1page.title=Transferring Data Using Sync Adapters 2 3trainingnavtop=true 4startpage=true 5 6 7@jd:body 8 9<div id="tb-wrapper"> 10<div id="tb"> 11 12<h2>Dependencies and prerequisites</h2> 13<ul> 14 <li>Android 2.1 (API Level 7) or higher</li> 15</ul> 16 17<h2>You should also read</h2> 18<ul> 19 <li> 20 <a href="{@docRoot}guide/components/bound-services.html">Bound Services</a> 21 </li> 22 <li> 23 <a href="{@docRoot}guide/topics/providers/content-providers.html">Content Providers</a> 24 </li> 25 <li> 26 <a href="{@docRoot}training/id-auth/custom_auth.html">Creating a Custom Account Type</a> 27 </li> 28</ul> 29 30<h2>Try it out</h2> 31 32<div class="download-box"> 33 <a href="http://developer.android.com/shareables/training/BasicSyncAdapter.zip" class="button">Download the sample</a> 34 <p class="filename">BasicSyncAdapter.zip</p> 35</div> 36 37</div> 38</div> 39<p> 40 Synchronizing data between an Android device and web servers can make your application 41 significantly more useful and compelling for your users. For example, transferring data to a web 42 server makes a useful backup, and transferring data from a server makes it available to the user 43 even when the device is offline. In some cases, users may find it easier to enter and edit their 44 data in a web interface and then have that data available on their device, or they may want to 45 collect data over time and then upload it to a central storage area. 46</p> 47<p> 48 Although you can design your own system for doing data transfers in your app, you should 49 consider using Android's sync adapter framework. This framework helps manage and automate data 50 transfers, and coordinates synchronization operations across different apps. When you use 51 this framework, you can take advantage of several features that aren't available to data 52 transfer schemes you design yourself: 53</p> 54<dl> 55 <dt> 56 Plug-in architecture 57 </dt> 58 <dd> 59 Allows you to add data transfer code to the system in the form of callable components. 60 </dd> 61 <dt> 62 Automated execution 63 </dt> 64 <dd> 65 Allows you to automate data transfer based on a variety of criteria, including data changes, 66 elapsed time, or time of day. In addition, the system adds transfers that are unable to 67 run to a queue, and runs them when possible. 68 </dd> 69 <dt> 70 Automated network checking 71 </dt> 72 <dd> 73 The system only runs your data transfer when the device has network connectivity. 74 </dd> 75 <dt> 76 Improved battery performance 77 </dt> 78 <dd> 79 Allows you to centralize all of your app's data transfer tasks in one place, so that they 80 all run at the same time. Your data transfer is also scheduled in conjunction with data 81 transfers from other apps. These factors reduce the number of times the system has to 82 switch on the network, which reduces battery usage. 83 </dd> 84 <dt> 85 Account management and authentication 86 </dt> 87 <dd> 88 If your app requires user credentials or server login, you can optionally 89 integrate account management and authentication into your data transfer. 90 </dd> 91</dl> 92<p> 93 This class shows you how to create a sync adapter and the bound {@link android.app.Service} that 94 wraps it, how to provide the other components that help you plug the sync adapter into the 95 framework, and how to run the sync adapter to run in various ways. 96</p> 97<p class="note"> 98 <strong>Note:</strong> Sync adapters run asynchronously, so you should use them with the 99 expectation that they transfer data regularly and efficiently, but not instantaneously. If 100 you need to do real-time data transfer, you should do it in an {@link android.os.AsyncTask} or 101 an {@link android.app.IntentService}. 102</p> 103<h2>Lessons</h2> 104<dl> 105 <dt> 106 <b><a href="creating-authenticator.html">Creating a Stub Authenticator</a></b> 107 </dt> 108 <dd> 109 Learn how to add an account-handling component that the sync adapter framework expects to be 110 part of your app. This lesson shows you how to create a stub authentication component for 111 simplicity. 112 </dd> 113 <dt> 114 <b><a href="creating-stub-provider.html">Creating a Stub Content Provider</a></b> 115 </dt> 116 <dd> 117 Learn how to add a content provider component that the sync adapter framework expects to be 118 part of your app. This lesson assumes that your app doesn't use a content provider, so it 119 shows you how to add a stub component. If you have a content provider already in your app, 120 you can skip this lesson. 121 </dd> 122 <dt> 123 <b><a href="creating-sync-adapter.html">Creating a Sync Adapter</a></b> 124 </dt> 125 <dd> 126 Learn how to encapsulate your data transfer code in a component that the sync 127 adapter framework can run automatically. 128 </dd> 129 <dt> 130 <b><a href="running-sync-adapter.html">Running a Sync Adapter</a></b> 131 </dt> 132 <dd> 133 Learn how to trigger and schedule data transfers using the sync adapter framework. 134 </dd> 135</dl> 136