Compare String with Bubble Sort Algorithm

Question

I have a program that will fetch several String from database (announcementId, and announcementTitle),

then for every string fetched from the database, I want to compare each of them (Compare all the fetched announcementId),

if the string (announcementId) has different value then it will create a new Button using the announcementTitle as it's(the button) value fetch from database.

I tried to learn how, and found out that bubble sort algorithm can be used in this case, but there is some error in the program.. Index out of bound exception.. Then I tried some code and tried to change the array, but it still didnt work.

Could you please take a look at my code and tell me where is the error and the best way to fix the error

This is my code :

    myDb = new Database(ViewAllAnnouncement.this);
    myDb.open();
    totalAnnouncement = myDb.countHowManyAnnouncement(username);
    String temp = Integer.toString(totalAnnouncement);
    //Toast.makeText(getApplicationContext(), temp, Toast.LENGTH_LONG).show();

    String[] announcementTitle = myDb.fetchMyAnnouncement(username);
    String[] announcementId = myDb.fetchAnnouncementId(username);

    for (int i = 0; i < totalAnnouncement; i++) {

        for (int j = 0; j < totalAnnouncement - i; j++) {
            if (j > 0 || j < totalAnnouncement-i) {
                if (!announcementId[j].equals(announcementId[i])) {

                    newBt = new Button(this);
                    newBt.setTag(announcementId[i]);
                    newBt.setText(announcementTitle[i]);
                    newBt.setOnClickListener(new View.OnClickListener() {

                        @Override
                        public void onClick(View v) {
                            // TODO Auto-generated method stub
                            Button mButt = (Button) v;
                            String temp = (String) mButt.getTag();
                            Intent intent = new Intent(
                                    "com.example.teamizer.VIEWCHILDANNOUNCEMENT");
                            intent.putExtra("annId", temp);
                            startActivity(intent);
                        }
                    });
                    layout.addView(newBt);
                }
            }
        }
    }

    myDb.close();

And this is my method to return the announcementId

    public String[] fetchAnnouncementId(String Username) {
    // TODO Auto-generated method stub
    int i = 0;

    String Query = "SELECT b." + ANNOUNCEMENT_ID + " FROM "
            + MS_GROUP_DETAIL + " a, " + MS_ANNOUNCEMENT_DETAIL + " b, "
            + MS_ANNOUNCEMENT + " c WHERE a." + GROUP_ID + " = b."
            + GROUP_ID + " AND b. " + ANNOUNCEMENT_ID + " = c."
            + ANNOUNCEMENT_ID + " AND a." + MEMBER_USERNAME + " =? ORDER BY b." +ANNOUNCEMENT_ID;
    Cursor c = ourDatabase.rawQuery(Query, new String[] { Username });

    String temp[] = new String[c.getCount()];
    int iArray = c.getColumnIndex(ANNOUNCEMENT_ID);

    c.moveToFirst();
    for (c.moveToFirst(); !c.isAfterLast(); c.moveToNext()) {
        temp[i] = c.getString(iArray);
        i++;
    }
    c.close();
    return temp;
}

Answer 1

If bubble sort is the answer you must have misunderstood the question. I strongly recommend you just add

ORDER BY announcementId

to the end of your query. That way the database will sort by your column for you.

Edit You could use

ORDER BY 1

to sort by the first column (and omit the name). And, then your code should look something like

for (int i = 0; i < totalAnnouncement - 1;) {
    int j = i + 1;
    for (; j < totalAnnouncement; j++) {
        if (!announcementId[j].equals(announcementId[i])) {
            break;
        }
    }
    // j is the first value where the announcementId changes
    newBt = new Button(this);
    newBt.setTag(announcementId[i]);
    newBt.setText(announcementTitle[i]);
    newBt.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Button mButt = (Button) v;
            String temp = (String) mButt.getTag();
            Intent intent = new Intent(
                    "com.example.teamizer.VIEWCHILDANNOUNCEMENT");
            intent.putExtra("annId", temp);
            startActivity(intent);
        }
    });
    layout.addView(newBt);
    i = j; // <-- assign j to i.
}