[iPhone高级]基于XMPP的iOS聊天客户端程序(iOS端三)

前两篇介绍了如何通过XMPP来发送消息和接收消息，这一篇我们主要介绍如何来美化我们的聊天程序，看一下最终效果呢，当然源程序也会在最后放出



好了，我们来看一下我们写的程序

这里我们自定义了TableViewCell



一行是显示发布日期，一行是显示发送的消息，还有一个是背景

[java]
view plaincopy

-(id)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier{

self = [super initWithStyle:style reuseIdentifier:reuseIdentifier];
if (self) {
//日期标签
senderAndTimeLabel = [[UILabel alloc] initWithFrame:CGRectMake(10, 5, 300, 20)];
//居中显示
senderAndTimeLabel.textAlignment = UITextAlignmentCenter;
senderAndTimeLabel.font = [UIFont systemFontOfSize:11.0];
//文字颜色
senderAndTimeLabel.textColor = [UIColor lightGrayColor];
[self.contentView addSubview:senderAndTimeLabel];

//背景图
bgImageView = [[UIImageView alloc] initWithFrame:CGRectZero];
[self.contentView addSubview:bgImageView];

//聊天信息
messageContentView = [[UITextView alloc] init];
messageContentView.backgroundColor = [UIColor clearColor];
//不可编辑
messageContentView.editable = NO;
messageContentView.scrollEnabled = NO;
[messageContentView sizeToFit];
[self.contentView addSubview:messageContentView];

}

return self;

}

定义好，在UITableViewCell中将Cell改成我们自己定义的Cell

[java]
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-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{

static NSString *identifier = @"msgCell";

KKMessageCell *cell =(KKMessageCell *)[tableView dequeueReusableCellWithIdentifier:identifier];

if (cell == nil) {
cell = [[KKMessageCell alloc] initWithStyle:UITableViewCellStyleValue1 reuseIdentifier:identifier];
}

NSMutableDictionary *dict = [messages objectAtIndex:indexPath.row];

//发送者
NSString *sender = [dict objectForKey:@"sender"];
//消息
NSString *message = [dict objectForKey:@"msg"];
//时间
NSString *time = [dict objectForKey:@"time"];

CGSize textSize = {260.0 ,10000.0};
CGSize size = [message sizeWithFont:[UIFont boldSystemFontOfSize:13] constrainedToSize:textSize lineBreakMode:UILineBreakModeWordWrap];

size.width +=(padding/2);

cell.messageContentView.text = message;
cell.accessoryType = UITableViewCellAccessoryNone;
cell.userInteractionEnabled = NO;

UIImage *bgImage = nil;

//发送消息
if ([sender isEqualToString:@"you"]) {
//背景图
bgImage = [[UIImage imageNamed:@"BlueBubble2.png"] stretchableImageWithLeftCapWidth:20 topCapHeight:15];
[cell.messageContentView setFrame:CGRectMake(padding, padding*2, size.width, size.height)];

[cell.bgImageView setFrame:CGRectMake(cell.messageContentView.frame.origin.x - padding/2, cell.messageContentView.frame.origin.y - padding/2, size.width + padding, size.height + padding)];
}else {

bgImage = [[UIImage imageNamed:@"GreenBubble2.png"] stretchableImageWithLeftCapWidth:14 topCapHeight:15];

[cell.messageContentView setFrame:CGRectMake(320-size.width - padding, padding*2, size.width, size.height)];
[cell.bgImageView setFrame:CGRectMake(cell.messageContentView.frame.origin.x - padding/2, cell.messageContentView.frame.origin.y - padding/2, size.width + padding, size.height + padding)];
}

cell.bgImageView.image = bgImage;
cell.senderAndTimeLabel.text = [NSString stringWithFormat:@"%@ %@", sender, time];

return cell;

}

在这个Cell里设置了发送的消息的背景图和接收消息的背景图
这里在字典里有一个"time"

这是我们接收和发送消息的时间

[java]
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+(NSString *)getCurrentTime{

NSDate *nowUTC = [NSDate date];

NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setTimeZone:[NSTimeZone localTimeZone]];
[dateFormatter setDateStyle:NSDateFormatterMediumStyle];
[dateFormatter setTimeStyle:NSDateFormatterMediumStyle];

return [dateFormatter stringFromDate:nowUTC];

}

在AppDelegate.m中
将我们收到消息的内容也做一下调整

[java]
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- (void)xmppStream:(XMPPStream *)sender didReceiveMessage:(XMPPMessage *)message{

// ......

NSMutableDictionary *dict = [NSMutableDictionary dictionary];
[dict setObject:msg forKey:@"msg"];
[dict setObject:from forKey:@"sender"];
//消息接收到的时间
[dict setObject:[Statics getCurrentTime] forKey:@"time"];

......

}

最后我们再设置一下每一行显示的高度

[java]
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//每一行的高度
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{

NSMutableDictionary *dict = [messages objectAtIndex:indexPath.row];
NSString *msg = [dict objectForKey:@"msg"];

CGSize textSize = {260.0 , 10000.0};
CGSize size = [msg sizeWithFont:[UIFont boldSystemFontOfSize:13] constrainedToSize:textSize lineBreakMode:UILineBreakModeWordWrap];

size.height += padding*2;

CGFloat height = size.height < 65 ? 65 : size.height;

return height;

}

，对了，在发送消息的时候，别忘了也加上

[java]
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- (IBAction)sendButton:(id)sender {

//本地输入框中的信息
......

if (message.length > 0) {

.....

NSMutableDictionary *dictionary = [NSMutableDictionary dictionary];

[dictionary setObject:message forKey:@"msg"];
[dictionary setObject:@"you" forKey:@"sender"];
[dictionary setObject:[Statics getCurrentTime] forKey:@"time"];

[messages addObject:dictionary];

//重新刷新tableView
[self.tView reloadData];

}

}

好了，这里关于XMPP发送消息的教程就结束了，以后我们会详细介绍其他关于XMPP的内容源码下载