Download Mobile Client SDK for iOS Developer`s Guide

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Developer's Guide
<Client ID>-<Client ID Tag>
IO Exception While Connecting to Web Services
Problem
The following error occurs when performing a query:
[Mobile:5000] webservices http status: 500: IO exception while connecting
to webservices
Ensure that your device and application have a working connection with the Internet.
This error can be seen due to loss of connectivity with the Internet or Internet traffic congestion on the
handset.
Advanced Implementations
User History
The Mobile Client Sample Application includes a user history feature. It stores the results of certain
operations and allows the user to view them. When viewed, the history record displays the recognized
music, including Cover Art and the location of the user when the operation occurred.
The feature uses a local SQLite database to store the user history information.
Data Model
A simple data model is used to store the data as shown below.
Mobile Client Sample Application User History Database Data Model
To simplify interactions with the database, the implementation uses NSManagedObjectContext.
NSManagedObjectContext presents an interface to the underlying SQLite database via objects. An
object-based interface is easy to create, edit, and recall. Although the Mobile Client Sample Application
uses SQLite, NSManagedObjectContext can be used to provide an object interface to various types of
persistent storage.
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