I create an application for calculate university grades and I want to add an option to sort the database.
My database is based on sqlite and every time that I need to show the list of all the courses that were added by the user, I take them one by one and add the list Data Adaptar. It always shows the course by insert order, and I want now to give an option for change the list order to By name of course/By year and more..
I attached the code of the activity, DataListActivity:
package com.example.ido.grades;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.ContextMenu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Spinner;
import android.widget.Toast;
import java.util.Collections;
public class DataListActivity extends ActionBarActivity {
ListView listView;
SQLiteDatabase sqLiteDatabase;
CourseDbHelper courseDbHelper;
Cursor cursor;
ListDataAdaptar listDataAdaptar;
Spinner sortSpinner;
ArrayAdapter<String> sortAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.update_course);
hideActionBar();
sortSpinner = (Spinner)findViewById(R.id.sortSpinner);
String[] sortItems = new String[]{"Sort by","Course name","Year","Semester", "Grade", "Points"};
sortAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, sortItems);
sortSpinner.setAdapter(sortAdapter);
listView = (ListView) findViewById(R.id.list_view);
listDataAdaptar = new ListDataAdaptar(getApplicationContext(),R.layout.row_layout);
listView.setAdapter(listDataAdaptar);
registerForContextMenu(listView);
courseDbHelper = new CourseDbHelper(getApplicationContext());
sqLiteDatabase = courseDbHelper.getReadableDatabase();
cursor = courseDbHelper.getInformation(sqLiteDatabase);
registerForContextMenu(listView);
View header = getLayoutInflater().inflate(R.layout.header, null);
listView.addHeaderView(header);
if (!cursor.moveToFirst()){
}
else {
do {
String year,semester,course,points,grade;
year = cursor.getString(0);
semester = cursor.getString(1);
course = cursor.getString(2);
points = cursor.getString(3);
grade = cursor.getString(4);
DataProvider dataProvider = new DataProvider(year,semester,course,points,grade);
listDataAdaptar.add(dataProvider);
}
while (cursor.moveToNext());
}
}
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {
MenuInflater inflater = getMenuInflater();
if (((AdapterView.AdapterContextMenuInfo)menuInfo).position == 0) {
return;
}
inflater.inflate(R.menu.menu_data_list, menu);
}
public boolean onContextItemSelected(MenuItem item) {
AdapterView.AdapterContextMenuInfo info =
(AdapterView.AdapterContextMenuInfo) item.getMenuInfo();
final int mySelectedRowIndex = info.position-1;
switch (item.getItemId()) {
case R.id.update_item:
courseDbHelper = new CourseDbHelper(getApplicationContext());
sqLiteDatabase = courseDbHelper.getReadableDatabase();
DataProvider raw2 = (DataProvider) listDataAdaptar.getItem(mySelectedRowIndex);
Intent i = new Intent(DataListActivity.this, UpdateCourseActivity.class);
String year = raw2.getYear();
String semester = raw2.getSemester();
String course = raw2.getCourse();
String points = raw2.getPoints();
String grade = raw2.getGrade();
int semIndex;
if (semester.equals("A'")) {
semIndex = 1;
} else if (semester.equals("B'")) {
semIndex = 2;
} else {
semIndex = 3;
}
i.putExtra("YEAR", year);
i.putExtra("SEMESTER", Integer.toString(semIndex));
i.putExtra("COURSE", course);
i.putExtra("POINTS", points);
i.putExtra("GRADE", grade);
i.putExtra("POS", Integer.toString(mySelectedRowIndex));
startActivity(i);
return true;
case R.id.delete_item:
AlertDialog.Builder builder1 = new AlertDialog.Builder(this);
DataProvider raw3 = (DataProvider) listDataAdaptar.getItem(mySelectedRowIndex);
builder1.setMessage("The course '" + raw3.getCourse() + "' Will delete, Are you sure?");
builder1.setCancelable(true);
builder1.setPositiveButton("Yes",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
delete(mySelectedRowIndex);
dialog.cancel();
}
});
builder1.setNegativeButton("No",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
dialog.cancel();
}
});
AlertDialog alert11 = builder1.create();
alert11.show();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
public void onBackPressed() {
startActivity(new Intent(this, MainActivity.class));
}
public void delete(int mySelectedRowIndex){
courseDbHelper = new CourseDbHelper(getApplicationContext());
sqLiteDatabase = courseDbHelper.getReadableDatabase();
DataProvider raw = (DataProvider)listDataAdaptar.getItem(mySelectedRowIndex);
courseDbHelper.deleteInformation(raw.getYear(), raw.getSemester(), raw.getCourse(), raw.getPoints(), raw.getGrade());
