domen
domen

Reputation: 1279

Displaying 100000+ items in ListView from SQLite database

I'm trying to display all the items from a pre-filled database (with over 100000 rows) in a ListView using cursors. It works, but it takes a couple of minutes for the app to start and show the ListView. Is there a faster way? I've read something about FTS3 tables, would that help?

I'm using ArrayList<HashMap<String, String>> with a SimpleAdapter and custom 2-line layout. Code:

Cursor cursor = sDictionary.query("FTSgesla", new String[] {PodatkovnaBaza.KEY_WORD, PodatkovnaBaza.KEY_DEFINITION}, null, null, null, null, PodatkovnaBaza.KEY_WORD);

    if (cursor == null) 
    {

            // There are no results
            mTextView.setText("Empty");
    } 
    else 
    {

        HashMap<String, String> item;

        if(cursor.moveToFirst())
        {
            do
            {
                item = new HashMap<String, String>();
                item.put("line1", cursor.getString(0));
                item.put("line2", cursor.getString(1));
                list.add(item);
            }
            while(cursor.moveToNext());
        }

            sa = new SimpleAdapter(GlavniActivity.this, list,
                    R.layout.result,
                    new String[] { "line1","line2" },
                    new int[] {R.id.word, R.id.definition});

            mListView.setAdapter(sa);
            // Define the on-click listener for the list items
            mListView.setOnItemClickListener(new OnItemClickListener() {

                @Override
                public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                   //do something
                }
            });
        }

Upvotes: 3

Views: 1817

Answers (4)

Gabe Sechan
Gabe Sechan

Reputation: 93561

Why are you ever loading 100K items into a listview? A listview is an onscreen element that will be interacted with by a user. Nobody is ever going to scroll through 100K items. Nobody will even scroll through 1% of that. The answer here is to not load them all.

Upvotes: 0

Jachu
Jachu

Reputation: 435

I am not very sure, but I am afraid your problem is you are loading 100.000 views at the same time. Personally I would use ArrayAdapter or base adapter, overriden getView(..) method, and of course using ViewHolder pattern.

Here you got an example very smooth and fast using BaseAdapter: https://github.com/Jachu5/RSS_Feeder_Android/tree/master/RssFeeder_sherlock/src/com/example/adapter

Hope it helps!

Upvotes: 0

draksia
draksia

Reputation: 2371

This should be in sections with some kind of filtering, loading that many items just seems why to excessive.

Upvotes: 0

wtsang02
wtsang02

Reputation: 18863

There are no faster way to load 100000 items, and your user will also not need to see all at once, hence, load them one-by-one with thread.

    private class SQLTask extends AsyncTask<Integer, String[], Integer> {

    @Override
    protected Integer doInBackground(Integer... params) {
        db.open();
        Cursor c = db.getAllDataCursor();
        for (c.moveToFirst(); !c.isAfterLast(); c.moveToNext()) {
            String[] temp = new String[c.getColumnCount()];
            for (int i = 0; i < temp.length; i++) {
                temp[i] = c.getString(i);
            }
            publishProgress(thisTask, temp);
        }
        c.close();
        db.close();
    }

    @Override
    protected void onProgressUpdate(String[]... values) {
        super.onProgressUpdate(values);
        // LOAD ONE ROW
    }
}

Upvotes: 7

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