int position) {
TextView songName= v.findViewById(R.id.songName);
TextView songAuthor=v.findViewById(R.id.author);
songName.setText(model.getName());
songAuthor.setText(model.getAuthor());
}
};
mListView.setAdapter(mAdapter);
}
#Override
protected void onStart() {
super.onStart();
mAdapter.startListening();
}
#Override
protected void onStop() {
super.onStop();
mAdapter.stopListening();
}
#Override
public boolean onOptionsItemSelected(MenuItem Item)
{
if(cToggle.onOptionsItemSelected(Item))
{
return true;
}
return super.onOptionsItemSelected(Item);
}
#Override
public boolean onNavigationItemSelected(MenuItem Item)
{
int id = Item.getItemId();
Intent intent;
if (id == R.id.preghiere)
{
intent= new Intent(this, Preghiere.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
this.startActivity(intent);
}
else if ( id== R.id.bans)
{
intent= new Intent(this, Bans.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
this.startActivity(intent);
}
else if (id== R.id.canzoni)
{
intent= new Intent(this, this.getClass());
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
this.startActivity(intent);
}
else if (id==R.id.calendario)
{
intent= new Intent(this, Calendario.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
this.startActivity(intent);
}
else if (id== R.id.per_riflettere)
{
intent= new Intent(this, perRiflettere.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
this.startActivity(intent);
}
else if( id== R.id.home)
{
intent= new Intent(this, MainActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
this.startActivity(intent);
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.draw_viewC);
drawer.closeDrawer(GravityCompat.START);
return true;
}
}
layout of the above activity
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".Canzoni"
android:id="#+id/draw_viewC">
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/canzoni_list">
</ListView>
<android.support.design.widget.NavigationView
android:layout_width="239dp"
android:layout_height="match_parent"
android:layout_gravity="start"
android:background="#color/white"
android:fitsSystemWindows="true"
app:headerLayout="#layout/header"
app:itemIconTint="#color/black"
app:itemTextColor="#color/black"
app:menu="#menu/drawem_menu"
tools:layout_editor_absoluteX="0dp"
tools:layout_editor_absoluteY="0dp"
tools:ignore="MissingConstraints"
android:id="#+id/nav_viewC"/>
</android.support.v4.widget.DrawerLayout>
Any suggestion on how to fix this?
Edit:
the database looks like this:
both writing and reading rules are true
Edit
I have changed the private names in the Song class so they are the same as the database.
private String Author;
private String Song;
private String Url;
it starts working the problem is that now it displays just the author
Update 2

I this code fetch the user data from firebase and show data into recycled view.
In layout i used constaraint layout you can change it..
display_data.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.RecyclerView
android:id="#+id/rvData"
android:layout_width="match_parent"
android:layout_height="match_parent">
</android.support.v7.widget.RecyclerView>
<TextView
android:id="#+id/dlTvEmpty"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="No Found"
android:textSize="16dp"
android:visibility="gone"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>
then after row_layout bind into recycler view..
row_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="10dp">
<TextView
android:id="#+id/rlTvName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Name"
android:textSize="20dp" />
<TextView
android:id="#+id/rlTvEmail"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Email"
android:textSize="20dp"
app:layout_constraintTop_toBottomOf="#+id/rlTvName" />
<TextView
android:id="#+id/rlTvPwd"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Password"
android:textSize="20dp"
app:layout_constraintTop_toBottomOf="#+id/rlTvEmail" />
</android.support.constraint.ConstraintLayout>
then after make pojo class for user that insert into firebase..
User.java
public class User {
public String name;
public String email;
public String pwd;
// Default constructor required for calls to
// DataSnapshot.getValue(User.class)
public User() {
}
public User(String name, String email,String pwd) {
this.name = name;
this.email = email;
this.pwd=pwd;
}
}
then after make adapter class.
DisplayAllData.java
public class DisplayAllData extends RecyclerView.Adapter<DisplayAllData.ItemViewHolder> {
private List<User> mUserLsit = new ArrayList<>();
private Context mContext;
#Override
public ItemViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.row_layout, parent, false);
return new ItemViewHolder(view);
}
public DisplayAllData(Context mContext, List<User> mUserLsit) {
this.mContext = mContext;
this.mUserLsit = mUserLsit;
}
#Override
public void onBindViewHolder(ItemViewHolder holder, int position) {
User user = mUserLsit.get(position);
holder.mTvName.setText(user.name);
holder.mTvEmail.setText(user.email);
holder.mTvPwd.setText(user.pwd);
}
#Override
public int getItemCount() {
return mUserLsit.size();
}
public class ItemViewHolder extends RecyclerView.ViewHolder {
TextView mTvName, mTvEmail, mTvPwd;
public ItemViewHolder(View itemView) {
super(itemView);
mTvEmail = itemView.findViewById(R.id.rlTvEmail);
mTvName = itemView.findViewById(R.id.rlTvName);
mTvPwd = itemView.findViewById(R.id.rlTvPwd);
}
}
}
then after finally make display class to fetch user record from firebase and bind into recyclerview.
DisplayActivity.java
public class DisplayActivity extends AppCompatActivity {
private RecyclerView mRvData;
private DisplayAllData allDataAdapter;
private DatabaseReference mDatabase;
private TextView mTvEmpty;
private FirebaseDatabase mFirebaseInstance;
private List<User> mUserList = new ArrayList<>();
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.display_data);
initView();
}
private void initView() {
mFirebaseInstance = FirebaseDatabase.getInstance();
mDatabase = mFirebaseInstance.getReference("usersDb/UserTable");
mRvData = findViewById(R.id.rvData);
mTvEmpty = findViewById(R.id.dlTvEmpty);
mRvData.setLayoutManager(new LinearLayoutManager(this));
mDatabase.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
mUserList.clear();
for (DataSnapshot dataSnapshot1 : dataSnapshot.getChildren()) {
User user = dataSnapshot1.getValue(User.class);
mUserList.add(user);
}
allDataAdapter = new DisplayAllData(DisplayActivity.this, mUserList);
mRvData.setAdapter(allDataAdapter);
allDataAdapter.notifyDataSetChanged();
if (mUserList.isEmpty())
mTvEmpty.setVisibility(View.VISIBLE);
else
mTvEmpty.setVisibility(View.GONE);
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
}

