How to insert and retrieve data display button using sqlite

How to insert and retrieve data display button using sqlite - java

I cant't get all data to display in button when click on button get. please help me.
public class DBHelper extends SQLiteOpenHelper {
private static final int VERSION = 1;
private static final String DATABASE = "Test";
private static final String TABLE_NAME = "savedata";
private static final String KEY_ID = "id";
private static final String KEY_NAME = "name";
private static final String KEY_SEX = "sex";
public DBHelper(Context context) {
super(context, DATABASE, null,VERSION);
}
#Override
public void onCreate(SQLiteDatabase db) {
String sql = "CREATE TABLE IF NOT EXISTS " +TABLE_NAME + "("
+ KEY_ID + " INTEGER PRIMARY KEY AUTOINCREMENT,"
+ KEY_NAME + " TEXT,"
+ KEY_SEX + " TEXT)";
db.execSQL(sql);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS" +TABLE_NAME);
onCreate(db);
}
public void Insertdata(Data data){
SQLiteDatabase db = getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_NAME, data.getName());
values.put(KEY_SEX, data.getSex());
db.insert(TABLE_NAME, null, values);
}
public List<Data> getAllData(){
List<Data> listData = new ArrayList<Data>();
SQLiteDatabase db = this.getWritableDatabase();
Cursor c = db.rawQuery("SELECT * FROM " +TABLE_NAME, null);
if (c.moveToFirst()){
do {
Data data = new Data();
data.setId(c.getInt(0));
data.setName(c.getString(1));
data.setSex(c.getString(2));
listData.add(data);
}while (c.moveToNext());
}
return listData;
}
}
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
name = (EditText)findViewById(R.id.edit_name);
sex = (EditText)findViewById(R.id.edit_sex);
btn_get = (Button)findViewById(R.id.btn_get);
btn_name = (Button)findViewById(R.id.btn_name);
btn_sex = (Button)findViewById(R.id.btn_sex);
btn_id = (Button)findViewById(R.id.btn_id);
db = new DBHelper(this);
_name = name.getText().toString();
_sex = sex.getText().toString();
data = new Data(_name,_sex);
btn_save =( Button)findViewById(R.id.btn_save);
SaveData();
getData();
}
public void SaveData(){
btn_save.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
try{
db.Insertdata(data);
Toast.makeText(getApplicationContext(), "SuccessFull",Toast.LENGTH_SHORT).show();
}catch (Exception e){
Toast.makeText(getApplicationContext(), e.toString(), Toast.LENGTH_SHORT).show();
}
}
});
}
public void getData(){
btn_get.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
try {
if (currentData == null){
Toast.makeText(getApplicationContext(),"Null", Toast.LENGTH_SHORT).show();
}else {
currentData = db.getAllData();
btn_id.setText(String.valueOf(data.getId()));
btn_name.setText(data.getName());
btn_sex.setText(data.getSex());
}
}catch (Exception e){
Toast.makeText(getApplicationContext(), e.toString(), Toast.LENGTH_SHORT).show();
}
}
});
}

You've messed up badly. That's all I can suggest-
1. Create a class (for example "MyClass") that will extend AppCompatActivity and contains the view.
2. You've already created a class named DBHelper for your Database manipulation. It extends SQLiteOpenHelper.
3. Create object of DBHelper class inside the onCreate method of MyClass and access your database. onCreate method in MyClass will be looking similar to this-
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
name = (EditText)findViewById(R.id.edit_name);
sex = (EditText)findViewById(R.id.edit_sex);
btn_get = (Button)findViewById(R.id.btn_get);
btn_name = (Button)findViewById(R.id.btn_name);
btn_sex = (Button)findViewById(R.id.btn_sex);
btn_id = (Button)findViewById(R.id.btn_id);
db = new DBHelper(this);
_name = name.getText().toString();
_sex = sex.getText().toString();
data = new Data(_name,_sex);
btn_save =( Button)findViewById(R.id.btn_save);
btn_save.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
try{
db.Insertdata(data);
Toast.makeText(getApplicationContext(), "SuccessFull",Toast.LENGTH_SHORT).show();
}catch (Exception e){
Toast.makeText(getApplicationContext(), e.toString(), Toast.LENGTH_SHORT).show();
}
}
});
btn_get.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
try {
if (currentData == null){
Toast.makeText(getApplicationContext(),"Null", Toast.LENGTH_SHORT).show();
}else {
currentData = db.getAllData();
btn_id.setText(String.valueOf(data.getId()));
btn_name.setText(data.getName());
btn_sex.setText(data.getSex());
}
}catch (Exception e){
Toast.makeText(getApplicationContext(), e.toString(), Toast.LENGTH_SHORT).show();
}
}
});
}
Hope that, this might help.

