Models

A model in the Model View Controller concept holds the data and provides methods to retrieve the data from the database and to set and update data.

SAPUI5 provides the following predefined models:

• The JSON model can be used to bind controls to JavaScript object data, which is usually serialized in the JSON format. The JSON model is a client-side model and, therefore, intended for small datasets, which are completely available on the client. The JSON model supports two-way binding.
• The XML model is a client-side model intended for small datasets, which are completely available on the client. The XMLModel does not contain mechanisms for server-based paging or loading of deltas
• The Resource model is designed to handle data in resource bundles, mainly to provide texts in different languages.
• The OData model enables binding of controls to data from OData services. The OData model is a server-side model: the dataset is only available on the server and the client only knows the currently visible rows and fields. This also means that sorting and filtering on the client is not possible. For this, the client has to send a request to the server. The OData model currently supports OData version 2.0.

The JSON model, XML model, and the resource model are client-side models, meaning that the model data is loaded completely and is available on the client. Operations such as sorting and filtering are executed on the client without further server requests. The OData model is a server-side model and only loads the data requested by the user interface from the server. Any changes in data binding or list operations require a new request to the server.

You can not only define one model for your applications, but define different areas in your application with different models and assign single controls to a model. You can also define nested models, for example, a JSON model defined for the application and an OData model for a table control contained in the application.

A web application should support several data sources, such as JSON, XML, Atom, or OData. However, the way in which data binding is defined and implemented within the UI controls should be independent of the respective data source. It is also possible to create a custom model implementation for data sources that are not yet covered by the framework or are domain-specific.