| // Copyright 2015 The Vanadium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| /** |
| * These classes provide bindings between Android widgets and Syncbase data. Most functionality is |
| * most easily accessed through access vectors in {@link io.v.baku.toolkit} rather than |
| * instantiating directly from this package. Otherwise, it is easiest to instantiate a |
| * `new {@link io.v.baku.toolkit.bind.BindingBuilder}()` and chain methods to configure bindings. |
| * |
| * For the reasons outlined in {@link io.v.rx.syncbase}, Vanadium state distribution with Syncbase |
| * would ideally be done with pure FRP [MVVM] |
| * (https://en.wikipedia.org/wiki/Model%E2%80%93view%E2%80%93viewmodel), with distributed state |
| * elements modeled in Syncbase. |
| * |
| *  |
| * |
| * **Fig: Ideal MVVM for distributed apps** |
| * |
| * However, while this is easily accomplished with [Flutter](https://flutter.io/), the Baku Toolkit |
| * would need to implement an Android viewmodel layer to achieve the same for Android Java, which |
| * starts to amount to reimplementing Flutter for Java. Instead, the Baku Android Toolkit offers |
| * data bindings that allow Syncbase to drive more conventional Android Java UI widgets, and to |
| * allow those widgets to update distributed state in Syncbase. |
| * |
| *  |
| * |
| * **Fig: Baku data bindings without viewmodel** |
| * |
| * Even though these data bindings are not true MVVM, app developers are encouraged to treat them |
| * declaratively, and to make use of pure functional transformations wherever possible to simplify |
| * their code. Imperative code is however still useful for Android initialization, implementing |
| * reactive widget update logic, and writing to Syncbase. |
| * |
| * Data bindings are offered to client applications via builders. Many facets of bindings are |
| * derived from their usage context. For example, `bindTo(...)` methods perform type introspection |
| * to construct appropriate binding types for the widget being bound (and possibly the row type |
| * being bound to). In the future, we may add a plug-in to preprocess Android layout markup similar |
| * to the [Android Data Binding Library] |
| * (http://developer.android.com/tools/data-binding/guide.html). |
| * |
| * At present, for simplicity, each data binding that reads from Syncbase has its own Syncbase watch |
| * stream. If this ends up wasting resources and degrading performance, we can optimize to minimize |
| * the number of watch streams and broadcast filtered streams to each data binding. |
| * |
| * Offering data bindings rather than pure functional MVVM transforms does introduce some |
| * coordination concerns between read and write bindings. Strategies for dealing with coordination |
| * are included in the toolkit. |
| */ |
| package io.v.baku.toolkit.bind; |