Related

SQL Lite Data not being inserted (Android Studio in java)

I want to insert data from user input on the click of a button but it does not get added. In my addData function it is always returning false. I don't seem to understand why this is happening nor do I have any clue where the error is since my code isn't producing any.
Here is my Database Helper code:
private static final String TAG = "DatabaseHelper";
private static final String TABLE_NAME = "nutrition_table";
private static final String COL1 = "ID";
private static final String COL2 = "food";
private static final String COL3 = "calories";
DatabaseHelper(Context context) {
super(context, TABLE_NAME, null, 1);
}
#Override
public void onCreate(SQLiteDatabase DB) {
String createTable = "CREATE TABLE " + TABLE_NAME + " (ID INTEGER PRIMARY KEY AUTOINCREMENT, " +
COL2 + " TEXT" + COL3 + " ,TEXT)" ;
DB.execSQL(createTable);
}
#Override
public void onUpgrade(SQLiteDatabase DB, int i, int i1) {
DB.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
onCreate(DB);
}
public boolean addData(String item) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put(COL2, item);
contentValues.put(COL3, item);
Log.d(TAG, "addData: Adding " + item + "to" + TABLE_NAME);
long res = db.insert(TABLE_NAME, null, contentValues);
if (res == -1) {
return false;
} else {
return true;
}
}
public Cursor getData() {
SQLiteDatabase db = this.getWritableDatabase();
String query = "SELECT * FROM " + TABLE_NAME;
Cursor data = db.rawQuery(query, null);
return data;
}
}
Here is my addActivity code:
DatabaseHelper mDbhelper;
TextView addFood, addCals;
Button addEntry, deleteEntry;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_add);
addFood = findViewById(R.id.addFoodItemTextView);
addCals = findViewById(R.id.addCaloriesTextView);
addEntry = findViewById(R.id.addBtn);
deleteEntry = findViewById(R.id.deleteBtn);
mDbhelper = new DatabaseHelper(this);
addEntry.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
String foodEntry = addFood.getText().toString();
String calsEntry = addCals.getText().toString();
if (foodEntry.length() != 0) {
addData(foodEntry);
addFood.setText("");
} else {
toastMessage("You have to add data in the food/meal text field!");
}
if (calsEntry.length() != 0) {
addData(calsEntry);
addCals.setText("");
} else {
toastMessage("You have to add data in the calorie text field");
}
}
});
}
public void addData(String newEntry) {
boolean insertData = mDbhelper.addData(newEntry);
if (insertData) {
toastMessage("Added to entries");
} else {
toastMessage("Something went wrong");
}
}
private void toastMessage(String message) {
Toast.makeText(this, message, Toast.LENGTH_SHORT).show();
}
}
Here is the code where the data is supposed to be displayed:
private final static String TAG = "listData";
DatabaseHelper dbHelper;
private ListView displayData;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_view_entries);
displayData = findViewById(R.id.listData);
dbHelper = new DatabaseHelper(this);
populateListView();
}
private void populateListView() {
Log.d(TAG, "populateListView: Displaying data in the ListView.");
Cursor data = dbHelper.getData();
ArrayList<String> listData = new ArrayList<>();
while(data.moveToNext()) {
listData.add(data.getString(1));
listData.add(data.getString(2));
}
ListAdapter adapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, listData);
displayData.setAdapter(adapter);
}
}
Keep in mind that I am using an intent to view the entries (When the user clicks the button it brings him to the View entries page). I'm not sure where my code went wrong. Any help is greatly appreciated.
Thanks!

