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How to know the moment when Data in database changed (ActiveAndroid ORM)?

I have a HTTP Server and Android app.
All data -> JSON format. For mapping used Gson.
ORM - ActiveAndroid.
The problem : I need something like an observer/notifier object, which can told me, that a row in database updated just now.
Something like this :
public void interface Observable<T> {
void onItemUpdated(T item);
}
So I looking a solution. I've read ActiveAndroid docs, but it doesn't get to me any result. Maybe i can mix something with ContentObserver or something like this?

How about to create a logging table where you can append a row for each update.
It has the insertion cost but select query is so fast. And also you can store update history of each record if you want or delete the log record if you are worry about performance.

you can create new field in your db which holds the updated date and time and after every operations in db you may query the db about the recent updates done to your db

You can accomplish this by implementing your own ContentObserver for the URI of the table you want to be notified about. ActiveAndroid has its own content provider you can use or you can implement your own, that works with your tables. In one of my projects I used ActiveAndroid and had my own content provider for 3rd party apps. Upon an update/insert/deletion of a row you should be notified by content provider that something was changed with reference to some URI and if you have a registered content observer to this URI you will be notified.

Sorting search results (from Android SearchView query) by number of matches

i'm trying to find a good way to sort the search results according to relevance after performing a search with a SearchView in Android. For me relevance means the number of matches in two SQLite text columns
I'm using a CursorLoader and there the sort order can be given to the constructor at the end
CursorLoader tLoader = new CursorLoader(
getActivity(), ContentProviderM.ARTICLE_CONTENT_URI,
tProj, tSel, tSelArgs, SORT_ORDER);
(or set using the setSortOrder (String sortOrder) method)
But i need more flexibility than this because i'm looking to sort on the number of matches rather than just on one or two columns
The only solution i can see myself is to add another column in my SQLite table, do some processing, and supply that column as the sort column to the CursorLoader
Now for my question: What is the best way to supply the sort order information to the CursorLoader using SQLite syntax, avoiding having to add a new column? (And what could this SQLite code look like?) Also, i'd like to ask more in general: Is there a different solution to this problem that i've missed?
Grateful for any help! And with kind regards,
Tord

Depending on the content provider, if it just pass to the orderBy field, you can do anything.
SQLiteDatabase query
orderBy How to order the rows, formatted as an SQL ORDER BY clause
(excluding the ORDER BY itself). Passing null will use the default
sort order, which may be unordered.
you can do whatever you want, this is just the line after ORDER BY
P.S. It is totally depending on the Content Provider, it it choose to ignore the parameter, you can do nothing.

i found a "workaround" for this problem.
After investigating different ways to write sqlite code i ended up just adding a new table column just for sorting. This column simply stores an integer and is updated every time that the user performs a search, right before the CursorLoader is created
Advantages:
We can now do all of the relevance calculations in Java code
Drawbacks:
Relevance calculation is done as the search is done so if we have a large number of items it may take some time to process everything

SearchManager - adding custom suggestions

I've read all of the documentation online about building search interfaces and adding custom suggestions... but I'm still unclear on how this works. The documentation says that I must "Build a table (such as in an SQLiteDatabase) for your suggestions and format the table with required columns". I'm assuming the system will eventually fill this table with the appropriate suggestions on its own... but which process/class is responsible for this, and when will the actual insertions occur (before any query is made by the user, after a query has been made by the user, etc.)?
And while I'm asking a question up here, if someone could clarify the difference between an AutoCompleteTextView and a SearchView w/ custom suggestions... that'd be awesome. AutoCompleteTextView seems suspiciously easy to implement compared to the SearchView (which requires changes to be made to the ContentProvider, SQLiteDatabase helper class, etc.).

You have to create a content provider which delivers your custom suggestions based on a query so far entered in the search view. In your searchable.xml you configure the minimum length of the search expression, which must be reached before asking for suggestions. This content provider is called a suggestion provider (it still extends ContentProvider). The content provider's authority is also configured in searchable.xml.
There is no limitation on how the suggestion provider computes its suggestions. You can search the web query a database or read a file. But the answer to the query is in the format of a table. If the suggestions is directly queried from a database you can use the cursor answered by the database query to deliver the result in the content provider's query() method. If the result is computed from one or more sources you can create a table on the fly by using a MatrixCursor.
The rows of the answer from the suggestion provider are used by the search mechanism to display the suggestion, they are stored in a table. The format of the rows is as follows:
private static final String[] COLUMNS = {
"_id",
SearchManager.SUGGEST_COLUMN_ICON_1, // ID of a drawable (icon) as String
SearchManager.SUGGEST_COLUMN_TEXT_1, // main text for suggestion display
SearchManager.SUGGEST_COLUMN_TEXT_2, // secondary text for suggestion display
SearchManager.SUGGEST_COLUMN_INTENT_DATA, // this could be an URI to access the suggestion as used in an intent with a VIEW action
SearchManager.SUGGEST_COLUMN_INTENT_ACTION, // this could be Intent.ACTION_VIEW
SearchManager.SUGGEST_COLUMN_SHORTCUT_ID // e.g. SearchManager.SUGGEST_NEVER_MAKE_SHORTCUT
};
Searching is described here in more detail: http://developer.android.com/guide/topics/search/index.html

Retrieving Database Information and Showing in ListView with Android

I am working on an Android app that will allow the user to see restaurants in the city I live in. I am storing each restaurants information (name, address, telephone, hours, category, website) in an SQLite database.
What I am trying to do is to create a SortByAlpha activity that will list the restaurants by name in alphetically-descending order.
I understand that I should be using a Cursor to do this but I can't find a half decent tutorial, all of the "tutorials" I find are a bunch of code with minimal explanation. How can I do this / Where can I find a good tutorial?

Use SimpleCursorAdapter, which bridges between Cursor and Adapter. Here is an example how to use it: http://developer.android.com/guide/topics/ui/binding.html

I would advise creating a "Restaurant" class that contains all the fields you will be listing. Then make your SQL call and specify "ORDER BY Name". Then create an ArrayList that can be fed to your custom list adapter! Also, if they were to somehow get out of order, just implement the "Comparable" interface for the Restaurant class and compare based on "Name" and then you can call Collections.sort(restaurantlist); to sort them in alphabetical order. I personally think ORDER BY is the easier way to go!

Content Provider filtering query, filtering Cursor

I got following problem, I need to use a Content Provider to read a
Database of an other App.
first I want all rows, and after analyzing the data only e.g. the rows
from _id = 1, 3 and 5.
how can I call a Content provider and select only these rows?
or is it possible to create a subset Cursor form an given Cursor?
Thanks in advance.

If you're talking to another app, I assume you're querying the other app's ContentProvider to get the data from them in the first place.
In this situation, the cleanest answer seems not to build your own ContentProvider that filters/wraps theirs. Instead query their ContentProvider from your application directly, and use the select clause in your query() to specify the conditions that define the subset of data you want to be given.