After few experiments with code like change this
songName.setText(model.getName());
songAuthor.setText(model.getAuthor());
to this
songName.setText(model.getURL());
songAuthor.setText(model.getAuthor());
I have learned that the problem was really the names I gave to the privates and the names I gave to the get-methods in the Song class. The names of the privates should be the same as the database fields and the names of the methods should be getYourPrivateName().

In your database, you have a property under the name of the song called myAuthor but in the model class, you have the field named Author, both should be the same.
To solve this, you have two solutions. First one would be to delete all the record from your database and add fresh data according to your model class. Make sure that the properties in your database are added using the name od your field that exist in your model class: myName, myURL, myAuthor and NOT Author, Song, Url.
If you are not in testing mode, then just use annotation in your model class like this:
#PropertyName("Song")
private String myName;
#PropertyName("Url")
private String myURL;
#PropertyName("Author")
private String myAuthor;
According to your edited question, you fileds are incorrect. Please how you Song class should look like:
public class Song {
private String author, song, url;
public Song() {}
public Song(String author, String song, String url) {
this.author = author;
this.song = song;
this.url = url;
}
public String getAuthor() { return author; }
public String getSong() { return song; }
public String getUrl() { return url; }
}
See the fields? Are named with the first letter lower case.

Can't successfully retrieve Spinner selected item text from database to fill contact list item in my app using cursor