Android Studio + Database - Multiple check data to insert data if not exists

I'm having a problem with my code. I don't know how to check multiple columns in the database to insert different data on every not existing data.
For example:
1st input
Name: Raymond Jay Berin
Event: INTRAMURALS
FACILITATOR: CSG
2nd input
Name: Raymond Jay Berin
Event: LOVE SYMPOSIUM
FACILITATOR: DSSC
the thing here is that. Raymond Jay Berin already existed in the database, but I want Raymond Jay Berin will be inserted into a different event...
also, I already tried to create multiple tables but my project crashes when I click the attendance button to add data.
Code for DatabaseHelper.class:
public class DatabaseHelper extends SQLiteOpenHelper {
public static final String DATABASE_NAME = "attendance.sqlite";
public static final String TABLE_NAME = "attendance";
public static final String COL_1 = "ID";
public static final String COL_2 = "FULLNAME";
public static final String COL_EVENT_2 = "EVENT_NAME";
public static final String COL_EVENT_3 = "FACILITATOR_NAME";
public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, 1);
}
#Override
public void onCreate(SQLiteDatabase db) {
//ATTENDANCE
db.execSQL(" create table " + TABLE_NAME + "(ID INTEGER PRIMARY KEY AUTOINCREMENT, " +
"FULLNAME TEXT NOT NULL, EVENT_NAME TEXT NOT NULL, FACILITATOR_NAME TEXT NOT NULL)");
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
//ATTENDANCE
db.execSQL(" DROP TABLE IF EXISTS "+TABLE_NAME );
//recreate
onCreate(db);
}
//ATTENDANCE
public boolean insertData (String fullname, String event, String facilitator){
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put(COL_2,fullname);
contentValues.put(COL_EVENT_2,event);
contentValues.put(COL_EVENT_3,facilitator);
long result = db.insert(TABLE_NAME,null,contentValues);
if(result == -1)
return false;
else
return true;
}
public Cursor getAllData() {
SQLiteDatabase db = this.getWritableDatabase();
Cursor res = db.rawQuery("select * from "+TABLE_NAME,null);
return res;
}
public boolean checkIfRecordExist(String nameOfTable,String columnName,String columnValue) {
SQLiteDatabase db = null;
try {
db = this.getReadableDatabase();
Cursor cursor = db.rawQuery("SELECT "+columnName+" FROM "+nameOfTable+" WHERE "+columnName+"='"+columnValue+"'",null);
if (cursor.moveToFirst()) {
db.close();
Log.d("Record Already Exists", "Table is:" + nameOfTable + " ColumnName:" + columnName);
return true;//record Exists
}
Log.d("New Record ", "Table is:" + nameOfTable + " ColumnName:" + columnName + " Column Value:" + columnValue);
db.close();
} catch (Exception errorException) {
Log.d("Exception occured", "Exception occured " + errorException);
db.close();
}
return false;
} }
Code for the Attendance.java class
public class Attendance extends AppCompatActivity implements CompoundButton.OnCheckedChangeListener {
DatabaseHelper myDb;
EditText fname , eventname, faciname;
Button attendance;
Button view;
Switch lock;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_attendance);
myDb = new DatabaseHelper(this);
fname = findViewById(R.id.txtFullname);
eventname = findViewById(R.id.eventname);
faciname = findViewById(R.id.faciname);
attendance = findViewById(R.id.btnatt);
view = findViewById(R.id.btnview);
lock = findViewById(R.id.switchLock);
viewAll();
AddData();
lock.setOnCheckedChangeListener(this);
}
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (lock.isChecked()){
eventname.setEnabled(false);
faciname.setEnabled(false);
}else{
eventname.setEnabled(true);
faciname.setEnabled(true);
}
}
public void viewAll() {
view.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v) {
Cursor res = myDb.getAllData();
if (res.getCount() == 0) {
// show message
showMessage("Error", "Nothing found");
return;
}
StringBuffer buffer = new StringBuffer();
while (res.moveToNext()) {
buffer.append("ID :" + res.getString(0) + "\n");
buffer.append("NAME :" + res.getString(1) + "\n");
buffer.append("EVENT :" + res.getString(2) + "\n");
buffer.append("FACILITATOR :" + res.getString(3) + "\n"+"\n");
}
// Show all data
showMessage("ATTENDANCE LIST", buffer.toString());
}
}
);
}
public void showMessage(String title, String Message) {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setCancelable(true);
builder.setTitle(title);
builder.setMessage(Message);
builder.show();
}
public void AddData() {
attendance.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
final String valInput = fname.getText().toString();
final String valInput1 = eventname.getText().toString();
final String valInput2 = faciname.getText().toString();
boolean valid = true;
if (TextUtils.isEmpty(valInput)) {
fname.setError("This Item must not be empty!");
valid = false;
}
if (TextUtils.isEmpty(valInput1)) {
eventname.setError("This Item must not be empty!");
valid = false;
}
if (TextUtils.isEmpty(valInput2)) {
faciname.setError("This Item must not be empty!");
valid = false;
}
if (valid) {
boolean isExist = myDb.checkIfRecordExist(DatabaseHelper.TABLE_NAME, DatabaseHelper.COL_1, fname.getText().toString());
if (!isExist) {
boolean isInserted = myDb.insertData(fname.getText().toString(), eventname.getText().toString(), faciname.getText().toString());
if (isInserted) {
Toast.makeText(Attendance.this, "Attendance Success", Toast.LENGTH_LONG).show();
fname.setText(null);
} else if (isInserted == false) {
Toast.makeText(Attendance.this, "Failed to Attendance", Toast.LENGTH_LONG).show();
}
}else if (isExist == true){
Toast.makeText(Attendance.this, "Failed to Attendance "+fname+" Already Existed", Toast.LENGTH_LONG).show();
}
}
}
}); }
public boolean onKeyDown(int keyCode, KeyEvent event) {
//Handle the back button
if (keyCode == KeyEvent.KEYCODE_BACK) {
//Ask the user if they want to quit
new AlertDialog.Builder(this)
.setIcon(android.R.drawable.ic_dialog_alert)
.setTitle(R.string.Logout)
.setMessage(R.string.really_logout)
.setPositiveButton(R.string.yes, new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
//Stop the activity
Intent intent = new Intent(Attendance.this, MainActivity.class);
startActivity(intent);
Attendance.this.finish();
}
})
.setNegativeButton(R.string.no, null)
.show();
return true;
} else {
return super.onKeyDown(keyCode, event);
}
}}

