Develop Reference

android cursorloader with db from different activity

I access a db in an activity that is used in a different activity. However when i use getContentResolver.update() on the db it won't update in my CursorLoader although it accesses the same db (it's the same queryUri). It shows me the updated value when i dump a query to the db, however the CursorLoader won't.
Here is my onCreateLoader method:
#Override
public Loader<Cursor> onCreateLoader(int id, Bundle args) {
Uri queryUri;
if(id == ID_LOADER_PORTFOLIO) {
String[] projection = null;
String selection = null;
String[] selectionArguments = null;
queryUri = MainFeedContract.CONTENT_URI;
return new CursorLoader(this,
queryUri,
MainActivity.COLUMN_NAMES,
selection,
selectionArguments,
null);
}
return null;
}
and this is my call to update the db in the same activity:
portfolioBuilder
.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
})
.setPositiveButton("Apply",new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
EditText et_newValue = (EditText) view.findViewById(R.id.et_portfolio);
Double value = Double.valueOf(et_newValue.getText().toString());
String selectedSpinnerCurrency = spinner.getSelectedItem().toString();
ContentValues cv = new ContentValues();
cv.put("units",value);
getContentResolver().update(MainFeedContract.CONTENT_URI, cv, "name=?", new String[]{selectedSpinnerCurrency});
Log.d("QUERY", DatabaseUtils.dumpCursorToString(getContentResolver().query(MainFeedContract.CONTENT_URI, null, null, null, null)));
}
});
Am i making a mistake when trying to update the db? :/

You may need to register a ContentObserver
Call this method in onResume()
public void registerDataObserver() {
try {
getContext().getContentResolver().registerContentObserver(MainFeedContract.CONTENT_URI, true, new DataObserver(new Handler()));
} catch (IllegalStateException ise) {
}
}
DataObserver class
class DataObserver extends ContentObserver {
public DataObserver(Handler handler) {
super(handler);
}
#Override
public void onChange(boolean selfChange, Uri uri) {
getLoaderManager().restartLoader(0, null, this);
}
}

How to wait asynchronus method on android

I have this class to connect with twitter
public class TwitterConnect {
TwitterApiClient twitterApiClient;
StatusesService statusesService;
Long [] ids;
public TwitterConnect(){
twitterApiClient = TwitterCore.getInstance().getApiClient();
statusesService = twitterApiClient.getStatusesService();
callHomeTimeLine();
}
private void callHomeTimeLine(){
statusesService.homeTimeline(200, null, null, null, null, null, null, new Callback<List<Tweet>>() {
#Override
public void success(Result<List<Tweet>> result) {
Long [] ids = new Long[result.data.size()];
int i=0;
for (Tweet tweet:result.data) {
//tweet.id;
Log.w("Twwet",tweet.id+" ");
ids[i] = result.data.get(i).id;
i++;
}
setIds(ids);
}
#Override
public void failure(TwitterException exception) {
Log.e("FAILURE", "Fallo en callHomeTimeLine");
}
});
}
private void setIds(Long [] ids){
this.ids = ids;
}
public Long[] getIds() {
return ids;
}
}
And I use this clas on an activity
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_following);
getSupportActionBar().setDisplayShowTitleEnabled(false);
TwitterConnect twc = new TwitterConnect();
this.ids = twc.getIds()//ids its always null
;
But the this.ids is always null,on succces method its asynchronous ,how I can wait for it? In edbug mode ,the data is correctly retrieved but the activity uses the ids array before the asynchronous method finished.

The common way to "wait" for an asynchronous task to finish is (in your case), like this:
In your TwitterConnect Class, add an interface:
interface Idsinterface {
void setIds(Long[] ids);
}
and pass it as parameter to TwitterConnect Constructor, that it looks like this:
public class TwitterConnect {
TwitterApiClient twitterApiClient;
StatusesService statusesService;
Long [] ids;
public TwitterConnect(IdsInterface idsInterface){
twitterApiClient = TwitterCore.getInstance().getApiClient();
statusesService = twitterApiClient.getStatusesService();
callHomeTimeLine(idsInterface);
}
private void callHomeTimeLine(IdsInterface idsInterface){
statusesService.homeTimeline(200, null, null, null, null, null, null, new Callback<List<Tweet>>() {
#Override
public void success(Result<List<Tweet>> result) {
Long [] ids = new Long[result.data.size()];
int i=0;
for (Tweet tweet:result.data) {
//tweet.id;
Log.w("Twwet",tweet.id+" ");
ids[i] = result.data.get(i).id;
i++;
}
idsInterface.setIds(ids);
}
#Override
public void failure(TwitterException exception) {
Log.e("FAILURE", "Fallo en callHomeTimeLine");
}
});
}
private void setIds(Long [] ids){
this.ids = ids;
}
public Long[] getIds() {
return ids;
}
interface IdsInterface {
void setIds(Long[] ids);
}
}
Now you can use this Class like this:
new TwitterConnect(TwitterConnect.IdsInterface() {
#Override
void setIds(Long[] ids) {
YourActivity.this.ids = ids;
//rest of your code here
});

