Ionic is a popular framework for building cross-platform mobile and web applications using web technologies. One of the challenges of developing Ionic apps is managing state, which is the data and UI elements that change over time. In this article, you will learn how to manage state in Ionic using different approaches and tools.
State is the information that determines how your app behaves and looks at any given moment. For example, state can include user input, authentication status, network requests, navigation history, and UI components. Managing state well is important for creating a consistent, responsive, and user-friendly app. However, state can also become complex, unpredictable, and hard to debug if not handled properly.
State in app development refers to behaviour of the app component or any UI element like user inputs, displayed content, network updates, and device specifics. It's crucial because it: 1. Enhances user experience by aligning actions with expected outcomes. 2. Simplifies app design by connecting app components efficiently. 3. Facilitates testing by defining how the app should operate in different scenarios. Efficient state management ensures smooth functioning, making it a fundamental concept in app development. An example of a state in an app is like: 1: Updating shopping cart. 2: Start and play music on button press.
State is a piece of information that UI element (component) uses to determine when to rerender among other things. For example, whenever user adds item into the shopping cart, usually the number (usually shown as a badge) would increase in on the card icon, that number is a state, and the cart icon (UI component) uses that number to determine if it should rerender.
One of the simplest ways to manage state in Ionic is to use the built-in components that provide stateful functionality. For example, you can use ion-router to handle navigation and routing, ion-tabs to switch between views, ion-modal to display overlays, and ion-storage to persist data locally. These components use custom elements and web APIs to manage their own state and communicate with each other. You can access and modify their state using properties, methods, and events.
In app development, handling the state of an element or data is very important. Ionic which is a powerful framework, simplifies this with its components. 1. State Basics: It's an app's current status, controlled by Ionic components. 2. Ionic's State Tools: - Input Fields: Capture data and maintain state for forms. - Toggle Buttons: Manage choices effortlessly. - Tabs: Organize content and preserve state during navigation. 3. Ionic's Edge: These are the components that reduce manual state handling and offer consistency in-app behavior. Implementation of State in Ionic: Use Ionic's built-in state management features within each component. Leverage Ionic's event handling mechanisms to trigger state changes.
Another way to manage state in Ionic is to use Angular services, which are singleton objects that can store and share data across components. For example, you can use a service to store user data, preferences, settings, or any other global state. You can also use a service to encapsulate logic for fetching, updating, or deleting data from a backend. To use a service, you need to inject it into the components that need it using dependency injection. You can also use observables and RxJS operators to handle asynchronous and reactive state changes.
Angular provides it's full set of features allowing to build rich interfaces, it also has a very good integration with Ionic. In most of the cases Angular's Rxjs is used in order to manage asynchronous state that depends on the server (API data), and in case if global client state is needed it's a good practice to use Ngrx. There are also ways to handle global state manually, but most of the time it's not worth the effort of reinventing the bicycle.
NgRx is a library that implements the Redux pattern for managing state in Angular applications. Redux is a popular approach for managing complex and large-scale state using a single source of truth, immutable data, and pure functions. NgRx provides a set of tools and concepts to help you implement Redux in your Ionic app. For example, you can use actions to describe state changes, reducers to update state based on actions, selectors to access state from the store, effects to handle side effects, and devtools to debug state.
If you are using React as your UI library for Ionic, you can use Ionic React Hooks to manage state in your app. Ionic React Hooks are custom hooks that provide access to Ionic features and native APIs. For example, you can use useIonViewDidEnter and useIonViewDidLeave to manage the lifecycle of your components, useIonModal and useIonToast to display overlays, useIonRouter and useIonTabs to handle navigation and routing, and useStorage and useCamera to access native capabilities. You can also use the standard React hooks, such as useState and useEffect, to manage local and global state.
Ionic provides a good set of hooks to manage native functionality, however it's important to firstly understand the how React hooks work, specifically when it comes to managing the state. Hooks are essentially a cleaner way to access a set of features while using a functional components, this of an abstraction around certain logic that expose only relevant part to the components. Ionic React hook allow to gain native functionality, for example useWatchPosition hook is used to work with Geolocation API, the state could be manipulated depending on the values that are received from API.
MobX is another library that you can use to manage state in your Ionic React app. MobX is based on the principle of observable data, which means that any data that can change over time can be observed and reacted to by other parts of your app. MobX provides a simple and intuitive way to create and update observable data using decorators, actions, and computed values. You can also use MobX-react-lite to connect your components to your observable data using observer and useLocalStore. MobX can help you manage state with less boilerplate and more flexibility.
MobX is a simple, easy-to-use scalable, boilerplate-free state management solution. It allows us to control the application state outside of any UI framework like Flutter, to manage the app components independently. Mobx distinguishes the following concepts in an application. 1: State: tate in app development refers to behavior of the app component or any UI element like user inputs, displayed content, network updates, and device specifics 2: Actions: How the component behaves when the user triggers an event on it. 3: Derivations: The change that appears when the user triggers an event e.g. update cart quantity.
I would like to have a small example of managing the state with any state management provider just for letting to know how every developer writes code for managing the state. It could be a simple method that describe the thought process of developer