Develop Reference

how to retrieve the sum of column values in simplecursoradapter in sqlite database

Am using db query to sum the column values by using group by clause. I can get the total amount but i couldn't display the values in simplecursoradapter. Please help me to display the total values. I have posted my code below.
String[] columns = new String[] { KEY_ID, KEY_CATEGORY,"sum("+KEY_AMOUNT+")as" + KEY_AMOUNT,
KEY_COMMENT };
Cursor cursor = db.query(TABLENAME2, columns, null, null, null, null,
null);
return cursor;
To display the values in Listview using Simplecursoradapter
String[] from = new String[] { Dailydialog.KEY_CATEGORY,
Dailydialog.KEY_AMOUNT,Dailydialog.KEY_COMMENT};
int[] to = new int[] { R.id.id2, R.id.id3,R.id.id4};
cursorAdapter1 = new SimpleCursorAdapter(this, R.layout.dailydialogall, cursor1,
from, to);
listview_dialog.setAdapter(cursorAdapter1);
Total values are not listed in Listview.

Instead of "sum("+KEY_AMOUNT+")as" + KEY_AMOUNT use " sum("+KEY_AMOUNT+") as " + KEY_AMOUNT. Notice the spaces? Its always a good idea to print your query in log. Another thing is that you need to specify group by clause as well for sum function otherwise only one row will be returned with total sum of amount of all the rows.

How to use limit and offset to page through the data

I am new to SQLite and I don't know how to use limit and offset to select a limit number of data from the database, I mean I know the query phrase, but how to use it in a cursor so I can get those data into a listview?
Currently I am using the code below to query data from the database and show them in a listview but it seems I query too much data for one query and the SQLite fail to grow, so I want to split the query into some smaller ones and do it in one time,someone suggested me to try limit and offset,but I googled it there are really not much about it on the Internet.
Would somebody kindly provide me the guide to this? an example or a tutoral, anything will do,thx
channellist = (ListView) findViewById(R.id.Channel);
mDB = new ChannelDB(this);
String[] columns = {mDB.KEY_ID, mDB.KEY_POSTER, mDB.KEY_CHANNEL, mDB.KEY_PATH, mDB.KEY_DBLINK};
String table = mDB.channelS_TABLE;
c = mDB.getHandle().query(table, columns, null, null, null, null, null);
startManagingCursor(c);
SimpleCursorAdapter adapter = new SimpleCursorAdapter(this,
R.layout.channelview,
c,
new String[] {mDB.KEY_POSTER, mDB.KEY_CHANNEL, mDB.KEY_DBLINK},
new int[] {R.id.poster, R.id.channel, R.id.douban});
adapter.setViewBinder(new ChannelViewBinder(this));
channellist.setAdapter(adapter);

pass the last argument with number as string like you need fetch 10 then you can do like this way
c = mDB.getHandle().query(table, columns, null, null, null, null, null,"10");
for more reference see How to use the LIMIT argument in an SQLite Query with Android

Display contact name ( Repeats name depends on number of contact number exists to a name)

I want to show "Contact name" and "contact number" in a list. But my code repeats "contact name" depends on how many number or other attributes (i.e. email id ) associated with that particular Name. For example .
In Contact directory contact list as..
Pankaj Kumar and numbers 000000-000 and 00000-2222. I want output as only Pankaj Kumar and primary_number, but output comes with ( Pankaj kumar and number 000000-000) and its repeat with ( Pankaj kumar and number 00000-2222).
How can I solve it..
My code is as below ..
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// We'll define a custom screen layout here (the one shown above), but
// typically, you could just use the standard ListActivity layout.
setContentView(R.layout.contacts_list_item);
Cursor mCursor = getContentResolver().query(Data.CONTENT_URI,
null, // projection
null, // selection
null, // selectionArgs
Data.DISPLAY_NAME); // sortOrder
startManagingCursor(mCursor);
// Now create a new list adapter bound to the cursor.
// SimpleListAdapter is designed for binding to a Cursor.
contactAdapter = new SimpleCursorAdapter(
this, // Context.
android.R.layout.two_line_list_item, // Specify the row template to use (here, two columns bound to the two retrieved cursor rows).
mCursor, // Pass in the cursor to bind to.
new String[] {Data.DISPLAY_NAME, ContactsContract.CommonDataKinds.Phone.NUMBER}, // Array of cursor columns to bind to.
new int[] {android.R.id.text1, android.R.id.text2}); // Parallel array of which template objects to bind to those columns.
// Bind to our new adapter.
setListAdapter(contactAdapter);
}

If you put your query as follow
Cursor cursor = getContentResolver().
query( Contacts.CONTENT_URI,
new String[]{Contacts.DISPLAY_NAME}, null, null,null);
if(cursor!=null){
while(cursor.moveToNext()){
Cursor c = getContentResolver().query(Phone.CONTENT_URI, new String[]{Phone.NUMBER, Phone.TYPE},
" DISPLAY_NAME = '"+cursor.getString(cursor.getColumnIndex(Contacts.DISPLAY_NAME))+"'", null, null);
while(c.moveToNext()){
switch(c.getInt(c.getColumnIndex(Phone.TYPE))){
case Phone.TYPE_MOBILE :break;
case Phone.TYPE_HOME :break;
case Phone.TYPE_WORK : String workNo = c.getString(c.getColumnIndex(Phone.NUMBER));break;
case Phone.TYPE_OTHER :break;
}
}
}
}
your contact name will not repeat for same number and select whichever number you want to
put as primary form mobile, work, other or home.

