How to get all single column values then pass it to String[]?

Question

I got a big problem here. I create databasehelper class to handle all of my query function. Now I try to make a function that will load all values of a column from my database but I dont know how to do it. FYI I got 3 columns inside my database table. Here is my code so far:

(UPDATED, it works and gives me values now)

public List<Content> getSearchKeys() {
    List<Content> contentList = new ArrayList<Content>();
    // The query
    String selectQuery = "SELECT  * FROM " + TABLE_SEARCH;

    SQLiteDatabase db = this.getWritableDatabase();
    Cursor cursor = db.rawQuery(selectQuery, null);

    // I use do.. while here and it works now, should I better use for loop?
    if (cursor.moveToFirst()) {
        do {
            Content content = new Content();
            content.setID(Integer.parseInt(cursor.getString(0)));
            content.setsKeys(cursor.getString(1));
            content.setAct(cursor.getString(2));
            // Adding content to list
            contentList.add(content);
        } while (cursor.moveToNext());
    }
    // return content list
    return contentList;
}

The problem now is how to pass the result of above function into String[] ? In my Activity I try to use it like this and it's not working:

(Updated)

...
setContentView(R.layout.page_search);

    DatabaseHandler db = new DatabaseHandler(this);
    List<Content> contents = db.getAllContacts(); 
    final String[] searchQ = new String[contents.size()];
    int i =0;

      for (Content cn : contents) {
            searchQ[i] = cn.getsKeys().toString(); 
      }

      final String[] SearchQueries = searchQ;

If I comment the code above and change it to string array like this, then it works:

static final String[] SearchQueries = new String[] { "iPhone", "Mac", "Apple",};

My aim is to replace array above into Array I retrieve from my database. So what's wrong and what's the correct method to handle this? Many thanks for your help.

Vincent Mimoun-Prat · Accepted Answer · 2012-11-08 14:10:43Z

1

Problem 1: if cursor is empty but not null, your do while loop fails (change it to a while loop)

Problem 2: to convert to string, you'll need a toString method in your Content class. Then you will write a loop:

String[] queryAsStrings = new String[query.size()];
int i = 0;
for (Content c : query) {
  queryAsStrings[i] = c.toString();
}

answered Nov 8, 2012 at 14:10

Vincent Mimoun-Prat

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2 Comments

Nebliena Over a year ago

Thanks MarvinLab, but I don't get it. The getAllKey function above is also not working anyway. I need a proper function and test it to see if it's working. After it's confirmed working, I can move on with the converting. Unfortunately this doesn't seem to be easy for a newbie like me :/

Nebliena Over a year ago

Marvin look at my updated code above, I try to do like what you said, but still no luck. Could you help me more, please? Thanks for your responds

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