![\"image01\"](\"\/wp-content\/uploads\/sites\/44\/2019\/04\/image01.png\")
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Dropbox released a new API for mobile app developers yesterday at their DBX<\/a> conference: a Datastore API<\/a> which allows you to sync data between a user\u2019s devices in real-time, via their dropbox account.<\/p>\n As soon as the keynote ended, we rushed back to Xamarin HQ and dove right in. We decided to write a simple iOS app that would sync the positions of various cute monkeys between devices. Our app is written in C# and it\u2019s called MonkeyBox. Check it out:<\/p>\n Arrange the monkeys to your satisfaction, scale and rotate them, and watch them sync automatically across all your devices. You can browse the MonkeyBox code by adding the Dropbox Sync component<\/a> to your project, or check it out on Github<\/a>.<\/p>\n Ok, let\u2019s take a look at the Datastore API.<\/p>\n The first step is to get the user to authorize their Dropbox account. Here\u2019s how you do that:<\/p>\n You can get your Dropbox App Key and Sync key from your app\u2019s \u201cSettings\u201d page in the App Console<\/a>. \u00a0The code above will pop up a Dropbox login view, or launch the Dropbox app if it is installed, to prompt the user to link with Dropbox. You\u2019ll need to do some additional work<\/a> to handle returning back to your app.<\/p>\n Ok, now we need to create a datastore. A datastore contains tables, and tables contain records. A record is a key-value pair, and values can be strings, ints, bools, or even a list of simple objects. Datastores have no schema and so each record can have an arbitrary set of value fields.<\/p>\n Here\u2019s how we open the datastore:<\/p>\n Note that we called Sync() after getting a handle to the datastore. Whenever you call the Sync() method on a datastore, it will save your changes to Dropbox, and also pull any changes made on other devices. Conflicts are handled automatically using a configurable rules engine<\/a>. Remember to call Sync before using a datastore to make sure you have a local copy of the data!<\/p>\n Now that we have access to our store, and have the data sync\u2019d locally, we can look up values in our monkeys table:<\/p>\n And here\u2019s how you store a new value:<\/p>\n You can also ask Dropbox to notify you when things change:<\/p>\n That\u2019s about it! A pretty simple API.<\/p>\n If you want to check out your datastore values on the web, Dropbox\u2019s App Console<\/a> now features a \u201cBrowse datastores\u201d link in your app\u2019s settings. It exposes a read-only view of the records in the store.<\/p>\n Here are some of the records from our monkey application\u2019s datastore:<\/p>\n In conclusion, we think the datastore opens up some amazing new capabilities for your cross-platform apps. We\u2019re fans, and will be eager to see how it evolves. Thanks to our partners at Dropbox<\/a> for a great event and a fun new API!<\/p>\n Want to try this on your own? Install the Dropbox component<\/a> from the Xamarin Component Store into your app in one click and start syncing.<\/p>\nvar manager = new DBAccountManager (\u201cDROPBOX_APP_KEY\u201d, \u201cSYNC_KEY\u201d);\r\nvar account = manager.LinkedAccount;\r\nif (account == null)\r\n manager.LinkFromController (window.RootViewController); \/\/ logs in.\r\n<\/pre>\n
DBError error;\r\nvar store = DBDatastore.OpenDefaultStoreForAccount (account, out error);\r\nstore.Sync (null);\r\n<\/pre>\n
var table = store.GetTable (\"monkeys\");\r\nDBError error;\r\nDBRecord[] results = table.Query (null, out error);\r\nvar result = results.FirstOrDefault();\r\nvar name = result.Fields [\"Name\"].ToString (); \/\/ e.g. \u2018Bob\u2019\r\n<\/pre>\n
DBRecord record;\r\nrecords.TryGetValue (monkey.Name, out record);\r\nrecord.Update (monkey.ToDictionary ());\r\nstore.Sync (null);\r\n<\/pre>\n
store.AddObserver (store, () => {\r\n \/\/ Handle events here\r\n});\r\n<\/pre>\n![\"image00\"](\"\/wp-content\/uploads\/sites\/44\/2019\/04\/image00.png\")
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