Query the android Mediastore for Artist names of Music files

I'm torn about how to implement this because Content Provider URI querys do not support the simple SQL "DISTINCT" query method to return a cursor to the Artists of the songs in the mediastore, removing any duplicate entries.
I can query and get a cursor to all the artists, I'm just torn as to how to remove the dupes, or simply not show them.
I've tried using matrixcursor to construct a new cursor with the dupe entries removed, but it's slow (build an array of artists, if in that array don't copy to the new matrixcursor, etc.)
Can anyone recommend a better solution, or point me in the proper direction??
I've also thought about pre-loading the information i need into an array of objects - I'm just concerned with memory overhead in my application.
Thank You for any help you may provide.

The easiest way to get a list of all the artist (and albums is the same method) is to use the MediaStore.Audio.Artist for the quest. For Example something like this would get and show all the artist:
String[] proj = {MediaStore.Audio.Artists._ID, MediaStore.Audio.Artists.ARTIST, MediaStore.Audio.Artists.NUMBER_OF_ALBUMS, MediaStore.Audio.Artists.NUMBER_OF_TRACKS };
musiccursor = managedQuery(MediaStore.Audio.Artists.EXTERNAL_CONTENT_URI, proj, null, null, MediaStore.Audio.Artists.ARTIST + " ASC");
String[] from= new String[]{ MediaStore.Audio.Artists.ARTIST, MediaStore.Audio.Artists.NUMBER_OF_ALBUMS, MediaStore.Audio.Artists.NUMBER_OF_TRACKS };
int[] to = new int[] { R.id.songname, R.id.rowlength, R.id.rowartist };
SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, R.layout.musicrow, musiccursor, from, to);
SongsView.setAdapter(adapter);
Where SongsView would be your list to display them in. Everything else is using a simple Cursor adapter
Hope this helps

You might want to try creating stateful CursorWrapper, overriding the appropriate methods. Simply ensure every call to next() iterates through the cursor until it finds an artist name you consider appropriately unique, optionally storing seen artists in an ArrayList instance variable.

ArrayList<SongBeen> genresList=new ArrayList<SongBeen>();
String value=search+ "%";
String[] inValue=new String[] {value};
ContentResolver musicResolver = activity.getContentResolver();
/*Uri musicInUri = android.provider.MediaStore.Audio.Genres.INTERNAL_CONTENT_URI;
Cursor mInternalCursor = musicResolver.query(musicInUri, null, null, null, null);
*/
Uri musicExUri = android.provider.MediaStore.Audio.Genres.EXTERNAL_CONTENT_URI;
Cursor mExternalCursor = musicResolver.query(musicExUri, null, MediaStore.Audio.Genres.NAME+ " like ?",
inValue, "LOWER(" + MediaStore.Audio.Genres.NAME + ") ASC");
Cursor[] cursors = {mExternalCursor};
final MergeCursor mMergeCursor = new MergeCursor(cursors);
if (mMergeCursor.moveToFirst()) {
do {
SongBeen been=new SongBeen();
long thisId= mMergeCursor.getLong(mMergeCursor.getColumnIndexOrThrow(MediaStore.Audio.Genres._ID));
String thisTrack = mMergeCursor.getString(mMergeCursor.getColumnIndexOrThrow(MediaStore.Audio.Genres.NAME));
been.setId(thisId);
been.setTrack(thisTrack);
genresList.add(been);
} while (mMergeCursor.moveToNext());
}
mMergeCursor.close();
return genresList;

Android SDK - List All Users

I have just begun working with the Android SDK and I am having problems with my first app. Currently, I am trying to list all of the users in a big list. However, no matter what I try, the app continues to force close. I found the code in the sample files, but this is still giving me issues. Below is the code I am using.
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
String[] projection = new String[] {
People._ID,
People._COUNT,
People.NAME,
People.NUMBER
};
//Get the base URI for the People table in the Contacts content provider.
Uri contacts = People.CONTENT_URI;
//Make the query.
Cursor managedCursor = managedQuery(contacts,
projection, // Which columns to return
null, // Which rows to return (all rows)
null, // Selection arguments (none)
// Put the results in ascending order by name
People.NAME + " ASC");
Cursor c = getContentResolver().query(Contacts.CONTENT_URI, null, null, null, null);
startManagingCursor(c);
String[] columns = new String[] {People.NAME};
int[] names = new int[] {R.id.text1};
SimpleCursorAdapter mAdapter = new SimpleCursorAdapter(this,
R.layout.main, c, columns, names);
setListAdapter(mAdapter);
}
This is directly from the sample file, yet it still errors out. I have found that the line that causes the problem is the "Cursor managedCursor = managedQuery(contacts," line. Has anyone else out there seen this? I am at a loss and have not found any solutions after 2 hours or research.
Also, I have added the following line to my app's manifest file:
<uses-permission android:name="android.permission.READ_CONTACTS"></uses-permission>
Thanks, and if you need more information please let me know.

I believe the example from the SDK docs is out of date. Try getting rid of the People._COUNT column from the cursor projection.
It's probably causing an IllegalArgumentException (see the output from adb logcat)