Toast.makeText(this, "The course succesfully deleted", Toast.LENGTH_SHORT).show();
finish();
startActivity(getIntent());
}
private void hideActionBar() {
//Hide the action bar only if it exists
if (getSupportActionBar() != null) {
getSupportActionBar().hide();
}
}
}
CourseDBHelper.java:
package com.example.ido.grades;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class CourseDbHelper extends SQLiteOpenHelper {
private static final String DATABASE_NAME = "COURSEINFO.DB";
private static final int DATABASE_VERSION = 1;
public String CREATE_QUERY = "CREATE TABLE " + UserCourse.NewCourseInfo.TABLE_NAME + "("+ UserCourse.NewCourseInfo.YEAR+" TEXT,"
+ UserCourse.NewCourseInfo.SEMESTER+" TEXT,"+ UserCourse.NewCourseInfo.COURSE+" TEXT,"+ UserCourse.NewCourseInfo.POINTS+" TEXT,"
+ UserCourse.NewCourseInfo.GRADE+" TEXT);";
public CourseDbHelper (Context context){
super(context, DATABASE_NAME, null, DATABASE_VERSION);
Log.e("DATABASE_OPERATIONS","Database created/opened...");
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(CREATE_QUERY);
Log.e("DATABASE_OPERATIONS", "Table created");
}
public void putInformation(String year, String semester, String course, String points,String grade,SQLiteDatabase db){
ContentValues cv = new ContentValues();
cv.put(UserCourse.NewCourseInfo.YEAR, year);
cv.put(UserCourse.NewCourseInfo.SEMESTER, semester);
cv.put(UserCourse.NewCourseInfo.COURSE, course);
cv.put(UserCourse.NewCourseInfo.POINTS,points);
cv.put(UserCourse.NewCourseInfo.GRADE, grade);
db.insert(UserCourse.NewCourseInfo.TABLE_NAME, null, cv);
Log.e("DATABASE_OPERATIONS", "One raw inserted");
}
public double updateInformation(String old_course,String year, String semester, String course, String points,String grade,SQLiteDatabase db){
ContentValues cv = new ContentValues();
cv.put(UserCourse.NewCourseInfo.YEAR, year);
cv.put(UserCourse.NewCourseInfo.SEMESTER, semester);
cv.put(UserCourse.NewCourseInfo.COURSE, course);
cv.put(UserCourse.NewCourseInfo.POINTS,points);
cv.put(UserCourse.NewCourseInfo.GRADE, grade);
String Selection = UserCourse.NewCourseInfo.COURSE + " LIKE ?";
String[] Selection_args = {old_course};
double count = db.update(UserCourse.NewCourseInfo.TABLE_NAME,cv,Selection,Selection_args);
return count;
}
public Cursor getInformation(SQLiteDatabase db){
Cursor cursor;
String[] projections = {UserCourse.NewCourseInfo.YEAR,UserCourse.NewCourseInfo.SEMESTER,
UserCourse.NewCourseInfo.COURSE, UserCourse.NewCourseInfo.POINTS,UserCourse.NewCourseInfo.GRADE};
cursor= db.query(UserCourse.NewCourseInfo.TABLE_NAME,projections,null,null,null,null,null );
return cursor;
}
public void deleteInformation(String year, String semester,
String course,String points, String grade){
SQLiteDatabase db = null;
try
{
db = this.getWritableDatabase();
String where = UserCourse.NewCourseInfo.YEAR + " = ? AND "
+ UserCourse.NewCourseInfo.SEMESTER + " = ? AND "
+ UserCourse.NewCourseInfo.COURSE + " = ? AND "
+ UserCourse.NewCourseInfo.POINTS + " = ? AND "
+ UserCourse.NewCourseInfo.GRADE + " = ?";
double iNumberDeleted = db.delete(
UserCourse.NewCourseInfo.TABLE_NAME,
where,
new String[]{year, semester, course, points, grade}
);
// you might want to evaluate the number of affected rows
}
catch (Exception ex)
{
Log.d("DB_DELETE", "...your data..." + "\n" + ex.getMessage());
}
finally
{
if (db != null)
db.close();
}
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
}
DataProvider.java:
package com.example.ido.grades;
/**
* Created by Ido on 08/08/2015.
*/
public class DataProvider {
private String year;
private String semester;
public String getYear() {
return year;
}
public void setYear(String year) {
this.year = year;
}
public String getSemester() {
return semester;
}
public void setSemester(String semester) {
this.semester = semester;
}
public String getCourse() {
return course;
}
public void setCourse(String course) {
this.course = course;
}
public String getPoints() {
return points;
}
public void setPoints(String points) {
this.points = points;
}
public String getGrade() {
return grade;
}
public void setGrade(String grade) {
this.grade = grade;
}
private String course;
private String points;
private String grade;
public DataProvider(String year, String semester,String course, String points, String grade){
this.year=year;
this.semester=semester;
this.course=course;
this.points=points;
this.grade=grade;
}
}
I hope its enough to understand what i want. Thanks!
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