I created a simple android application which asks for the users details such as name, blood type and contact number and stores it in a database. I deleted the database using the following code:
/*Table was deleted*/
public void deleteProducts(){
SQLiteDatabase db = getWritableDatabase();
db.execSQL("DROP TABLE "+TABLE_PRODUCTS);
}
However when I now try and create a database I am getting an error.
Database Class
package com.example.androidsimpledbapp1;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.Cursor;
import android.content.Context;
import android.content.ContentValues;
public class MyDBHandler extends SQLiteOpenHelper {
/*
* Class for Working with DB
*/
//Update each time DB structure changes e.g. adding new property
private static final int DATABASE_VERSION =1;
//DB Name
private static final String DATABASE_NAME = "deets.db";
//Table name
public static final String TABLE_PRODUCTS = "products";
//DB Columns
public static final String COLUMN_ID = "_Id";
public static final String COLUMN_PERSONNAME = "firstName";
public static final String COLUMN_PERSONBLOOD = "bloodType";
public static final String COLUMN_PERSONCONTACT = "contactName";
public static final String COLUMN_PERSONNUMBER = "phoneNumber";
public static final String COLUMN_PERSONRELATION = "relationship";
//Constructor
/*
* Passing information to super class in SQL
* Context is background information
* name of db
* Database version
*/
public MyDBHandler(Context context, String name, SQLiteDatabase.CursorFactory factory, int version){
super(context, DATABASE_NAME, factory, DATABASE_VERSION);
}
/*
* What to do first time when you create DB
* Creates the table the very first time
* (non-Javadoc)
* @see android.database.sqlite.SQLiteOpenHelper#onCreate(android.database.sqlite.SQLiteDatabase)
* Remember to use Commas as shown below
*/
@Override
public void onCreate(SQLiteDatabase db){
String query = "CREATE TABLE "+ TABLE_PRODUCTS + "(" +
COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, "+
COLUMN_PERSONNAME + " TEXT, "+
COLUMN_PERSONBLOOD + " TEXT, "+
COLUMN_PERSONCONTACT + " TEXT, "+
COLUMN_PERSONNUMBER + " TEXT, " +
COLUMN_PERSONRELATION + " TEXT " +
");";
//Execute the query
db.execSQL(query);
}
/*
* If ever upgrading DB call this method
* (non-Javadoc)
* @see android.database.sqlite.SQLiteOpenHelper#onUpgrade(android.database.sqlite.SQLiteDatabase, int, int)
*/
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion){
//Delete the current table
db.execSQL("DROP TABLE IF EXISTS" + TABLE_PRODUCTS);
//create new table
onCreate(db);
}
//Add new row to the database
public void addProduct(Details details){
//Built in class - set values for different columns
//Makes inserting rows quick and easy
ContentValues values = new ContentValues();
values.put(COLUMN_PERSONNAME, details.get_firstName());
values.put(COLUMN_PERSONBLOOD, details.get_bloodType());
values.put(COLUMN_PERSONCONTACT, details.get_contactName());
values.put(COLUMN_PERSONNUMBER, details.get_phoneNumber());
values.put(COLUMN_PERSONRELATION, details.get_relationship());
SQLiteDatabase db = getWritableDatabase();
db.insert(TABLE_PRODUCTS, null, values);
db.close();
}
/*Table was deleted*/
public void deleteProducts(){
SQLiteDatabase db = getWritableDatabase();
db.execSQL("DROP TABLE "+TABLE_PRODUCTS);
}
//Take DB and Convert to String
public String databaseToString(){
String dbString = "";
SQLiteDatabase db = getWritableDatabase();
//Every Column and row
String query = "SELECT * FROM " + TABLE_PRODUCTS + " WHERE 1";
//Cursor points to a location in your results
//First row point here, second row point here
Cursor c = db.rawQuery(query, null);
c.moveToFirst();
while(!c.isAfterLast()){
//Extracts first name and adds to string
if(c.getString(c.getColumnIndex("firstName"))!=null){
dbString += c.getString(c.getColumnIndex("firstName"));
c.moveToNext();
/*
* Displaying all other columns
*/
}
}
db.close();
return dbString;
}
}
Details Class
package com.example.androidsimpledbapp1;
public class Details {
//primary key
private int _id;
//Properties
private String _firstName;
private String _bloodType;
private String _contactName;
private String _phoneNumber;
private String _relationship;
//Dont Have to Enter Everything each time
public Details(){
}
public Details(String firstName){
this.set_firstName(firstName);
}
//Passing in details
//Setting values from the user
public Details(String firstName, String bloodType,
String contactName, String phoneNumber,
String relationship){
this.set_firstName(firstName);
this.set_bloodType(bloodType);
this.set_contactName(contactName);
this.set_phoneNumber(phoneNumber);
this.set_relationship(relationship);
}
//Retrieve the data
public int get_id() {
return _id;
}
//Setter allows to give property
public void set_id(int _id) {
this._id = _id;
}
public String get_firstName() {
return _firstName;
}
public void set_firstName(String _firstName) {
this._firstName = _firstName;
}
public String get_bloodType() {
return _bloodType;
}
public void set_bloodType(String _bloodType) {
this._bloodType = _bloodType;
}
public String get_contactName() {
return _contactName;
}
public void set_contactName(String _contactName) {
