{"id":1186,"date":"2012-09-20T22:49:36","date_gmt":"2012-09-20T12:49:36","guid":{"rendered":"http:\/\/www.malcolmgroves.com\/blog\/?p=1186"},"modified":"2014-06-10T22:00:16","modified_gmt":"2014-06-10T12:00:16","slug":"livebindings-in-xe3-updating-objects-via-an-adapter","status":"publish","type":"post","link":"http:\/\/www.malcolmgroves.com\/blog\/?p=1186","title":{"rendered":"LiveBindings in XE3: Updating Objects via an Adapter"},"content":{"rendered":"

Where I left off in my last post<\/a>, we were able to bind our UI elements to an object, or indeed a collection of objects, by using the TAdapterBindSource combined with a TObjectBindSourceAdapter<T> or a TListBindSourceAdapter<T>.<\/p>\n

Over a few posts I want to drill a bit deeper into what happens when you make changes to those objects, specifically in this post, when you make changes via the bound controls. I’ll explore the notification system that LiveBindings uses in later posts.<\/p>\n

Let’s stick with the simple example of 3 edit boxes bound to my TPerson, via a\u00a0TObjectBindSourceAdapter<TPerson>. We also want a TBindNavigator connected to the TAdapterBindSource.<\/p>\n

If you run the app and start editing a value in the edit box, you’ll notice the Navigator\u00a0changes\u00a0state.<\/p>\n

\"\"<\/a>

Our Adapter in Edit mode. Note the Post and Cancel buttons are enabled?<\/p><\/div>\n

The Edit button becomes disabled, and the Post and Cancel buttons become enabled. A bit like a Dataset, right?<\/p>\n

In fact, this is the key analogy to use when you are thinking of Adapters: think of them like Datasets.<\/p><\/blockquote>\n

In fact, this is the key analogy to use when you are thinking of Adapters: think of them like Datasets. If you have a look at the methods and properties exposed on the adapters, you’ll spot many that are similar or exactly the same as TDataset, eg:<\/p>\n