Chapter Summary

Summarizing adaptive UI and networking in GetX

In this chapter on responsiveness and networking with GetX, we explored how to create adaptive layouts, handle networking tasks, and configure network behavior. Through widgets like GetResponsiveView, developers can easily craft layouts for different screen sizes. GetConnect streamlines communication with APIs and WebSockets, while its configuration options allow fine-tuning of networking behavior. In this summary lesson, we’ll revisit the fundamental concepts covered in this chapter’s lessons. So, let’s review each lesson one by one.

Responsive widgets and screen utilities

• Overview:

  • GetX facilitates responsive layout design with specialized widgets and utilities, ensuring optimal user experiences across diverse devices and screen sizes.

• One widget, multiple layouts:

  • GetResponsiveView empowers developers to create different layouts for desktops, tablets, phones, and watches within a single class, enhancing adaptability and scalability.

• Specifying the default layout:

  • The builder() method serves as the default layout renderer, ensuring consistent UI rendering across all screen sizes, with the option to enforce its usage using alwaysUseBuilder.

• Accessing screen information:

  • The ResponsiveScreen class provides developers essential screen information regarding screen dimensions and types. This allows us to create flexible UIs for different screens, enhancing responsiveness and user interaction.

• Screen settings customization:

  • Fine-tuning responsive behavior is achievable through the ResponsiveScreenSettings class, allowing developers to define custom breakpoints.

HTTP requests

• Introduction to GetConnect:

  • GetConnect is GetX’s built-in networking library, facilitating HTTP requests over REST and GraphQL protocols with extensive configuration options and advanced features.

• REST API:

  • HTTP methods:

    • GET method: Retrieves data from the server.

    • POST method: Adds a new entry to the database.

    • PUT method: Updates existing data on the server.

    • DELETE method: Deletes a data entry from the server database.

    • PATCH method: Partially modifies data on the server without replacing the entire entry.

  • Request the metadata:

    • Headers, content types, and queries can be passed to all methods, providing additional information and filtering options.

  • Upload progress tracking:

    • Track upload progress with the uploadProgress parameter, facilitating UI updates during large data uploads.

  • Custom decoding:

    • Define custom decoders for response data within the request method, allowing tailored data processing.

  • Response:

    • The Response class object contains request status information and response data, providing access to the status code, headers, and body.

• GraphQL:

  • Query syntax:

    • GraphQL query structure allows fetching specific fields of data from the server.

  • Mutation syntax:

    • Used to modify data, such as adding, updating, or deleting entries in the database.

  • Making a request:

    • Use the query method in GetConnect to send GraphQL queries or mutations.

    • Specify the query or mutation strings and the URL for the GraphQL API endpoint.

WebSockets

• What are WebSockets?

  • WebSockets facilitate simultaneous two-way communication between the client and the server, enabling real-time interaction in applications like chatting apps and multiplayer games.

• Establishing a connection:

  • Create an instance of GetConnect to manage WebSocket connections.

  • Use GetConnect's socket method to create a GetSocket instance with the server URL.

  • Connect to the socket using the connect method.

• Listeners:

  • onOpen: Triggered upon connection establishment.

  • onMessage: Called for each new message received.

  • on: Listens to specific events categorized by name.

  • onClose: Triggers when the connection closes.

  • onError: Triggered upon encountering an error in the connection.

• Messages and events:

  • Use the send method to pass messages over the connection.

  • Emit events with the emit method, specifying event names and associated data.

• Closing the connection:

  • Close the socket using the close method for temporary disconnection.

  • Permanently close the socket with the dispose method.

• Additional configuration:

  • Specify whether to allow self-signed certificates.

  • Set the ping duration to check connection health at regular intervals.

Configuration

• Extending GetConnect:

  • We can extend the GetConnect class to conveniently place server call methods within the class itself, improving code organization.

• Base URL:

  • Setting a base URL allows us to avoid specifying the same URL in every request by automatically appending it to all requests.

• Content type:

  • We can set a default content type for requests, which can be overridden in specific requests.

• Decoder:

  • The default decoder can be overridden to deserialize response data into custom model structures.

• User agent:

  • Customization of the user agent string sent with each request, including whether to send it or not, is possible.

• Certificates:

  • Options are available to allow auto-signed certificates and load trusted certificates.

• Credentials:

  • For Flutter Web apps, credentials like cookies can be supplemented with requests.

• Redirects:

  • Control over whether to allow redirects and how many redirects can occur is provided.

• Proxy:

  • Support for setting up a proxy to make requests from a different host is available.

• Time-out:

  • Setting the duration after which a request stops expecting a response.

• Request modifier:

  • A request modifier intercepts and modifies requests before they are sent.

• Response modifier:

  • A response modifier intercepts and modifies responses before they reach the app.

• Authenticator:

  • An authenticator is a special request modifier that handles authentication logic before general modifiers.

  • We can specify the number of attempts it makes before failing the request.