change checkIfRecordExist method like this
public boolean checkIfRecordExist(String nameOfTable,String columnName1,String columnValue1,String columnName2,String columnValue2) {
SQLiteDatabase db = null;
try {
db = this.getReadableDatabase();
Cursor cursor = db.rawQuery("SELECT * FROM "+nameOfTable+" WHERE "+columnName1+"='"+columnValue1+"' and "+ columnName2 +"='"+columnValue2+"'",null);
.......................
change below line like this
boolean isExist = myDb.checkIfRecordExist(DatabaseHelper.TABLE_NAME, DatabaseHelper.COL_1, fname.getText().toString(),DatabaseHelper.COL_2, eventname.getText().toString())

SQLITE DATABASE error in displaying data to listview

im getting problem in displaying my data from sqlite db
my apps stops working when run and display no errors.
please help me
DatabaseHelper.java
public class DatabaseHelper extends SQLiteOpenHelper {
public static final String DATABASE_NAME = "ExpDatee.db";
public static final String TABLE_NAME = "EXPDATE_TABLE";
public static final String COL_1 = "PRO_ID";
public static final String COL_2 = "PRO_NAME";
public static final String COL_3 = "PRO_EXPDATE";
public static final String COL_4 = "PRO_DAYTILLEXP";
/**
private static final String SQL_CREATE_TABLE_EXPDATE = "CREATE TABLE " + TABLE_NAME + "("
+ PRO_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
+ PRO_NAME + " TEXT NOT NULL, "
+ PRO_EXPDATE+ " TEXT NOT NULL, "
+ PRO_DAYTILLEXP + " TEXT NOT NULL, "
+ ");";
**/
public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, 1);
// SQLiteDatabase db = this.getWritableDatabase();
}
#Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("CREATE TABLE " + TABLE_NAME + "(PRO_ID INTEGER PRIMARY KEY AUTOINCREMENT, " +
"PRO_NAME TEXT, " +
"PRO_EXPDATE TEXT," +
" PRO_DAYTILLEXP TEXT )");
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS "+TABLE_NAME);
onCreate(db);
}
//method to insert data
public boolean insertData(String PRO_NAME, String PRO_EXPDATE, String PRO_DAYTILLEXP)
{
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put(COL_2,PRO_NAME);
contentValues.put(COL_3,PRO_EXPDATE);
contentValues.put(COL_4,PRO_DAYTILLEXP);
Log.d(TAG, "ADD DATA : ADDING " + PRO_NAME + " TO " + TABLE_NAME);
Log.d(TAG, "ADD DATA : ADDING " + PRO_EXPDATE + " TO " + TABLE_NAME);
Log.d(TAG, "ADD DATA : ADDING " + PRO_DAYTILLEXP + " TO " + TABLE_NAME);
long result = db.insert(TABLE_NAME,null ,contentValues );
if (result == -1)
return false;
else
return true;
}
//get all data
public Cursor getData()
{
SQLiteDatabase db = this.getWritableDatabase();
String query = "SELECT * FROM" + TABLE_NAME;
Cursor data = db.rawQuery(query, null);
return data;
}
}
MainActivity.java
public class MainActivity extends AppCompatActivity {
DatabaseHelper myDB;
EditText etProductName, etDaysBeforeExp, etExpDate;
Button btnAddItem, btnViewItem;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myDB = new DatabaseHelper(this);
etProductName = (EditText)findViewById(R.id.etProductName);
etDaysBeforeExp = (EditText)findViewById(R.id.etDaysBeforeExp);
etExpDate = (EditText)findViewById(R.id.etExpDate);
btnAddItem = (Button)findViewById(R.id.btnAddItem);
btnViewItem = (Button)findViewById(R.id.btnViewItem);
btnAddItem.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String PRO_NAME = etProductName.getText().toString();
String PRO_EXPDATE = etExpDate.getText().toString();
String PRO_DAYTILLEXP = etDaysBeforeExp.getText().toString();
if(etProductName.length() !=0)
{
AddData(PRO_NAME,PRO_EXPDATE,PRO_DAYTILLEXP);
etProductName.setText("");
etExpDate.setText("");
etDaysBeforeExp.setText("");
}
else
{
toastMessage("PLEASE INSERT VALUE");
}
}
});
btnViewItem.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, ListDataActivity.class);
startActivity(intent);
}
});
}
public void AddData(String PRO_NAME, String PRO_EXPDATE, String PRO_DAYTILLEXP)
{
boolean InsertData = myDB.insertData(PRO_NAME,PRO_EXPDATE,PRO_DAYTILLEXP);
if(InsertData)
{
toastMessage("DATA INSERTED");
}
else
{
toastMessage("DATA NOT INSERTED");
}
}
private void toastMessage(String message) {
Toast.makeText(this,message, Toast.LENGTH_LONG).show();
}
}
ListDataActivity.java
public class ListDataActivity extends AppCompatActivity {
DatabaseHelper myDB;
private ListView mListView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_list_data);
populateListView();
}
private void populateListView() {
Cursor data = myDB.getData();
ArrayList<String> listData = new ArrayList<>();
while (data.moveToNext())
{
listData.add(data.getString(1));
listData.add(data.getString(2));
listData.add(data.getString(3));
}
ListAdapter adapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, listData);
mListView.setAdapter(adapter);
}
private void toastMessage(String message) {
Toast.makeText(this,message, Toast.LENGTH_LONG).show();
}
}