Lag in AutocompleteTextView from Sqlite Database having over million records

I am fetching records into adapter using addTextChangedListener. If I query through database asynchronously, then there is no lag but I am not getting suggestions in my AutocompleteTextView as soon as I enter the word and if I query on UI thread then there is a serious lag. I already indexed my table.
How can I improve my sqlite database performance.
Query
String where =x+" LIKE ?";
String[] whereArgs = new String[] {column_name+"%"};
cursor = db.query(TABLE_NAME,TABLE_COLUMNS,where,whereArgs, null, null, null, "10");
Asynctask
private class FindText extends AsyncTask<String, Void, Void>
{
private ArrayList<TextModel> textModels;
#Override
protected void onPreExecute() {
super.onPreExecute();
startSppiner("", "", false);
}
#Override
protected Void doInBackground(String... params) {
textModel= new StoreFactory(mActivity, 0).getSchedulesByWordSpecific(params[0].trim());
return null;
}
#Override
protected void onPostExecute(Void result) {
stopSppiner();
for(TextModel textModel: textModels)
{
mAdapter.add(textModel.getWord());
textMap.put(textModel.getText(), textModel);
}
mAdapter.notifyDataSetChanged();
}
}

How to update ListView from AsyncTask?

I am loading images by using AsyncTask and for updating ListView I am using notifyDataSetChanged() method.
But notifyDataSetChanged() doesn't change anything in the ListView onProgressUpdate().
I don't want to use cursor.requery because it is deprecated method.
Why notifyDataSetChanged() is not working for me?
public class News extends BasicActivity implements OnItemClickListener{
private SQLiteDatabase db = null;
private ListView lvNews;
private TaskImgSm taskImgSm = null;
private NewsListAdapter adapter;
private Cursor cur;
boolean pause = false;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.news);
db = SQLiteDatabase.openDatabase(((MyApp) getApplication()).getDbPath(), null, SQLiteDatabase.OPEN_READWRITE);
lvNews = (ListView) findViewById(R.id.list_news);
lvNews.setOnItemClickListener(this);
listFilling();
if (taskImgSm != null && taskImgSm.getStatus() != AsyncTask.Status.FINISHED) taskImgSm.cancel(true);
taskImgSm = new TaskImgSm();
taskImgSm.execute();
}
private void listFilling() {
cur = db.query("news", new String[] { "_id", "id_news", "title", "date", "img_url", "img_sm" }, null, null, null, null, null);
startManagingCursor(cur);
adapter = new NewsListAdapter(this, cur, db);
lvNews.setAdapter(adapter);
adapter.notifyDataSetChanged();
}
class TaskImgSm extends AsyncTask<Void, String, Void> {
Cursor curs;
#Override
protected void onPreExecute() {
super.onPreExecute();
curs = db.query("news", new String[] { "_id", "id_news", "img_url", "img_sm" }, null, null, null, null, null);
startManagingCursor(curs);
}
#Override
protected Void doInBackground(Void... unused) {
curs.moveToFirst();
while (curs.isAfterLast() == false) {
if (curs.getBlob(curs.getColumnIndex("img_sm")) == null) {
String imgUrl = curs.getString(curs.getColumnIndex("img_url"));
String idNews = curs.getString(curs.getColumnIndex("id_news"));
updateImg(imgUrl, idNews, "img_sm");
publishProgress();
}
curs.moveToNext();
}
return (null);
}
private void updateImg(String img_URL, String whereId, String imgColumn) {
try {
DefaultHttpClient mHttpClient = new DefaultHttpClient();
HttpGet mHttpGet = new HttpGet();
mHttpGet.setURI(new URI(img_URL));
HttpResponse mHttpResponse = mHttpClient.execute(mHttpGet);
if (mHttpResponse.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
HttpEntity entity = mHttpResponse.getEntity();
if (entity != null) {
// insert to database
ContentValues values = new ContentValues();
values.put(imgColumn, EntityUtils.toByteArray(entity));
db.update("news", values, "id_news=" + whereId, null);
}
}
} catch (URISyntaxException e) {e.printStackTrace();
} catch (ClientProtocolException e) {e.printStackTrace();
} catch (IOException e) {e.printStackTrace();}
}
#Override
protected void onProgressUpdate(String... item) {
if (pause == false) {
adapter.notifyDataSetChanged();
}
}
#Override
protected void onPostExecute(Void unused) {}
}
#Override
protected void onPause() {
pause = true;
super.onPause();
}
#Override
protected void onResume() {
pause = false;
adapter.notifyDataSetChanged();
super.onResume();
}
#Override
protected void onDestroy() {
if (taskImgSm != null && taskImgSm.getStatus() != AsyncTask.Status.FINISHED) taskImgSm.cancel(true);
super.onDestroy();
}
}

