How to add a text to a File Message in a Group Channel

[lookdeceline]

Question

How to create a custom File Message cell that displays text sent with an image?

Answer

1. Register your custom custom File Message cell that subclasses SBUFileMessageCell.

class MyGroupChannelModuleList: SBUGroupChannelModule.List {
    override func setupViews() {
        self.register(fileMessageCell: MyFileMessageCell())

        // make sure to call super.setupViews()
        super.setupViews()
    }
}

2. Implement your custom SBUFileMessageCell.

class MyFileMessageCell: SBUFileMessageCell {
    lazy var myLabel: UILabel = {
        let label = UILabel()
        label.backgroundColor = .systemYellow
        label.textColor = .black
        label.font = .systemFont(ofSize: 14)
        label.numberOfLines = 0
        label.textAlignment = self.position == .left ? .left : .right
        label.setContentHuggingPriority(.init(100), for: .horizontal)
        return label
    }()
    
    override func configure(with configuration: SBUBaseMessageCellParams) {
        // make sure to call super.configure()
        super.configure(with: configuration)
        
        guard let configuration = configuration as? SBUFileMessageCellParams else { return }
        guard let message = configuration.fileMessage else { return }
        
        // adds the custom UILabel only when the content of file is image or video.
        // adjust the conditions according to your needs.
        switch SBUUtils.getFileType(by: message) {
        case .image, .video:
            myLabel.text = message.data.isEmpty ? "no data in the message" : message.data
            self.mainContainerView.insertArrangedSubview(self.myLabel, at: 0)
        default:
            for subview in self.mainContainerView.stackView.subviews {
                if subview is UILabel {
                    subview.removeFromSuperview()
                }
            }
        }
    }
}

3. Assign your custom GroupChannelModuleList before it is presented. A good place to do so is AppDelegate.

// AppDelegate.swift 
SBUModuleSet.GroupChannelModule.ListComponent = MyGroupChannelModuleList.self

Result