Initialized Listdataactivity
myDB = new DatabaseHelper(this);
Use Arrayadapter
ArrayAdapter<String> itemsAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, listData);
mListView.setAdapter(adapter);

Connecting to a SQLite database

I have already created a SQLite database for my BMI application in a new project.
Right now the problem is that I don't know how to connect to the database.
Is the private string file = "mydata"; to be changed to something else or is it correct?
CalculatorActivity. java
public class CalculatorActivity extends AppCompatActivity {
private EditText etWeight, etHeight;
private TextView tvDisplayResult, tvResultStatus;
Button bSave, bRead;
TextView tvStored;
String data;
private String file = "mydata";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_calculator);
etWeight = (EditText) findViewById(R.id.weight);
etHeight = (EditText) findViewById(R.id.height);
tvDisplayResult = (TextView) findViewById(R.id.display_result);
tvResultStatus = (TextView) findViewById(R.id.result_status);
tvResultStatus = (TextView) findViewById(R.id.result_status);
bSave = (Button) findViewById(R.id.savebutton);
bRead = (Button) findViewById(R.id.readbutton);
tvStored = (TextView) findViewById(R.id.displaysaveditem);
bSave.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
data = tvDisplayResult.getText().toString() + "\n";
try {
FileOutputStream fOut = openFileOutput(file, Context.MODE_APPEND);
fOut.write(data.getBytes());
fOut.close();
Toast.makeText(getBaseContext(), "file saved", Toast.LENGTH_SHORT).show();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
});
//Read
bRead.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
startActivity(new Intent(CalculatorActivity.this, RecordActivity.class));
finish();
}
});
}
public void onClick(View v) {
switch (v.getId()) {
case R.id.button_calculate:
Log.d("check", "Button Clicked!");
calculate();
break;
case R.id.button_reset:
reset();
break;
}
}
private void calculate() {
String weight = etWeight.getText().toString();
String height = etHeight.getText().toString();
double bmiResult = Double.parseDouble(weight) / (Double.parseDouble(height) * Double.parseDouble(height));
tvDisplayResult.setText(String.valueOf(bmiResult));
if (bmiResult < 18.5) {
tvResultStatus.setText(R.string.under);
tvResultStatus.setBackgroundColor(Color.parseColor("#F1C40F"));
tvResultStatus.setTextColor(Color.parseColor("#FFFFFF"));
} else if (bmiResult >= 18.5 && bmiResult <= 24.9) {
tvResultStatus.setText(R.string.normal);
tvResultStatus.setBackgroundColor(Color.parseColor("#2ECC71"));
tvResultStatus.setTextColor(Color.parseColor("#FFFFFF"));
} else if (bmiResult >= 24.9 && bmiResult <= 29.9) {
tvResultStatus.setText(R.string.over);
tvResultStatus.setBackgroundColor(Color.parseColor("#E57E22"));
tvResultStatus.setTextColor(Color.parseColor("#FFFFFF"));
} else if (bmiResult >= 30) {
tvResultStatus.setText(R.string.obes);
tvResultStatus.setBackgroundColor(Color.parseColor("#C0392B"));
tvResultStatus.setTextColor(Color.parseColor("#FFFFFF"));
}
}
private void reset() {
etWeight.setText("");
etHeight.setText("");
tvDisplayResult.setText(R.string.default_result);
tvResultStatus.setText(R.string.na);
tvResultStatus.setBackgroundColor(0);
tvResultStatus.setTextColor(0);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.menu_options, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle item selection
switch (item.getItemId()) {
case R.id.menu_home:
startActivity(new Intent(CalculatorActivity.this, CalculatorActivity.class));
finish();
break;
case R.id.menu_info:
startActivity(new Intent(CalculatorActivity.this, InformationActivity.class));
finish();
break;
}
return true;
}
}
DBHandler. java
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import java.util.ArrayList;
import java.util.List;
public class DBHandler extends SQLiteOpenHelper {
// Database Version
public static final int DATABASE_VERSION = 1;
// Database Name
public static final String DATABASE_NAME = "RecordDB";
// Record table name
public static final String TABLE_RECORD = "recordtable";
// Record Table Columns names
public static final String KEY_ID = "id";
public static final String KEY_BMI = "bmi";
public DBHandler(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db) {
String CREATE_RECORD_TABLE = "CREATE TABLE " + TABLE_RECORD + "(" + KEY_ID + " INTEGER PRIMARY KEY," + KEY_BMI + " TEXT " + ")";
db.execSQL(CREATE_RECORD_TABLE);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// Drop older table if existed
db.execSQL("DROP TABLE IF EXISTS " + TABLE_RECORD);
// Creating tables again
onCreate(db);
}
public void addBmi(Record record) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_BMI, record.getBmi()); // BMI value
// Inserting Row
db.insert(TABLE_RECORD, null, values);
db.close(); // Closing database connection
}
public List<Record> getAllRecords() {
List<Record> recordList = new ArrayList<Record>();
// Select All Query
String selectQuery = "SELECT * FROM " + TABLE_RECORD;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
Record record = new Record();
record.setId(Integer.parseInt(cursor.getString(0)));
record.setBmi(cursor.getString(1));
// Adding record to list
recordList.add(record);
} while (cursor.moveToNext());
}
// return record list
return recordList;
}
}