The reason it's not working is because notifyDataSetChanged() only tells the ListView that the data in the adapter has changed. Since that data hasn't changed (because you haven't queried the database again), then the ListView won't show any updates. You need to execute the query again and update the data in the adapter, then call notifyDatasetChanged().

Why don't use a ContentProvider.
With a ContentProvider you can update your table with the notifyChange(uri) method
Tutorial for that here http://thinkandroid.wordpress.com/2010/01/13/writing-your-own-contentprovider/

I think you may want to update the ImageView in a ListView in the onPostExecute() method. This is how I accomplished something similar to what you are doing : Multithreading For Performance

I have problems when using sqlite inside AsyncTask in android?

I face two main problems when using a sqlite command inside an AsncTask in android.
When I execute a select command on the first try I get no results but on the second try (loading a activity that has this Asynctask) I do get results.
Sometimes I get an error that the database is not closed despite that it is already closed/
What is the problem with this?
UPDATE:
This is the code that retrive data from database (db.getAllMessage)
private ArrayList<FriendMessagesResulted> getMessagesFromCach(Context c){
FriendMessagesResulted messagesResulted1 = new FriendMessagesResulted();
DBAdapter db = new DBAdapter(c);
Cursor c1;
db.open();
c1 = db.getAllMessage(Settings.getCurrentUserId(c),Integer.parseInt(fId));
Log.d("***Database count",c1.getCount()+" from: "+Settings.getCurrentUserId(c)+" to:"+Integer.parseInt(fId));
c1.moveToFirst();
if(c1.getCount()>0)
status=true;
if (messagesResultedList == null) {
messagesResultedList = new ArrayList<FriendMessagesResulted>();
}
else
messagesResultedList.clear();
while (c1.isAfterLast() == false) {
if(Integer.parseInt(c1.getString(0))>maxId)
maxId=Integer.parseInt(c1.getString(0));
messagesResulted1.set_mId(Integer.parseInt(c1.getString(0)));
messagesResulted1.set_msgTxt("MD:"+c1.getString(3));
messagesResulted1.set_MessageTime(c1.getString(4));
messagesResulted1.set_dir(c1.getString(5));
messagesResultedList.add(messagesResulted1);
c1.moveToNext();
}
db.close();
c1.close();
return messagesResultedList;
}
and this the code for AsyncTask, where I call get getMessagesFromCach method
private void getMessages(final Context c)
{
handler = new Handler();
r=new Runnable() {
public void run() {
class RecentMessageLoader extends AsyncTask<Void, Void, ArrayList<FriendMessagesResulted>>{
ArrayList<FriendMessagesResulted> messagesResultedList=null;
#Override
protected ArrayList<FriendMessagesResulted> doInBackground(Void... params) {
if(!finishLoadingPastMessages)
{
messagesResultedList=getMessagesFromCach(c);
if(!status){
Log.d("Where are you","I'm in JSON");
messagesResultedList=getMessagesFromJSON(c);
}
}
else{
Log.d("Where are you","I'm in Recent messages");
messagesResultedList=getRecentMessages(c,Settings.getCurrentUserId(c),Integer.parseInt(fId));
}
return messagesResultedList;
}
protected void onPostExecute( ArrayList<FriendMessagesResulted> FMRList ) {
// to disappear loading message
d.dismiss();
finishLoadingPastMessages=true;
if(FMRList!=null){
for(int i=FMRList.size()-1;i>=0;i--)
addMessage(FMRList.get(i),c);
}
handler.postDelayed(r, 2000);
}
}
new RecentMessageLoader().execute();
}
};
handler.post(r);
}
UPDATE 2 : Cach class ..
public class Cach {
static DBAdapter db;
public Cach(Context c)
{
}
public static void AddMessages(Context c,
int id,
int fromId,
int toId,
String message,
String dir,
String MessageTime)
{
db = new DBAdapter(c);
db.open();
long id2;
id2 = db.insertMessage(id, fromId, toId, message, dir,MessageTime);
db.close();
}
}

It seems the problem is with the type of variables you are using.. there must be Static variables of instance variables which are getting set from many sources... try not to use static variables and use local variables I mean in the methods implicitly.