My app has a registration screen for blood donors and the blood type field is a spinner. I save all the donor information in an SQLite database. Now I need to retrieve it and show it for a list showing all the registered blood donors with their blood types.
How can I do that?
I've attached all my code below. The main problems appear in RegisterActivity.java and DonorList.java.
RegisterActivity.java
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.Toast;
public class RegisterActivity extends AppCompatActivity {
EditText edtname, edtnumber;
Spinner spblood;
Button btnregister, btnlist;
public static SQLiteHelper sqLiteHelper;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
init();
Spinner spinner = findViewById(R.id.blood_selector);
// Create an ArrayAdapter using the string array and a default spinner layout
ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this,
R.array.blood_type, android.R.layout.simple_spinner_item);
// Specify the layout to use when the list of choices appears
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// Apply the adapter to the spinner
spinner.setAdapter(adapter);
sqLiteHelper = new SQLiteHelper(this, "Donors.sqlite", null, 1);
sqLiteHelper.queryData("CREATE TABLE IF NOT EXISTS DONORS (Id INTEGER PRIMARY KEY AUTOINCREMENT, name VARCHAR, number VARCHAR, blood VARCHAR)");
btnregister.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
try {
sqLiteHelper.insertData(
edtname.getText().toString().trim(),
edtnumber.getText().toString().trim(),
spblood
);
}
catch (Exception e) {
e.printStackTrace();
}
}
});
btnlist.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(RegisterActivity.this, DonorList.class);
startActivity(intent);
}
});
}
private void init() {
edtname = findViewById(R.id.name_input);
edtnumber = findViewById(R.id.numberinput);
spblood = findViewById(R.id.blood_selector);
btnregister = findViewById(R.id.register_button);
btnlist = findViewById(R.id.list_button);
}
}
DonorList.java
import android.database.Cursor;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.widget.ListView;
import android.widget.Spinner;
import java.util.ArrayList;
public class DonorList extends AppCompatActivity {
ListView listView;
ArrayList<Donor> list;
DonorListAdapter adapter = null;
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = (ListView) findViewById(R.id.contacts_list);
list = new ArrayList<>();
adapter = new DonorListAdapter(this, R.layout.activity_main, list);
listView.setAdapter(adapter);
Cursor cursor = RegisterActivity.sqLiteHelper.getData("SELECT * FROM DONORS");
list.clear();
while (cursor.moveToNext()) {
String name = cursor.getString(1);
String number = cursor.getString(2);
String blood = cursor.getString(3);
list.add(new Donor(name, number, blood));
}
adapter.notifyDataSetChanged();
}
}
Donor.java
import android.widget.Spinner;
public class Donor {
private String name;
private String number;
private Spinner blood;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getNumber() {
return number;
}
public void setNumber(String number) {
this.number = number;
}
public Spinner getBlood() {
return blood;
}
public void setBlood(Spinner blood) {
this.blood = blood;
}
public Donor(String name, String number, Spinner blood) {
this.name = name;
this.number = number;
this.blood = blood;
}
}
SQLiteHelper.java
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteStatement;
import android.widget.Spinner;
public class SQLiteHelper extends SQLiteOpenHelper {
public SQLiteHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version) {
super(context, name, factory, version);
}
public void queryData(String sql) {
SQLiteDatabase database = getWritableDatabase();
database.execSQL(sql);
}
public void insertData(String name, String number, Spinner blood) {
SQLiteDatabase database = getWritableDatabase();
String sql = "INSERT INTO DONORS (name, number, blood) values (?, ?, ?)";
SQLiteStatement statement = database.compileStatement(sql);
statement.clearBindings();
statement.bindString(1, name);
statement.bindString(2, number);
statement.bindString(3, blood.getSelectedItem().toString());
statement.executeInsert();
}
public Cursor getData(String sql) {
SQLiteDatabase database = getReadableDatabase();
return database.rawQuery(sql, null);
}
}
DonorListAdapter.java
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;
import java.util.ArrayList;
public class DonorListAdapter extends BaseAdapter {
private Context context;
private int layout;
private ArrayList<Donor> donorList;
public DonorListAdapter(Context context, int layout, ArrayList<Donor> donorList) {
this.context = context;
this.layout = layout;
this.donorList = donorList;
}
#Override
public int getCount() {
return donorList.size();
}
#Override
public Object getItem(int position) {
return donorList.get(position);
}
#Override
public long getItemId(int position) {
return position;
}
private class ViewHolder {
TextView txtname, txtnumber, txtblood;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
View row = convertView;
ViewHolder holder = new ViewHolder();
if (row == null) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
if (inflater != null) {
row = inflater.inflate(layout, null);
}
if (row != null) {
holder.txtname = row.findViewById(R.id.name_input);
}
if (row != null) {
holder.txtnumber = row.findViewById(R.id.numberinput);
}
if (row != null) {
holder.txtblood = (TextView) row.findViewById(R.id.blood_selector);
}
if (row != null) {
row.setTag(holder);
}
}
else {
holder = (ViewHolder) row.getTag();
}
Donor donor = donorList.get(position);
holder.txtname.setText(donor.getName());
holder.txtnumber.setText(donor.getNumber());
holder.txtblood.setText(donor.getBlood().toString());
return row;
}
}
activity_main.xml
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.lumen.dayem.blooddonor.MainActivity">
<ListView
android:id="#+id/contacts_list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:choiceMode="singleChoice">
</ListView>
</LinearLayout>
activity_register.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<EditText
android:id="#+id/name_input"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="#string/person_name"
android:ems="10"
android:inputType="textCapWords"
android:layout_marginBottom="5sp" />
<EditText
android:id="#+id/numberinput"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="#string/hint"
android:ems="10"
android:inputType="phone"
android:layout_marginBottom="5sp" />
<TextView
android:id="#+id/blood"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/blood_type"
android:layout_marginBottom="10sp"/>
<Spinner
android:id="#+id/blood_selector"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:entries="#array/blood_type"
android:prompt="#string/blood_select"
android:layout_marginBottom="5sp"/>
<Button
android:id="#+id/register_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/register" />
<Button
android:id="#+id/list_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/show_donors" />
</LinearLayout>
contact_item.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="#+id/contact_name"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="#string/contact_name"
android:textSize="22sp"/>
<TextView
android:id="#+id/contact_number"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textAppearance="?android:textAppearanceSmall"
android:text="#string/contact_number"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginLeft="29sp"
android:layout_marginStart="29sp"
android:layout_marginTop="31sp" />
<TextView
android:id="#+id/contact_blood"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textAppearance="?android:textAppearanceMedium"
android:text="#string/blood_type"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginLeft="300sp"
android:layout_marginStart="300sp"
android:layout_marginTop="30sp"/>
</RelativeLayout>