I don't know how to connect the database in my BMI application
Well, you need to declare it and initialize it.
public class CalculatorActivity extends AppCompatActivity {
private DBHandler dbHandler;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_calculator);
dbHandler = new DBHandler(this);
// Use it...
Is the private string file = "mydata"; need to be change to something else or its correct?
You are able to keep it, and it is correct, but it is not related to the database.

Android SQL query nullpointer can't get the data from database

here is the LogCat
I can't post image so i put it in google drive
link here
////////And here is the DB///////
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;
public class UserDB {
public static final String TABLE_USER = "User";
public static final String ID = "ID";
public static final String USERNAME = "USERNAME";
public static final String PASSWORD = "PASSWORD";
public static final String CHKPASSWORD = "CHKPASSWORD";
public static final String SEX = "SEX";
public static final String eat = "eat";
public static final String drink = "drink";
public static final String smoke = "smoke";
public static final String conctrolweigh = "conctrolweigh";
public static final String blosuger = "blosuger";
public static final String hospital = "hospital";
private Context Context = null;
public static final String Education = "Education";
public static class DatabaseHelper extends SQLiteOpenHelper{
public static final String DATABASE_NAME = "diabetes.db";
private static final int DATABASE_VERSION = 1;
//usertable
public DatabaseHelper(Context context, CursorFactory factory) {
super(context, DATABASE_NAME, factory, DATABASE_VERSION);
}
public static final String TABLE_USER_CREATE =
"CREATE TABLE " + TABLE_USER
+ "("
+ ID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
+ USERNAME + " text , "
+ PASSWORD+ " text ,"
+ CHKPASSWORD+ " text ,"
+ SEX+ " text ,"
+ eat + " text , "
+ drink + " text, "
+ smoke + " text, "
+ conctrolweigh + " text, "
+ blosuger + " text, "
+ hospital + " text, "
+ Education + " text);";
public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, 1);
}
#Override
public void onOpen(SQLiteDatabase db) {
super.onOpen(db);
// 每次成功打開資料庫後首先被執行
}
#Override
public synchronized void close() {
super.close();
}
#Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(TABLE_USER_CREATE);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROPB TABLE IF EXISTS " + TABLE_USER);
onCreate(db);
}
}
public DatabaseHelper dbHelper;
public SQLiteDatabase db;
public UserDB(Context context){
this.Context = context;
DatabaseHelper openHelper = new DatabaseHelper(this.Context);
this.db = openHelper.getWritableDatabase();
}
public UserDB open() throws SQLException{
dbHelper = new DatabaseHelper(Context);
db = dbHelper.getWritableDatabase();
return this;
}
public void close(){
dbHelper.close();
}
//add user
public void insertEntry(String ID, String PWD,String CHPW,String SEX,String eat,String drink,String smoke,String conctrolweigh,String blosuger,String hospital,String Education){
if (PWD.equals(CHPW)){
ContentValues newValues = new ContentValues();
newValues.put("USERNAME", ID);
newValues.put("PASSWORD", PWD);
newValues.put("CHKPASSWORD", CHPW);
newValues.put("SEX", SEX);
newValues.put("eat", eat);
newValues.put("drink", drink);
newValues.put("smoke", smoke);
newValues.put("conctrolweigh", conctrolweigh);
newValues.put("blosuger", blosuger);
newValues.put("hospital", hospital);
newValues.put("Education", Education);
db.insert(TABLE_USER, null, newValues);
}else{
}
}
public String getSinlgeEntry(String userName) {
Cursor cursor = db.query("User", null, " USERNAME=?",
new String[] { userName }, null, null, null);
if (cursor.getCount() < 1) // UserName Not Exist
return "Not Exist";
cursor.moveToFirst();
String password = cursor.getString(cursor.getColumnIndex("PASSWORD"));
return password;
}
