[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
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-(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] view
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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] view
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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] view
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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] view
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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] view
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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