Your class Donor seems to have a field blood of type Spinner. I changed the type to String because a data class should not contain any Views:
public class Donor
{
private String name;
private String number;
private String blood;
// Getters and Setters here...
public Donor(String name, String number, String blood) {
this.name = name;
this.number = number;
this.blood = blood;
}
}
The SQLiteHelper should have a static getInstance() method so you can avoid having it as a static field in RegisterActivity. Also, I think that the database setup should be encapsulated. The Activity does not need to know anything about the database implementation. So I moved the DDL to the SQLiteHelper's onCreate() and dropped queryData(). For the same reason, I changed getData(String sql) to getDonors(). Lastly, insertData() should take data as parameters not Views. So one should not pass the Spinner but the selected item's value.
My version of SQLiteHelper.java:
public class SQLiteHelper extends SQLiteOpenHelper{
private static SQLiteHelper sqliteHelper;
private static String dbName = "Donors.sqlite";
private static int version = 1;
private static final String CREATE_TABLE_DONORS = "CREATE TABLE IF NOT EXISTS DONORS (Id INTEGER PRIMARY KEY AUTOINCREMENT, name VARCHAR, number VARCHAR, blood VARCHAR)";
/**
* We use the application Context under the hood because this helps to avoid Exceptions
* #param ctx
*/
private SQLiteHelper(Context ctx){
super(ctx.getApplicationContext(), dbName, null, version);
}
/**
* SQLiteHelper as a Singleton
* #param ctx any Context
* #return x
*/
public static SQLiteHelper getInstance(Context ctx)
{
if(sqliteHelper == null){
sqliteHelper = new SQLiteHelper(ctx);
}
return sqliteHelper;
}
#Override
public void onCreate(SQLiteDatabase db)
{
db.execSQL(CREATE_TABLE_DONORS);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)
{
// necessary if you have a new database version
}
public void insertData(String name, String number, String blood) {
SQLiteDatabase database = getWritableDatabase();
String sql = "INSERT INTO DONORS (name, number, blood) values (?, ?, ?)";
SQLiteStatement statement = database.compileStatement(sql);
statement.clearBindings();
statement.bindString(1, name);
statement.bindString(2, number);
statement.bindString(3, blood);
statement.executeInsert();
}
public Cursor getDonors() {
String sql = "SELECT * FROM DONORS";
SQLiteDatabase database = getReadableDatabase();
return database.rawQuery(sql, null);
}
}
The updated RegisterActivity.java (note that I got rid of the local variable spinner and only used spblood):
public class RegisterActivity extends AppCompatActivity
{
private EditText edtname, edtnumber;
private Spinner spblood;
private Button btnregister, btnlist;
private SQLiteHelper sqLiteHelper;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
init();
ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this,
R.array.blood_type, android.R.layout.simple_spinner_item);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spblood.setAdapter(adapter);
sqLiteHelper = SQLiteHelper.getInstance(this);
btnregister.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
try {
sqLiteHelper.insertData(
edtname.getText().toString().trim(),
edtnumber.getText().toString().trim(),
spblood.getSelectedItem().toString()
);
}
catch (Exception e) {
e.printStackTrace();
}
}
});
btnlist.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(RegisterActivity.this, DonorList.class);
startActivity(intent);
}
});
}
private void init() {
edtname = findViewById(R.id.name_input);
edtnumber = findViewById(R.id.numberinput);
spblood = findViewById(R.id.blood_selector);
btnregister = findViewById(R.id.register_button);
btnlist = findViewById(R.id.list_button);
}
}
The changes to DonorList and the Adapter are due to the changes I made to SQLiteHelper and Donor. In addition to that, you need to pass the resource id of the list row to the Adapter's Constructor not the resource id of the Activity's layout. Similarly, the R.id.... values for the TextViews in the list row have to match those in contact_item.xml
DonorList.java
public class DonorList extends AppCompatActivity
{
private ListView listView;
private ArrayList<Donor> list;
private DonorListAdapter adapter = null;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = (ListView) findViewById(R.id.contacts_list);
list = new ArrayList<>();
adapter = new DonorListAdapter(this, R.layout.contact_item, list);
listView.setAdapter(adapter);
Cursor cursor = SQLiteHelper.getInstance(this).getDonors();
list.clear();
while (cursor.moveToNext()) {
String name = cursor.getString(1);
String number = cursor.getString(2);
String blood = cursor.getString(3);
list.add(new Donor(name, number, blood));
}
adapter.notifyDataSetChanged();
}
}
And finally, the Adapter:
public class DonorListAdapter extends BaseAdapter
{
private Context context;
private int layout;
private ArrayList<Donor> donorList;
public DonorListAdapter(Context context, int layout, ArrayList<Donor> donorList) {
this.context = context;
this.layout = layout;
this.donorList = donorList;
}
#Override
public int getCount() {
return donorList.size();
}
#Override
public Object getItem(int position) {
return donorList.get(position);
}
#Override
public long getItemId(int position) {
return position;
}
private class ViewHolder {
TextView txtname, txtnumber, txtblood;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
View row = convertView;
if (row == null) {
ViewHolder holder = new ViewHolder();
row = LayoutInflater.from(context).inflate(layout, null);
holder.txtname = (TextView)row.findViewById(R.id.contact_name);
holder.txtnumber = (TextView)row.findViewById(R.id.contact_number);
holder.txtblood = (TextView) row.findViewById(R.id.contact_blood);
row.setTag(holder);
}
ViewHolder viewHolder = (ViewHolder) row.getTag();
Donor donor = donorList.get(position);
viewHolder.txtname.setText(donor.getName());
viewHolder.txtnumber.setText(donor.getNumber());
viewHolder.txtblood.setText(donor.getBlood());
return row;
}
}
Enjoy!