public SQLiteDatabase getReadableDatabase() {
// TODO Auto-generated method stub
return null;
}
}
//////here is the Activity//////////
public class SelfteachingActivity extends Activity {
Button btnselback,tvartical ,tvfood,tvhealth,tvexcise;
TextView tvid,tvstore,tveat,tvhospital,tvblosuger,tvconctrolweigh,tvdrink,tvsmoke,tvSEX,tvEducation;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_selfteaching);
findViews();
setListeners();
//openDatabase();
String username= (this.getIntent().getExtras().getString("username"));
tvstore.setText(username);
tvid.setText(tvstore.getText().toString());
query();
}
private void query() {
UserDB helper = new UserDB(this);
SQLiteDatabase db = helper.getReadableDatabase();
helper.open();
if(helper.getReadableDatabase() == null){
Log.i("Log Activity Test", "helper is null!!!!!!!!!");
}
String user = tvstore.getText().toString();
try {
Log.i("Log Activity Test", "start db!!");
Cursor cursor = db.rawQuery("SELECT SEX,hospital,blosuger,drink,conctrolweigh,smoke,Education,eat FROM User Where USERNAME ='"+user+"'", null);
if(cursor!=null){
int rows_num = cursor.getCount();
cursor.moveToFirst();
while (!cursor.isAfterLast()) {
Integer Id = cursor.getInt(cursor.getColumnIndex("id"));
tvSEX.setText(cursor.getString(cursor.getColumnIndex("SEX")));
tvhospital.setText(cursor.getString(cursor.getColumnIndex("hospital")));
tvblosuger.setText(cursor.getString(cursor.getColumnIndex("blosuger")));
tvdrink.setText(cursor.getString(cursor.getColumnIndex("drink")));
tvconctrolweigh.setText(cursor.getString(cursor.getColumnIndex("conctrolweigh")));
tvsmoke.setText(cursor.getString(cursor.getColumnIndex("smoke")));
tvEducation.setText(cursor.getString(cursor.getColumnIndex("Education")));
tveat.setText(cursor.getString(cursor.getColumnIndex("eat")));
cursor.moveToNext();
}
}
} catch (Exception ex) {
ex.printStackTrace();
} finally {
}
}
private long exitTime = 0;
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if(keyCode == KeyEvent.KEYCODE_BACK && event.getAction() == KeyEvent.ACTION_DOWN){
if((System.currentTimeMillis()-exitTime) > 2000){
Toast.makeText(getApplicationContext(), "再按一次返回鍵退出", Toast.LENGTH_SHORT).show();
exitTime = System.currentTimeMillis();
} else {
finish();
System.exit(0);
}
return true;
}
return super.onKeyDown(keyCode, event);
}
private void findViews(){
btnselback = (Button)findViewById(R.id.buttonselback);
tvartical = (Button)findViewById(R.id.buttonartical);
tvfood = (Button)findViewById(R.id.buttonfood);
tvhealth = (Button)findViewById(R.id.buttonhealth);
tvexcise = (Button)findViewById(R.id.buttonescise);
tvid = (TextView)findViewById(R.id.tVsid);
tvstore = (TextView)findViewById(R.id.tvstore);
tveat = (TextView)findViewById(R.id.tveat);
tvhospital= (TextView)findViewById(R.id.tvhospital);
tvblosuger= (TextView)findViewById(R.id.tvblosuger);
tvconctrolweigh= (TextView)findViewById(R.id.tvconctrolweigh);
tvdrink= (TextView)findViewById(R.id.tvdrink);
tvsmoke= (TextView)findViewById(R.id.tvsmoke);
tvSEX= (TextView)findViewById(R.id.tvSEX);
tvEducation= (TextView)findViewById(R.id.tvEducation);
}
private void setListeners(){
//回上一頁
btnselback.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
String username = tvstore.getText().toString();
Intent intent = new Intent();
intent.setClass(SelfteachingActivity.this, LoginActivity.class);
intent.putExtra("username", username );
startActivity(intent);
SelfteachingActivity.this.finish();
}
});
//衛教文章
tvartical.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View arg0) {
String username = tvstore.getText().toString();
Intent intent = new Intent();
intent.setClass(SelfteachingActivity.this, ArticalActivity.class);
intent.putExtra("SEX", tvSEX.getText().toString() );
intent.putExtra("username", username );
intent.putExtra("hospital", tvhospital.getText().toString());
intent.putExtra("blosuger", tvblosuger.getText().toString() );
