Bi-Directional Sync on Android Using SyncAdapter

Question

I am planning to create sqlite table on my android app. The data comes from the the server via webservice.

I would like to know what is the best way to do this. Should I transfer the data from the webservice in a sqlite db file and merge it or should i get all the data as a soap request and parse it in to table or should I use rest call.

The general size of the data is 2MB with 100 columns.

Please advise the best case where I can quickly get this data, with less load on the device.

My Workflow is:

1. Download a set of 20000 Addresses and save them to device sqlite database. This operation is only once, when you run the app for the first time or when you want to refresh the whole app data.
2. Update this record when ever there is a change in the server.
3. Now I can get this data either in JSON, XML or as pure SqLite File from the server . I want to know what is the fastest way to store this data in to Android Database.

I tried all the above methods and I found getting the database file from server and copying that data to the database is faster than getting the data in XML or JSON and parsing it. Please advise if I am right or wrong.

Answer 1

If you are planning to use sync adapters then you will need to implement a content provider (or atleast a stub) and an authenticator. Here is a good example that you can follow.

Also, you have not explained more about what is the use-case of such a web-service to decide what web-service architecture to suggest. But REST is a good style to write your services and using JSON over XML is advisable due to data format efficiency (or better yet give protocol-buffer a shot)

And yes, sync adapters are better to use as they already provide a great set of features that you will want to implement otherwise when written as a background service (e.g., periodic sync, auto sync, exponential backoff etc.)

To have less load on the device you can implement a sync-adapter backed by a content provider. You serialize/deserialize data when you upload/download data from server. When you need to persist data from the server you can use the bulkInsert() method in content-provider and persist all your data in a transaction