ListView Items aren't displaying on Main Activity

I'm a beginner in android development. I'm trying to send data from an ArrayList of Type Workout Item to the MainActivity using an Adapter, but I don't understand base adapters very well. Here is my code:
WorkoutActivity.java:
import java.util.ArrayList;
import java.util.List;
import android.app.Activity;
import android.app.FragmentManager;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.os.Bundle;
import android.os.SystemClock;
import android.preference.PreferenceManager;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.Chronometer;
import android.widget.TextView;
public class WorkoutActivity extends Activity {
WorkoutItemAdapter workoutItemAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_workout);
}
public class WorkoutItemAdapter extends BaseAdapter{
int rowCount = 1;
List<WorkoutItem> workoutsList = getDataForListView();
public WorkoutItem getWorkout(int position)
{
return workoutsList.get(position);
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
if(convertView == null){
LayoutInflater inflater = (LayoutInflater) WorkoutActivity.this.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.workout_item, parent, false);
}
TextView workoutNum = (TextView) convertView.findViewById(R.id.workout_col);
TextView workoutTime = (TextView) convertView.findViewById(R.id.time_col);
WorkoutItem workout = workoutsList.get(position);
workoutNum.setText(workout.workoutNum);
workoutTime.setText(workout.time);
return convertView;
}
#Override
public int getCount() {
return workoutsList.size();
// TODO Auto-generated method stub
}
#Override
public WorkoutItem getItem(int position) {
// TODO Auto-generated method stub
return workoutsList.get(position);
}
#Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
public void addRow() {
rowCount++;
notifyDataSetChanged();
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.workout, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
#Override
public void onBackPressed() {
moveTaskToBack(true);
}
public List<WorkoutItem> getDataForListView()
{
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
String workoutTime = prefs.getString("Workout Time", "");
List<WorkoutItem> workoutsList = new ArrayList<WorkoutItem>();
for(int i = 0; i < (workoutsList.size() + 1); i++)
{
WorkoutItem workout = new WorkoutItem();
workout.workoutNum = "Workout " + (i+1);
workout.time = workoutTime;
workoutsList.add(workout);
}
return workoutsList;
}
public void startAndStopTimer(View view)
{
long totalTime = 0;
Button startAndStop = (Button) findViewById(R.id.button1);
Chronometer c = (Chronometer) findViewById(R.id.chronometer1);
if(startAndStop.getText().equals("Start"))
{
c.setBase(SystemClock.elapsedRealtime() + totalTime);
c.start();
startAndStop.setText("Pause");
}
else
{
totalTime = c.getBase() - SystemClock.elapsedRealtime();
c.stop();
startAndStop.setText("Start");
}
}
public void save(View view)
{
// create broadcast receiver saying ...saved.
// Add ArrayList value to arrayList
Chronometer timer = (Chronometer) findViewById(R.id.chronometer1);
SharedPreferences timerSettings = PreferenceManager.getDefaultSharedPreferences(this);
Editor editor = timerSettings.edit();
editor.putString("Workout Time", timer.getText().toString());
editor.commit();
// go back to main activity.
Intent intent = new Intent(WorkoutActivity.this, OverviewActivity.class);
startActivity(intent);
finish();
}
public void cancel(View view)
{
// go back to main activity
Intent intent = new Intent(WorkoutActivity.this, OverviewActivity.class);
startActivity(intent);
finish();
}
}
OverviewActivity.java:
import edu.uark.csce.razorrunner.WorkoutActivity.WorkoutItemAdapter;
import android.app.Activity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.ListView;
import android.widget.TextView;
public class OverviewActivity extends Activity{
WorkoutItemAdapter workoutAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_overview);
LoadPreferences();
LoadListView();
}
private void LoadListView() {
// TODO Auto-generated method stub
ListView workoutList = (ListView) findViewById(R.id.workout_list);
workoutList.setAdapter(workoutAdapter);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.overview, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
private void LoadPreferences()
{
SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
String Name = sharedPreferences.getString("Name", "");
TextView textView = (TextView) findViewById(R.id.textView2);
textView.setText(Name);
}
public void openWorkoutActivity(View view)
{
Intent intent = new Intent(OverviewActivity.this, WorkoutActivity.class);
startActivity(intent);
finish();
}
public void openProfileActivity(View view)
{
Intent intent = new Intent(OverviewActivity.this, ProfileActivity.class);
startActivity(intent);
finish();
}
public void openHistoryActivity(View view)
{
Intent intent = new Intent(OverviewActivity.this, HistoryActivity.class);
startActivity(intent);
finish();
}
}
activity_overview.xml:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/LinearLayout1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="edu.uark.csce.razorrunner.OverviewActivity" >
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<Button
android:id="#+id/profileButton"
android:layout_width="80dp"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:onClick="openProfileActivity"
android:text="Profile" />
<TextView
android:id="#+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
android:text="Name"
android:textAppearance="?android:attr/textAppearanceLarge" />
</RelativeLayout>
<ListView
android:id="#+id/workout_list"
android:layout_width="wrap_content"
android:layout_height="195dp"
android:layout_weight="0.19" >
</ListView>
<Button
android:id="#+id/startNewWorkout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="0"
android:onClick="openWorkoutActivity"
android:text="Start New Workout!"
android:typeface="sans" />
</LinearLayout>
activity_workout.xml:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="edu.uark.csce.razorrunner.WorkoutActivity" >
<Button
android:id="#+id/Button01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="#+id/button2"
android:layout_alignBottom="#+id/button2"
android:layout_alignRight="#+id/button1"
android:text="Cancel"
android:onClick="cancel" />
<Button
android:id="#+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_toLeftOf="#+id/Button01"
android:text="Save"
android:onClick="save" />
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="#+id/Button01"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_marginRight="22dp"
android:text="Start"
android:onClick="startAndStopTimer" />
<TextView
android:id="#+id/time_col"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/textView2"
android:layout_alignParentTop="true"
android:text="New Workout"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:id="#+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_below="#+id/time_col"
android:layout_marginTop="18dp"
android:text="Calories Burned"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:id="#+id/TextView01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/textView2"
android:layout_below="#+id/textView2"
android:layout_marginTop="14dp"
android:text="Duration"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:id="#+id/TextView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="#+id/textView2"
android:layout_alignBottom="#+id/textView2"
android:layout_alignRight="#+id/button1"
android:layout_toRightOf="#+id/button2"
android:ems="10"
android:text="0"
android:textAppearance="?android:attr/textAppearanceLarge">
<requestFocus />
</TextView>
<Chronometer
android:id="#+id/chronometer1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBottom="#+id/TextView01"
android:layout_alignLeft="#+id/TextView1"
android:layout_alignRight="#+id/TextView1"
android:text="Chronometer" />
</RelativeLayout>
I'd like to show the workout number and duration for each list item every time I click Save, but currently all I get is a blank ListView every time I click Save. Any help and/or additional sources on this topic would be useful.