intent.putExtra("drink", tvdrink.getText().toString() );
intent.putExtra("conctrolweigh", tvconctrolweigh.getText().toString());
intent.putExtra("smoke", tvsmoke.getText().toString());
intent.putExtra("Education", tvEducation.getText().toString());
intent.putExtra("eat", tveat.getText().toString());
startActivity(intent);
SelfteachingActivity.this.finish();
}
});
//食物衛教
tvfood.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
String username = tvstore.getText().toString();
Intent intent = new Intent();
intent.setClass(SelfteachingActivity.this, FoodActivity.class);
intent.putExtra("username", username );
intent.putExtra("SEX", tvSEX.getText().toString() );
intent.putExtra("hospital", tvhospital.getText().toString());
intent.putExtra("blosuger", tvblosuger.getText().toString() );
intent.putExtra("drink", tvdrink.getText().toString() );
intent.putExtra("conctrolweigh", tvconctrolweigh.getText().toString());
intent.putExtra("smoke", tvsmoke.getText().toString());
intent.putExtra("Education", tvEducation.getText().toString());
intent.putExtra("eat", tveat.getText().toString());
startActivity(intent);
SelfteachingActivity.this.finish();
}
});
//健康衛教
tvhealth.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
String username = tvstore.getText().toString();
Intent intent = new Intent();
intent.setClass(SelfteachingActivity.this, HealthActivity.class);
intent.putExtra("username", username );
intent.putExtra("SEX", tvSEX.getText().toString() );
intent.putExtra("hospital", tvhospital.getText().toString());
intent.putExtra("blosuger", tvblosuger.getText().toString() );
intent.putExtra("drink", tvdrink.getText().toString() );
intent.putExtra("conctrolweigh", tvconctrolweigh.getText().toString());
intent.putExtra("smoke", tvsmoke.getText().toString());
intent.putExtra("Education", tvEducation.getText().toString());
intent.putExtra("eat", tveat.getText().toString());
startActivity(intent);
SelfteachingActivity.this.finish();
}
});
//運動衛教
tvexcise.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
String username = tvstore.getText().toString();
Intent intent = new Intent();
intent.setClass(SelfteachingActivity.this, ExciseActivity.class);
intent.putExtra("username", username );
intent.putExtra("SEX", tvSEX.getText().toString() );
intent.putExtra("hospital", tvhospital.getText().toString());
intent.putExtra("blosuger", tvblosuger.getText().toString() );
intent.putExtra("drink", tvdrink.getText().toString() );
intent.putExtra("conctrolweigh", tvconctrolweigh.getText().toString());
intent.putExtra("smoke", tvsmoke.getText().toString());
intent.putExtra("Education", tvEducation.getText().toString());
intent.putExtra("eat", tveat.getText().toString());
startActivity(intent);
SelfteachingActivity.this.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.selfteaching, menu);
return true;
}
}
Problem:
1.i don't get any data from SQL but no crash
what is the problem with my code?
the program stop in here
Cursor cursor = db.rawQuery("SELECT SEX,hospital,blosuger,drink,conctrolweigh,smoke,Education,eat FROM User Where USERNAME ='"+user+"'", null);
and say null pointer , i check the db and is null , i don't know how this happen.
plz help me

Method that you call
SQLiteDatabase db = helper.getReadableDatabase();
returns your null due to your code:
public SQLiteDatabase getReadableDatabase() {
// TODO Auto-generated method stub
return null;
}

Develop Reference

Java is a programming language and computing platform first released by Sun Microsystems in 1995.

How to insert and retrieve data display button using sqlite - java

Related

SQL Lite Data not being inserted (Android Studio in java)

Android Studio + Database - Multiple check data to insert data if not exists

SQLITE DATABASE error in displaying data to listview

Connecting to a SQLite database

Android SQL query nullpointer can't get the data from database

Categories

Resources