Overview

This page introduces the basic concepts and common classes for all key functions and their view controllers in the iOS version of Global IM UIKit.

Design Patterns

In Global IM UIKit, the main functionalities are aggregated into two major pages:

• Conversation List Page: Adopts the MVVM code architecture:

  • Model Layer: RCChatModel is a wrapper for RCConversation in the IMLibCore SDK.
  • View Layer: RCChatListViewController view controller, divided into UI components such as RCChatListHeaderView and RCChatListView.
  • ViewModel Layer: RCChatListViewModel provides interface calls and callbacks related to conversation data, including loading, deleting, pinning, and marking as read.

• Conversation Page: Adopts the MVVM code architecture:

  • Model: RCMessageModel is a wrapper for RCMessage in IMLibCore.
  • View: RCChatViewController is divided into components such as RCChatHeaderView, RCMessageListView, and RCInputBar.
  • ViewModel: RCChatViewModel provides interface calls and callbacks related to conversation message data, including loading, deleting, and updating messages.

In addition, there are many derivative pages: multimedia, preview, user list, user information, etc.

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View Controllers

Name	View Controller
Conversation List	RChatListViewController
Conversation Page	RCChatViewController

Customization

If you do not want to use the default view controllers provided by Global IM UIKit, you can inherit from Global IM UIKit's view controllers to create a custom view controller class.

For example, you can refer to the following sample code to create a custom conversation list that inherits from RCChatListViewController and display the initialized instance via UINavigationController:

{
    // Conversation list display type, using one-to-one and group chat as an example
    RCChatType chatType = RCChatTypeSingle|RCChatTypeGroup;
    // Initialize the conversation list
    DemoChatListViewController *controller = [[DemoChatListViewController alloc] initWithChatType:chatType];
    // Must be displayed using UINavigationController
    [self.navigationController pushViewController:controller animated:YES];
    // If there is no external UINavigationController, create one
    // UINavigationController *navigationController = [[UINavigationController alloc] initWithRootViewController:controller];
    // navigationController.modalPresentationStyle = UIModalPresentationOverFullScreen;
    // navigationController.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
    // [self presentViewController:navigationController animated:YES completion:nil];
}

tip

The conversation list must have a navigation controller. If there is no controller, please refer to the code example to create one.

Lifecycle

The lifecycle methods of the view controllers are consistent with Apple's UIKit lifecycle methods. Global IM UIKit does not implement any custom lifecycle methods.

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UI Modules

In the design of Global IM UIKit, a "module" is an abstract concept. A module contains multiple components, known as module components. In the iOS version of Global IM UIKit, each view controller is integrated with a "module," corresponding to a page.

Module	Components
RCChatListViewController	- RCChatListHeaderView - RCChatListView
RCChatViewController	- RCChatHeaderView - RCMessageListView - RCInputBar

If you wish to use a custom view controller, you must override the viewDidLoad method of the view controller and add custom code after calling the parent class's viewDidLoad method.

Each module component has properties that use delegates and data sources to exchange view-related events and data with the view controller. To learn more about data flow and module customization, visit the Modules page.

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ViewModel

The ViewModel communicates directly with the IMLibCore SDK to exchange and request data. The view controller does not need to call IMLibCore SDK interfaces; it only needs to use the ViewModel in Global IM UIKit to manage and handle chat-related data.

Each ViewModel has a delegate that sends data updates as events to the view controller. The ViewModel also uses a data source to collect necessary data from the view controller.

All view controllers provided by Global IM UIKit have corresponding ViewModels. For example, RCChatListViewController, the class that displays the channel list view, has RCChatListViewModel.

Refer to the table below to see the view controller and ViewModel corresponding to each key function.

Function	View Controller	ViewModel	Delegate / Data Source
Conversation List	RCChatListViewController	RCChatListViewModel	- RCChatListViewModelDelegate - RCChatListViewModelDataSource
Conversation Page	RCChatViewController	RCChatViewModel	- RCChatViewModelDelegate - RCChatViewModelDataSource

Customization

If you want to customize existing events in the ViewModel, you can override the methods in the Delegate and DataSource. If the existing methods do not meet your needs, you can inherit from the Delegate and DataSource and provide them to Global IM UIKit.

You can visit the corresponding key function pages to learn how to customize the ViewModel for each key function.