I hope two mistakes you made.
public List<WorkoutItem> getDataForListView()
{
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
String workoutTime = prefs.getString("Workout Time", "");
List<WorkoutItem> workoutsList = new ArrayList<WorkoutItem>();
for(int i = 0; i < (workoutsList.size() + 1); i++)
{
WorkoutItem workout = new WorkoutItem();
workout.workoutNum = "Workout " + (i+1);
workout.time = workoutTime;
workoutsList.add(workout);
}
return workoutsList;
}
I guess you are trying to add data to list view. Since you are creating new List using
List<WorkoutItem> workoutsList = new ArrayList<WorkoutItem>();
workoutsList.size() will return zero. your loop iterates till list size+1. (only one time )
then you need to pass the List from WorkoutActivity to OverviewActivity.
change WorkoutActivity insert following code
public class WorkoutActivity extends Activity {
WorkoutItemAdapter workoutItemAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_workout);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.workout, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
#Override
public void onBackPressed() {
moveTaskToBack(true);
}
public List<WorkoutItem> getDataForListView() {
SharedPreferences prefs = PreferenceManager
.getDefaultSharedPreferences(this);
String workoutTime = prefs.getString("Workout Time", "");
List<WorkoutItem> workoutsList = new ArrayList<WorkoutItem>();
for (int i = 0; i < (10+ 1); i++) {
WorkoutItem workout = new WorkoutItem();
workout.workoutNum = "Workout " + (i + 1);
workout.time = workoutTime;
workoutsList.add(workout);
}
return workoutsList;
}
public void startAndStopTimer(View view) {
long totalTime = 0;
Button startAndStop = (Button) findViewById(R.id.button1);
Chronometer c = (Chronometer) findViewById(R.id.chronometer1);
if (startAndStop.getText().equals("Start")) {
c.setBase(SystemClock.elapsedRealtime() + totalTime);
c.start();
startAndStop.setText("Pause");
} else {
totalTime = c.getBase() - SystemClock.elapsedRealtime();
c.stop();
startAndStop.setText("Start");
}
}
public void save(View view) {
// create broadcast receiver saying ...saved.
// Add ArrayList value to arrayList
Chronometer timer = (Chronometer) findViewById(R.id.chronometer1);
SharedPreferences timerSettings = PreferenceManager
.getDefaultSharedPreferences(this);
Editor editor = timerSettings.edit();
editor.putString("Workout Time", timer.getText().toString());
editor.commit();
// go back to main activity.
Intent intent = new Intent(WorkoutActivity.this, OverviewActivity.class);
intent.putStringArrayListExtra("stock_list", getDataForListView());
startActivity(intent);
finish();
}
public void cancel(View view) {
// go back to main activity
Intent intent = new Intent(WorkoutActivity.this, OverviewActivity.class);
intent.putStringArrayListExtra("stock_list", getDataForListView());
startActivity(intent);
finish();
}
}
and OverviewActivity to this
public class OverviewActivity extends Activity{
List<WorkoutItem> workList;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_overview);
Intent i = getIntent();
workList = i.getStringArrayListExtra("stock_list");
LoadPreferences();
LoadListView();
}
private void LoadListView() {
// TODO Auto-generated method stub
ListView workoutList = (ListView) findViewById(R.id.workout_list);
WorkoutItemAdapter workoutAdapter= new WorkoutItemAdapter(workList);
workoutList.setAdapter(workoutAdapter);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.overview, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
private void LoadPreferences()
{
SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
String Name = sharedPreferences.getString("Name", "");
TextView textView = (TextView) findViewById(R.id.textView2);
textView.setText(Name);
}
public void openWorkoutActivity(View view)
{
Intent intent = new Intent(OverviewActivity.this, WorkoutActivity.class);
startActivity(intent);
finish();
}
public void openProfileActivity(View view)
{
Intent intent = new Intent(OverviewActivity.this, ProfileActivity.class);
startActivity(intent);
finish();
}
public void openHistoryActivity(View view)
{
Intent intent = new Intent(OverviewActivity.this, HistoryActivity.class);
startActivity(intent);
finish();
}
public class WorkoutItemAdapter extends BaseAdapter{
int rowCount = 1;
List<WorkoutItem> workoutsList ;
public WorkoutItemAdapter( List<WorkoutItem> list) {
workoutsList=list;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
if(convertView == null){
LayoutInflater inflater = (LayoutInflater) WorkoutActivity.this.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.workout_item, parent, false);
}
TextView workoutNum = (TextView) convertView.findViewById(R.id.workout_col);
TextView workoutTime = (TextView) convertView.findViewById(R.id.time_col);
WorkoutItem workout = workoutsList.get(position);
workoutNum.setText(workout.workoutNum);
workoutTime.setText(workout.time);
return convertView;
}
#Override
public int getCount() {
return workoutsList.size();
// TODO Auto-generated method stub
}
#Override
public WorkoutItem getItem(int position) {
// TODO Auto-generated method stub
return workoutsList.get(position);
}
#Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
public void addRow() {
rowCount++;
notifyDataSetChanged();
}
}
}
try these code. I have not yet tried, hope will works fine.

