tencent cloud

// Original message object in the conversation
V2TIMMessage *originMessage; 
// Modify the `cloudCustomData` information of the message object
originMessage.cloudCustomData = [@"modify_cloud_custom_data" dataUsingEncoding:NSUTF8StringEncoding];
// If the message is a text message, modify the text message content
if (V2TIM_ELEM_TYPE_TEXT == originMessage.elemType) {
    originMessage.textElem.text = @"modify_text";
}
[[V2TIMManager sharedInstance] modifyMessage:originMessage completion:^(int code, NSString *desc, V2TIMMessage *msg) {
    // After the message is modified, `msg` is the modified message object.
}];

template <class T>
class CompleteCallback final : public V2TIMCompleteCallback<T> {
public:
    using InternalCompleteCallback =
        std::function<void(int, const V2TIMString&, const T&)>;

    CompleteCallback() = default;
    ~CompleteCallback() override = default;

    void SetCallback(InternalCompleteCallback complete_callback) { complete_callback_ = std::move(complete_callback); }

    void OnComplete(int error_code, const V2TIMString& error_message, const T& value) override {
        if (complete_callback_) {
            complete_callback_(error_code, error_message, value);
        }
    }

private:
    InternalCompleteCallback complete_callback_;
};

// V2TIMMessage originMessage;
std::string str = u8"modify_cloud_custom_data";
// Modify the `cloudCustomData` information of the message object
originMessage.cloudCustomData = {reinterpret_cast<const uint8_t*>(str.data()), str.size()};
if (originMessage.elemList.Size() == 1) {
    V2TIMElem* elem = originMessage.elemList[0];
    if (elem->elemType == V2TIMElemType::V2TIM_ELEM_TYPE_TEXT) {
        // If the message is a text message, modify the text message content
        auto textElem = static_cast<V2TIMTextElem*>(elem);
        textElem->text = "modify_text";
    }
}

auto callback = new CompleteCallback<V2TIMMessage>{};
callback->SetCallback([=](int error_code, const V2TIMString& error_message, const V2TIMMessage& message) {
    // After the message is modified, `message` is the modified message object.
    delete callback;
});

V2TIMManager::GetInstance()->GetMessageManager()->ModifyMessage(originMessage, callback);

// Add a message listener
[[V2TIMManager sharedInstance] addAdvancedMsgListener:self];
/// Notification of the message content modification
- (void)onRecvMessageModified:(V2TIMMessage *)msg {
    // `msg` is the modified message object.
}

class AdvancedMsgListener final : public V2TIMAdvancedMsgListener {
public:
    // Notification of the message content modification
    void OnRecvNewMessage(const V2TIMMessage& message) override {
        // `message` is the modified message object.
    }
    // Other members ...
};

// Note that `advancedMsgListener` should not be released before the IM SDK is uninitialized,
// otherwise the message callback cannot be called.
AdvancedMsgListener advancedMsgListener;
V2TIMManager::GetInstance()->GetMessageManager()->AddAdvancedMsgListener(&advancedMsgListener);