I am developing an app which requires me to write to an SQLiteDatabase in one activity and access it from another activity . I am facing a problem implementing this. Any suggestions/ideas as to how we can share the database across multiple activities?
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I have been trying to find a discussion on the best way to handle a common sqlite database which is shared by multiple Activities (or multiple Activities and Services). This is all in the same application.
It seems that if each Activity has:
CODE:.........................
Can two or more Android Activities open an sqlite3 database for write?
I have two Activities that need to insert data into the same sqlite database. When the second Activity calls SQLiteOpenHelper.getWriteableDatabase() an IllegalStateException is thrown with the message "SQLiteDatabase created and never closed".
I've been able to avoid the Exception by making my database object a singleton but I'm thinking there must be a better way.
I'm in the middle of writing myself an app and have run into a problem concerning the use of the same SQLite database within multiple activities.
I have one activity that is used to input and store data and multiple activities that need to then read that data. Within the first activity, it has no problem inputting the data into the database, but when I go to have the other activity read the data, it tells me the database is empty. Obviously I'm doing something wrong in my handling of this shared database.
Right now, I have a DataHelper class that handles everything. In each activity, I create a DataHelper object which then calls the openOrCreateDatabase() method. I then close the database upon exiting the activity. Obviously this isn't the right way to do it.
So, my questions is, what is the correct way to set up an SQLite database in an Android application and then access it in multiple activities?
I am creating an app which allows for many different Activities to be started from a TabActivity(up to ~25). Most of the activities require data from the sqlite database, so when onCreate is run, an AsyncTask creates an SQLiteOpenHelper object(which will open a readable/writable database), runs a query, data is retrieved, and everything is then closed.
I was just testing messing around to see if i could break something, so i added every Activityto the TabActivity's TabHost. I then started mashing each tab as quickly as possible.
I noticed that very quickly i began to see in the LogCat: Caused by: android.database.sqlite.SQLiteException: database is locked: BEGIN EXCLUSIVE; and the app proceeded to die.
Typically there will only be about 4-6 tabs(i can just limit the user anyway) for the TabHost. I haven't been able to break anything with a small amount of tabs to mash, but i am still worried that maybe i am accessing the database in a poor way.
How can i prevent my SQLiteDatabase objects to cause a lock?
If i create a ContentProvider will that eliminate the possibility of database locking?
Do you have any suggestions for changes I could make for accessing data from an SQLiteDatabase?
I ended up taking the approach of using the Application class and storing 1 SQLiteOpenHelper and trying my best to keep it synchronized. This seems to be working great - i put all my 25 activities in the TabHost and mashed away on them with no errors.
I am calling ((SQLiteDbApplication)getApplication()).setDbHelper(new DBHelper(this, Constants.DB_NAME, null, Constants.DB_VERSION_CODE)); method(shown below) in every onCreate() in my activities
Any further suggestions to this approach or to the changes i made using this Application class?
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I have a todo list type application that stores all of the note data in a sqlite3 database. Each activity in the application needs access to the database to edit different parts of the data in real time.
Currently, I have each activity open its own DBManager object (the helper class I created to manage the database). This is causing problems though and I would like a slightly more global access solution so I don't have to keep opening/closing/creating a database.
I'm considering several options, and would like to hear pros and cons of each as well as other suggestions.
Singleton style. Have a wrapper class that returns a reference to the only database manager so any activity that needs it can use it.
Static Manager. Have the manager class be entirely static members and have it open the database on load. Easily accessible by anyone that needs it (which is everyone).
Merger between 1 and 2. I could make a database manager class that initializes the member singleton instance of the database and all of the data manipulation methods were static. Then I wouldn't even need a reference to the singleton to access the database.
I'm new to Android programming, and I wanted to pull list options from a column of the SQLite database for the user to select. How would I go about doing this? Like, say the database table to be read is called countries, and the columns were ID, country, and capital. How would I let the user pick from the list of capitals and have the application return the information in that row?
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What advantages of multiple activities am I missing?
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I looked into some examples of sharing data to other apps using content Provider. All these examples talks about sharing sqlite dbs. I need to share data under shared Preferences of my app to other apps using content Provider. Can I use content Provider to do that ?. Please let me know some pointers or sample code to share data other than sqlite db using content provider.
View 3 Replies View RelatedI'm new to Android, I just finished the Notepad Tutorials, where we can create SQLite Databases to save notes. So I wanted to know if it was possible to "import" my own SQLite database (not created with my App but with a 3rd-party software) to my project, and if the answer is yes, where should I save my SQLite databse and how can I have access to it.
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View 3 Replies View RelatedI have an application for which I am planning to release both a free and a paid version. I found that this will require the two versions of the application to each have different package names.
When a user upgrades from the free version to the paid version, the paid version needs to be able to access the database built by the free version. I am trying to understand the best way to make sure that upgrade does not disrupt the user's data.
I have read that the AndroidManifest file setting for shared user id should allow both applications to access the same data. I don't need the applications to both be running simultaneously, as I expect the user will uninstall the free version after upgrading to the paid version. However I need to make sure that if possible the user's data is not lost and is still accessible and usable by the paid version of the application.
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I have a class like class My data{ String name; int data; Location[] locality.
View 8 Replies View RelatedI am new to android and I have a problem in creating a database.
public class database extends ListActivity {
/** Called when the activity is first created. */
private final String MY_DATABASE_NAME = "myCoolUserDB.db";
private final String MY_DATABASE_TABLE = "t_Users";
Context c;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ArrayList<String> results = new ArrayList<String>();
setContentView(R.layout.main);
SQLiteDatabase mydb=null;
try
{
mydb.openOrCreateDatabase(MY_DATABASE_NAME, null);
} catch(Exception e){}
}}
When I run this code it throws a run time exception.
How do I delete the sqlite database exists in my android? There is a db behind my android qro and delete the same
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public void delete(String id, String name, String phonenumber, String time, String message)
{
String[] args={id};
getWritableDatabase().delete("texts", "_ID=?", args);
}
It works fine, and deletes the specified row. However, I also want to implement it so that I can delete the most recent (earliest date) entry in the database, which should be at the top of the table. I know I can do this by altering the last 2 parameters of delete, but I cannot figure out what to change them to.
Is possible update the records from SQLite from my Android Application1 from other Application2 Android
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