So I assume OverviewActivity.java is your main Activity which in return opens WorkoutActivity ?

you haven't initialise workoutAdapter...only declared....
hence workoutAdapter is null....which means the size of adapter is 0 ...which means no rows for list view...
before setting the adapter to listview ..you must have to initialize workoutAdapter
i.e.
workoutAdapter=new WorkoutItemAdapter(getDataForListView());
create the adaper contructor and pass the list array
public class WorkoutItemAdapter extends BaseAdapter{
int rowCount = 1; //don't know about that
List<WorkoutItem> workoutsList;
public WorkoutItemAdapter(List<WorkoutItem> tmp)
{
this.workoutsList=tmp; //setting the list array to datamember of this adapter
}

In WorkOutItemAdapter List<WorkoutItem> workoutsList = getDataForListView();
// check the size of the list is zero or null
In WorkOutItemActivity you do like this
WorkoutItemAdapter workoutItemAdapter = new WorkoutItemAdapter();
ListView workoutList = (ListView) findViewById(R.id.workout_list);
workoutList.setAdapter(workoutAdapter);*

no such column _id Android,Java,SQL

I'm pretty new to Java and Android apps, just started several weeks ago, everything went pretty well until now, when I stuck for several hours with a problem I cannot resolve, even with checking dozens of threads here.
I'm working on pretty simple android app that is supposed to show movies and years from a database, with a possibility to add record, show them all, search by a year or title. I stopped on a problem with
no such column _id (code 1): , while compiling SELECT _id, title, year FROM movies
I will be grateful for any help.
There are my files :
MainActivity
package com.example.imdbproject;
import java.util.ArrayList;
import java.util.List;
import android.os.Bundle;
import android.app.Activity;
import android.support.v4.widget.SimpleCursorAdapter;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.Button;
import android.widget.ListView;
import android.content.ContentValues;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class MainActivity extends Activity {
ListView moviesList;
Button searchYear;
Button searchTitle;
Button showAll;
Button addbtn;
Cursor cursor;
adapter adapter_ob;
MySQLiteHelper helper_ob;
SQLiteDatabase db_ob;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
InitDataBase();
moviesList = (ListView)findViewById(R.id.listView1);
searchYear = (Button)findViewById(R.id.buttonYear);
searchTitle =(Button)findViewById(R.id.buttonTitle);
addbtn = (Button)findViewById(R.id.buttonAdd);
showAll = (Button)findViewById(R.id.buttonShowAll);
adapter_ob = new adapter(this);
String[] from = { helper_ob.KEY_TITLE, helper_ob.KEY_YEAR };
int[] to = { R.id.tv_title, R.id.tv_year };
//PROBLEM
//cursor = adapter_ob.queryName();
//PROBLEM
//SimpleCursorAdapter cursorAdapter = new SimpleCursorAdapter(this, R.layout.row, cursor, from, to, 1);
/*
moviesList.setAdapter(cursorAdapter);
moviesList.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView arg0, View arg1, int arg2, long arg3) {
Bundle passdata = new Bundle();
Cursor listCursor = (Cursor) arg0.getItemAtPosition(arg2);
int nameId = listCursor.getInt(listCursor.getColumnIndex(helper_ob.KEY_ID));
passdata.putInt("keyid", nameId);
Intent passIntent = new Intent(MainActivity.this,EditActivity.class);
passIntent.putExtras(passdata);
startActivity(passIntent);
}
});
*/
addbtn.setOnClickListener(new OnClickListener()
{
public void onClick(View arg0)
{
Intent addsomemoviesIntent = new Intent(MainActivity.this, AddSomeMovies.class);
startActivity(addsomemoviesIntent);
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public void InitDataBase() {
MySQLiteHelper sqh = new MySQLiteHelper(this);
SQLiteDatabase sqdb = sqh.getWritableDatabase();
long result = sqh.addMovie("movietitle", "year");
}
}
adapter.java
package com.example.imdbproject;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.content.ContentValues;
import android.database.Cursor;
public class adapter {
SQLiteDatabase database_ob;
MySQLiteHelper openHelper_ob;
Context context;
public adapter(Context c)
{
context = c;
}
public adapter openToRead()
{
openHelper_ob = new MySQLiteHelper(context,
MySQLiteHelper.DATABASE_NAME, null, MySQLiteHelper.DATABASE_VERSION);
database_ob = openHelper_ob.getWritableDatabase();
return this;
}
public adapter openToWrite()
{
openHelper_ob = new MySQLiteHelper(context,
MySQLiteHelper.DATABASE_NAME, null, MySQLiteHelper.DATABASE_VERSION);
database_ob = openHelper_ob.getWritableDatabase();
return this;
}
public void Close()
{
database_ob.close();
}
public long insertDetails(String title, String year)
{
ContentValues cv = new ContentValues();
cv.put(MySQLiteHelper.KEY_TITLE, title);
cv.put(MySQLiteHelper.KEY_YEAR, year);
openToWrite();
