iOS开发（环信及时通讯）-获取聊天记录

之前公司集成环信聊天SDK,在聊天室开发开发过程中历史聊天记录获取卡了一点时间，现在将历史聊天记录的开发方法简单的记录一下，分享给大家

第一步：服务端获取环信聊天记录，提供接口返回数据

第二步：前端做消息类型判断，做处理

尽量将代码修改的很通俗易懂，大神不要喷，简单的东西容易理解，也是摸索中总结出来的

一：

服务端提供的查询接口，需要提供一些参数，以我的项目为例，有三个参，最重要的是一个分页字符，初次提供为一个空的字符串

所以在viewDidLoad 里的赋予一个记录分页的字符串为空值，

记录：cursorStr = @"";

请求：[self getInfoMoreMeassageRquest];

请求后，服务端返回的json数据大致如下：

{

action = get;

count = 50;

cursor = MTYxOTcyOTYyNTpnR2tBQVFNQWdHa0FCZ0ZUOU1SOWF3Q0FkUUFRVHg5dzZ2MWJFZVd2Rk9NRXJhdmxCQUNBZFFBUVR4OXc0UDFiRWVXMVBSR1FSeERuOXdB;

duration = 3990;

entities =    (

{

"chat_type" = groupchat;

created = 1460513153714;

from = 100000013;

groupId = 135220650137616892;

modified = 1460513153714;

"msg_id" = 184461770679649224;

payload =            {

bodies =                (

{

msg = "\U5fae\U7b11\U30fb\U00b0\U9633\U5149\U52a0\U5165\U804a\U5929\U5ba4";

type = txt;

}

);

ext =                {

"dasgang_type" = 0;

friendHeaderImage = "";

headurl = "http://chenggua.com/imagesUrl/20160407/201604070957593310.png";

"is_dashang" = 0;

"is_join_notice" = 1;

nickName = "\U5fae\U7b11\U30fb\U00b0\U9633\U5149";

roleName = "\U4f1a\U957f";

sex = 1;

userid = 100000013;

wealthGrade = 1;

};

};

timestamp = 1460513152817;

to = 135220650137616892;

type = chatmessage;

uuid = "40ac892a-011c-11e6-b8d6-89c365e78de2";

},

params =    {

cursor =        (

""

);

limit =        (

50

);

ql =        (

"select * where to='135220650137616892' order by timestamp desc "

);

};

path = "/chatmessages";

timestamp = 1460518366731;

uri = "http://a1.easemob.com/daowen/chenggua/chatmessages";

}

可以看到返回的数据里包含一个cursor = MTYxOTcyOTYyNTpnR2tBQVFNQWdHa0FCZ0ZUOU1SOWF3Q0FkUUFRVHg5dzZ2MWJFZVd2Rk9NRXJhdmxCQUNBZFFBUVR4OXc0UDFiRWVXMVBSR1FSeERuOXdB;

这个分页就是再次下拉的时候，加载第二页数据的时候需要提交到服务端请求

所以在请求中将此字符串赋值给 之前定义的记录字符串

cursorStr=jsonData[@"cursor"];

需要注意的是，如果聊天记录加载完毕之后，cursor会返回为空，所以在slimeRefresh delegate做了一下判断

if (_conversationType == eConversationTypeChatRoom){//这里我是判断聊天室才要历史记录，单聊不需要，可以忽略不管

if ([self isBlankString:cursorStr]) {//这个方法是判断是否为空

[_slimeView endRefresh];

return;

}else{

[self getInfoMoreMeassageRquest];

}

-----------------判断字符窜是否为空的方法

- (BOOL) isBlankString:(NSString *)string {

if (string == nil || string == NULL) {

return YES;

}

if ([string isKindOfClass:[NSNull class]]) {

return YES;

}

if ([[string stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]] length]==0) {

return YES;

}

return NO;

}

以上就是请求历史聊天记录部分

二：根据返回数据的消息类型做处理

简单的说就是根据不同的消息类型构建消息，然后插入到数据库就好了，直接上代码，我做了四中消息类型的判断，是可以直接复制拿去用的，：纯文字、图片、录音、地图位置

cursorStr=jsonData[@"cursor"];

NSMutableArray * arr=jsonData[@"entities"];

for (NSDictionary * dicc in arr) {

NSArray * xiaoxiArr = [NSArray arrayWithArray:dicc [@"payload"][@"bodies"]];

if ([[xiaoxiArr lastObject][@"type"]isEqualToString:@"txt"]) {//纯文字

EMChatText *chatText = [[EMChatText alloc] initWithText:[xiaoxiArr lastObject][@"msg"]];

EMTextMessageBody *textBody = [[EMTextMessageBody alloc] initWithChatObject:chatText];