this._contactName = _contactName;
}
public String get_phoneNumber() {
return _phoneNumber;
}
public void set_phoneNumber(String _phoneNumber) {
this._phoneNumber = _phoneNumber;
}
public String get_relationship() {
return _relationship;
}
public void set_relationship(String _relationship) {
this._relationship = _relationship;
}
}
Edit Screen - Where the user enters the data and taps the save button which invokes the saveMe method
package com.example.androidsimpledbapp1;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
public class EditScreen extends Activity {
EditText firstNameInput;
EditText bloodTypeInput;
EditText contacNameInput;
EditText phoneNumberInput;
EditText relationshipInput;
TextView displayName;
MyDBHandler dbHandler;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_edit_screen);
//Setting EditTexts
firstNameInput = (EditText) findViewById(R.id.inputname);
bloodTypeInput = (EditText) findViewById(R.id.inputblood);
contacNameInput = (EditText) findViewById(R.id.inputcontact);
phoneNumberInput = (EditText) findViewById(R.id.inputnum);
relationshipInput = (EditText) findViewById(R.id.inputraltion);
displayName = (TextView) findViewById(R.id.fullname);
//Setting DbHandler object
dbHandler = new MyDBHandler(this, null, null, 1);
}
public void saveMe(View v){
/*
* Making a new object
* Object takes 5 parameters
*/
Details detail = new Details(firstNameInput.getText().toString(),
bloodTypeInput.getText().toString(),
contacNameInput.getText().toString(),
phoneNumberInput.getText().toString(),
relationshipInput.getText().toString());
dbHandler.addProduct(detail);
/*Sending Text To Main Activity*/
String dbString = dbHandler.databaseToString();
Intent myIntent = new Intent(v.getContext(),MainActivity.class);
myIntent.putExtra("mytext",dbString);
startActivity(myIntent);
/*End of Sending to Main Activity*/
}
public void clearBtnPressed(View v){
dbHandler.deleteProducts();
}
}
Log Cat Error
08-10 23:27:39.968: E/AndroidRuntime(356): FATAL EXCEPTION: main 08-10 23:27:39.968: E/AndroidRuntime(356): java.lang.IllegalStateException: Could not execute method of the activity 08-10 23:27:39.968: E/AndroidRuntime(356): at android.view.View$1.onClick(View.java:2144) 08-10 23:27:39.968: E/AndroidRuntime(356): at android.view.View.performClick(View.java:2485) 08-10 23:27:39.968: E/AndroidRuntime(356): at android.view.View$PerformClick.run(View.java:9080) 08-10 23:27:39.968: E/AndroidRuntime(356): at android.os.Handler.handleCallback(Handler.java:587) 08-10 23:27:39.968: E/AndroidRuntime(356): at android.os.Handler.dispatchMessage(Handler.java:92) 08-10 23:27:39.968: E/AndroidRuntime(356): at android.os.Looper.loop(Looper.java:130) 08-10 23:27:39.968: E/AndroidRuntime(356): at android.app.ActivityThread.main(ActivityThread.java:3683) 08-10 23:27:39.968: E/AndroidRuntime(356): at java.lang.reflect.Method.invokeNative(Native Method) 08-10 23:27:39.968: E/AndroidRuntime(356): at java.lang.reflect.Method.invoke(Method.java:507) 08-10 23:27:39.968: E/AndroidRuntime(356): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839) 08-10 23:27:39.968: E/AndroidRuntime(356): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597) 08-10 23:27:39.968: E/AndroidRuntime(356): at dalvik.system.NativeStart.main(Native Method) 08-10 23:27:39.968: E/AndroidRuntime(356): Caused by: java.lang.reflect.InvocationTargetException 08-10 23:27:39.968: E/AndroidRuntime(356): at java.lang.reflect.Method.invokeNative(Native Method) 08-10 23:27:39.968: E/AndroidRuntime(356): at java.lang.reflect.Method.invoke(Method.java:507) 08-10 23:27:39.968: E/AndroidRuntime(356): at android.view.View$1.onClick(View.java:2139) 08-10 23:27:39.968: E/AndroidRuntime(356): ... 11 more 08-10 23:27:39.968: E/AndroidRuntime(356): Caused by: android.database.sqlite.SQLiteException: no such table: products: , while compiling: SELECT * FROM products WHERE 1 08-10 23:27:39.968: E/AndroidRuntime(356): at android.database.sqlite.SQLiteCompiledSql.native_compile(Native Method) 08-10 23:27:39.968: E/AndroidRuntime(356): at android.database.sqlite.SQLiteCompiledSql.compile(SQLiteCompiledSql.java:92) 08-10 23:27:39.968: E/AndroidRuntime(356): at android.database.sqlite.SQLiteCompiledSql.(SQLiteCompiledSql.java:65) 08-10 23:27:39.968: E/AndroidRuntime(356): at android.database.sqlite.SQLiteProgram.(SQLiteProgram.java:83) 08-10 23:27:39.968: E/AndroidRuntime(356): at android.database.sqlite.SQLiteQuery.(SQLiteQuery.java:49) 08-10 23:27:39.968: E/AndroidRuntime(356): at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:42) 08-10 23:27:39.968: E/AndroidRuntime(356): at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1356) 08-10 23:27:39.968: E/AndroidRuntime(356): at android.database.sqlite.SQLiteDatabase.rawQuery(SQLiteDatabase.java:1324) 08-10 23:27:39.968: E/AndroidRuntime(356): at com.example.androidsimpledbapp1.MyDBHandler.databaseToString(MyDBHandler.java:107) 08-10 23:27:39.968: E/AndroidRuntime(356): at com.example.androidsimpledbapp1.EditScreen.saveMe(EditScreen.java:60) 08-10 23:27:39.968: E/AndroidRuntime(356): ... 14 more
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