long val = database_ob.insert(MySQLiteHelper.TABLE_NAME, null, cv);
Close();
return val;
}
public Cursor queryName()
{
String[] cols = { MySQLiteHelper.KEY_ID, MySQLiteHelper.KEY_TITLE,
MySQLiteHelper.KEY_YEAR };
openToWrite();
Cursor c = database_ob.query(MySQLiteHelper.TABLE_NAME, cols, null, null, null, null, null);
return c;
}
public Cursor queryAll(int nameId)
{
String[] cols = { MySQLiteHelper.KEY_ID, MySQLiteHelper.KEY_TITLE, MySQLiteHelper.KEY_YEAR };
openToWrite();
Cursor c = database_ob.query(MySQLiteHelper.TABLE_NAME, cols, MySQLiteHelper.KEY_ID + "=" + nameId, null,null,null,null);
return c;
}
}
MySQLiteHelper
package com.example.imdbproject;
import java.util.LinkedList;
import java.util.List;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class MySQLiteHelper extends SQLiteOpenHelper {
public static final String DATABASE_NAME = "movie_data.db";
public static final int DATABASE_VERSION = 1;
public static final String TABLE_NAME = "movies";
public static final String KEY_ID = "_id";
public static final String KEY_TITLE = "title";
public static final String KEY_YEAR = "year";
public static final String SCRIPT = "Create table " + TABLE_NAME + " ("
+ KEY_ID + " integer primary key autoincrement, " + KEY_TITLE
+ " text, " + KEY_YEAR + " text);";
public MySQLiteHelper(Context context)
{
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
public MySQLiteHelper(Context context, String name, CursorFactory factory, int version)
{
super(context, name, factory, version);
}
#Override public void onCreate(SQLiteDatabase db)
{
db.execSQL(SCRIPT);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)
{
db.execSQL("DROP TABLE " + TABLE_NAME);
onCreate(db);
}
public long addMovie(String movietitle, String year){
ContentValues cv = new ContentValues();
cv.put(KEY_TITLE, movietitle);
cv.put(KEY_YEAR, year);
SQLiteDatabase sd = getWritableDatabase();
long result = sd.insert(TABLE_NAME, KEY_TITLE, cv);
return result;
}
}
AddSomeMovies
package com.example.imdbproject;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
public class AddSomeMovies extends Activity {
adapter adapter;
MySQLiteHelper helper;
EditText titleEdit, yearEdit;
Button addButton;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_add_some_movies);
titleEdit = (EditText)findViewById(R.id.etTitle);
yearEdit = (EditText)findViewById(R.id.etYear);
addButton = (Button)findViewById(R.id.button1);
adapter = new adapter(this);
addButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View arg0)
{
String titleValue = titleEdit.getText().toString();
String yearValue = yearEdit.getText().toString();
long val = adapter.insertDetails(titleValue, yearValue);
finish();
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.add_some_movies, menu);
return true;
}
}
activity_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/black"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<Button
android:id="#+id/buttonShowAll"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/buttonTitle"
android:layout_below="#+id/buttonTitle"
android:text="#string/showall"
/>
<Button
android:id="#+id/buttonYear"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="#+id/buttonTitle"
android:layout_alignBottom="#+id/buttonTitle"
android:layout_alignParentRight="true"
android:text="#string/yearsearch"
/>
<Button
android:id="#+id/buttonTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:text="#string/titlesearch"
/>
<Button
android:id="#+id/buttonAdd"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="#+id/buttonShowAll"
android:layout_alignBottom="#+id/buttonShowAll"
android:layout_toRightOf="#+id/buttonShowAll"
android:text="#string/add"
android:onClick="add" />
<Button
android:id="#+id/buttonOk"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignRight="#+id/buttonYear"
android:layout_below="#+id/buttonYear"
android:enabled="false"
android:onClick="ok"
android:text="#string/ok"
android:visibility="invisible" />
<EditText
android:id="#+id/edittext"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/buttonShowAll"
android:layout_centerHorizontal="true"
android:ems="10"
android:hint="#string/searcheditview" />
<ListView
android:id="#+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/buttonShowAll"
android:layout_below="#+id/edittext" >
</ListView>
</RelativeLayout>
row.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<TextView
android:id="#+id/tv_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<TextView
android:id="#+id/tv_year"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="20dp" />
</LinearLayout>

SORTED!
At least I think so. Problem disappeared when I changed database version to 2 from 1. So I can guess that it needs more attention now.

try following
public static final String KEY_ID = BaseColumns._ID;
instead of
public static final String KEY_ID = "_id";