EMMessage * message = [[EMMessage alloc]initMessageWithID:dicc[@"msg_id"] sender:dicc[@"from"] receiver:_conversation.chatter bodies:@[textBody]];

message.isRead = YES;

message.deliveryState = eMessageDeliveryState_Delivered;

message.ext = dicc [@"payload"][@"ext"];

message.messageType = eMessageTypeChatRoom;

message.timestamp = [dicc [@"timestamp"] longLongValue];

[[EaseMob sharedInstance].chatManager insertMessageToDB:message append2Chat:YES];

}else if ([[xiaoxiArr lastObject][@"type"]isEqualToString:@"img"]){//图片

NSDictionary * diccSize = [xiaoxiArr lastObject][@"size"];

NSDictionary *imageDic = @{EMMessageBodyAttrKeySecret:[xiaoxiArr lastObject][@"secret"],

EMMessageBodyAttrKeySize:@{EMMessageBodyAttrKeySizeWidth:[NSNumber numberWithFloat:[diccSize[@"width"] floatValue]],EMMessageBodyAttrKeySizeHeight:[NSNumber numberWithFloat:[diccSize[@"height"] floatValue]]},

EMMessageBodyAttrKeyFileName:@"image.jpg",

EMMessageBodyAttrKeyType:EMMessageBodyAttrTypeImag,

EMMessageBodyAttrKeyUrl:[xiaoxiArr lastObject][@"url"],

EMMessageBodyAttrKeyFileLength:[NSNumber numberWithInteger:[[xiaoxiArr lastObject][@"file_length"] integerValue]]};

EMImageMessageBody *imageBody = [EMImageMessageBody imageMessageBodyFromBodyDict:imageDic forChatter:_chatter];

EMMessage * image = [[EMMessage alloc]initMessageWithID:dicc[@"msg_id"] sender:dicc[@"from"] receiver:_conversation.chatter bodies:@[imageBody]];

image.timestamp = [dicc [@"timestamp"] longLongValue];

image.isReadAcked = YES;

image.messageType = eMessageTypeChatRoom;

image.deliveryState = eMessageDeliveryState_Delivered;

image.isRead = YES;

image.ext = dicc [@"payload"][@"ext"];

[[EaseMob sharedInstance].chatManager insertMessageToDB:image append2Chat:YES];

}else if ([[xiaoxiArr lastObject][@"type"]isEqualToString:@"audio"]){//音频

NSDictionary *voiceDic = @{EMMessageBodyAttrKeySecret:[xiaoxiArr lastObject][@"secret"],

EMMessageBodyAttrKeyFileName:[xiaoxiArr lastObject][@"filename"],

EMMessageBodyAttrKeyDuration:[NSNumber numberWithInteger:[[xiaoxiArr lastObject][@"length"] integerValue]],

EMMessageBodyAttrKeyType:EMMessageBodyAttrTypeAudio,

EMMessageBodyAttrKeyUrl:[xiaoxiArr lastObject][@"url"],

EMMessageBodyAttrKeyFileLength:@8870};

EMVoiceMessageBody *voiceBody = [EMVoiceMessageBody voiceMessageBodyFromBodyDict:voiceDic forChatter:_chatter];

EMMessage *voice = [[EMMessage alloc] initMessageWithID:dicc[@"msg_id"] sender:dicc[@"from"] receiver:_conversation.chatter bodies:@[voiceBody]];

voice.timestamp = [dicc [@"timestamp"] longLongValue];

voice.isReadAcked = YES;

voice.deliveryState = eMessageDeliveryState_Delivered;

voice.isRead = YES;

voice.ext = dicc [@"payload"][@"ext"];

voice.messageType = eMessageTypeChatRoom;

[[EaseMob sharedInstance].chatManager insertMessageToDB:voice append2Chat:YES];

}

else if ([[xiaoxiArr lastObject][@"type"]isEqualToString:@"loc"]){//地理位置

EMChatLocation * location  = [[EMChatLocation alloc]initWithLatitude:[[xiaoxiArr lastObject][@"lat"] doubleValue] longitude:[[xiaoxiArr lastObject][@"lng"] doubleValue] address:[xiaoxiArr lastObject][@"addr"]];

EMLocationMessageBody * locBodiy = [[EMLocationMessageBody alloc]initWithChatObject:location];

EMMessage * loocc = [[EMMessage alloc]initMessageWithID:dicc[@"msg_id"] sender:dicc[@"from"] receiver:_conversation.chatter bodies:@[locBodiy]];

loocc.timestamp = [dicc [@"timestamp"] longLongValue];

loocc.isReadAcked = YES;

loocc.ext = dicc [@"payload"][@"ext"];

loocc.isRead = YES;

loocc.messageType = eMessageTypeChatRoom;

[[EaseMob sharedInstance].chatManager insertMessageToDB:loocc append2Chat:YES];

}

}

简单的小需求，对于第一次做环信的小白来说应该有些帮助，堆字水平不咋地，还希望大家多多沟通，共同交流