How to properly insert values into the SQLite database using ContentProvider's insert() method through a CursorLoader?

Question

I was reading the doc, but I am still not too sure. Its says to use `getContentResolver()`, but then that really isn't using CursorLoader. So is there a way to do it through `CursorLoader`? I know how to do it with `query()`. Are the steps very similar? Even just a link that explains exactly this would be helpful. Please note, do not link me to the Google doc as they do not have an example that ever uses the `insert()` method from ContentProvider using a `CursorLoader`. Thanks in advance!! Edit: I should probably mention the reason I am confused with this is because calling a new `CursorLoader` automatically calls `ContentProviders` `query()` method. But how can I do the same for insert?

Accepted Answer

Check out my blog post on the subject:

Content Resolvers and Content Providers

The `CursorLoader` has nothing to do with it.

Insertion is a totally different concept... it has absolutely nothing to do with the `CursorLoader`. When coupled with the `LoaderManager`, the `CursorLoader` automatically queries your database and updates itself when the `ContentObserver` is notified of a datastore change. It has nothing to do with the actual process of inserting data into your database.

How requests to the `ContentResolver` are resolved

When you insert (or query or update or delete) data into your database via the content provider, you don't communicate with the provider directly. Instead, you use the `ContentResolver` object to communicate with the provider (note that the `ContentResolver` is a private instance variable in your application's global `Context`) . More specifically, the sequence of steps performed is:

You call `getContentResolver().insert(Uri, ContentValues);`

The `ContentResolver` object determines the authority of the Uri.

The `ContentResolver` relays the request to the content provider registered with the authority (this is why you need to specify the authority in the `AndroidManifest.xml`).

The content provider receives the request and performs the specified operation (in this case `insert`). How and where the data is inserted depends on how you implemented the `insert` method (`ContentProvider` is an abstract class that requires the user to implement `insert`, `query`, `delete`, `update`, and `getType`).

Hopefully you were able to wrap your head around that at least a little. The reason why there are so many steps involved is because Android (1) allows applications to have more than one content provider, and (2) needs to ensure that apps can securely share data with other third-party apps. (It wasn't because it wanted to confuse you, I promise).

Inserting data via the `ContentProvider`

Now that you (hopefully) have a better idea of how the `ContentResolver` is able to relay these requests to the content provider, inserting the data is fairly straight forward:

First, decide which uri you want to have matched by your content provider. This depends on how you decided to match your uris with the `UriMatcher`. Each uri you have represents a different means of inserting data into your internal database (i.e. if your app has two tables, you will probably have two uris, one for each table).

Create a new `ContentValues` object and use it to package the data you wish to send to the content provider. The `ContentValues` object maps column names to data values. In the below example, the column name is "column_1" and the value being inserted under that column is "value_1":

```
ContentValues values = new ContentValues();
values.put("column_1", "value_1");
```

Once received, the content provider will (in your case) pass the `values` object to your `SQLiteDatabase` (via the `SQLiteDatabase.insert(String table, String nullColumnHack, ContentValues values)` method). Unlike the `ContentProvider`, this method is implemented for you... the `SQLiteDatabase` knows how to handle the `values` object and will insert the row into the database, returning the row id of the inserted row, or `-1` if the insertion failed.

... and that's how you insert data into your database.

TL;DR

Use `getContentResolver().insert(Uri, ContentValues);`

How to properly insert values into the SQLite database using ContentProvider's insert() method through a CursorLoader?

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