我遇到了一个看起来非常复杂的自定义库，它对于任何想要内置消息传递系统的应用程序都非常有用。 JSQMessagesViewController on Github 。当我试图自己实现这个库时，我遇到了一些问题。一个我不太明白“协议(protocol)”和“类”的术语(我对类有一点了解)。第一个问题是我无法在 CollectionView 中使用 PFObjects，因为 JSQMessage 的实例需要通过大多数自定义方法传递。现在，我知道如何接收 PFObject 并从中获取属性
self.eachMessage = [self.messages objectAtIndex:indexPath.row]; //each message
self.eachMessage[@"message"] //message from the PFObject
self.eachMessage[@"sender"] //sender from the PFObject
JSQMessage 类具有表示 PFObject 属性的自定义属性，例如
JSQMessage *message = [[JSQMessage alloc] init]; //initialize it
message.senderId //could be the objectId of the user
message.senderDisplayName //the user's username
message.text //text of the message
message.date //time sent of the message
问题是，在自定义类 JSQMessage 中...所有这些属性都是只读的。我确信我可以进入并更改它，以便我可以将它们分配给我想要的东西，但这里一定有我遗漏的东西。我将在我的 .h 和 .m 文件中附加所有内容。 当我发送消息时 唯一通过的是文本，我相信这是因为它在来自 inputToolbar 上的 textView 时被接收。
.h 文件
#import <UIKit/UIKit.h>
#import <JSQMessagesViewController/JSQMessages.h>
#import <Parse/Parse.h>
#import <JSQMessagesViewController/JSQMessagesBubbleImageFactory.h>
@interface ConvoViewController : JSQMessagesViewController
@property (strong, nonatomic) NSMutableArray *messages;
@property (strong, nonatomic) PFUser *sender;
@property (strong, nonatomic) PFUser *receiver;
@property (strong, nonatomic) JSQMessage *eachMessage;
@property (strong, nonatomic) PFObject *aMessage;
@property (strong, nonatomic) JSQMessagesBubbleImageFactory *bubbleImage;
@end
.m 文件
- (void)viewDidLoad {
[super viewDidLoad];
//Color of the keyboard (Dark to match everything else)
self.inputToolbar.contentView.textView.keyboardAppearance = UIKeyboardAppearanceDark;
//Color the inputview background
self.inputToolbar.backgroundColor = [UIColor colorWithWhite:0 alpha:0.9];
//Delete the avatars appearing next to the messages
self.collectionView.collectionViewLayout.incomingAvatarViewSize = CGSizeZero;
self.collectionView.collectionViewLayout.outgoingAvatarViewSize = CGSizeZero;
//Set the senderID
self.senderId = self.sender.objectId;
}
- (void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:YES];
//Query for part of the messages
PFQuery *messages1 = [PFQuery queryWithClassName:@"Messages"];
[messages1 whereKey:@"sender" equalTo:self.sender];
[messages1 whereKey:@"receiver" equalTo:self.receiver];
//Query for other part of messages
PFQuery *messages2 = [PFQuery queryWithClassName:@"Messages"];
[messages2 whereKey:@"sender" equalTo:self.receiver];
[messages2 whereKey:@"receiver" equalTo:self.sender];
//Combine those queries
PFQuery *allMessages = [PFQuery orQueryWithSubqueries:@[messages1, messages2]];
[allMessages findObjectsInBackgroundWithBlock:^(NSArray *objects, NSError *error) {
self.messages = [objects mutableCopy];
[self.collectionView reloadData];
}];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#pragma mark - Send Button
- (void)didPressSendButton:(UIButton *)button withMessageText:(NSString *)text senderId:(NSString *)senderId senderDisplayName:(NSString *)senderDisplayName date:(NSDate *)date {
[JSQSystemSoundPlayer jsq_playMessageSentSound];
JSQMessage *message = [[JSQMessage alloc] initWithSenderId:self.sender.objectId
senderDisplayName:self.sender.username
date:[NSDate date]
text:text];
[self.messages addObject:message];
NSLog(@"%@", text);
[self finishSendingMessageAnimated:YES];
}
#pragma mark - JSQMessages Data Source methods
- (id<JSQMessageData>)collectionView:(JSQMessagesCollectionView *)collectionView messageDataForItemAtIndexPath:(NSIndexPath *)indexPath
{
//Return the actual message at each indexpath.row
return [self.messages objectAtIndex:indexPath.row];
}
- (id<JSQMessageBubbleImageDataSource>)collectionView:(JSQMessagesCollectionView *)collectionView messageBubbleImageDataForItemAtIndexPath:(NSIndexPath *)indexPath
{
/**
* You may return nil here if you do not want bubbles.
* In this case, you should set the background color of your collection view cell's textView.
*
* Otherwise, return your previously created bubble image data objects.
*/
JSQMessage *message = [self.messages objectAtIndex:indexPath.item];
if ([message.senderId isEqualToString:self.senderId]) {
return [self.bubbleImage incomingMessagesBubbleImageWithColor:[UIColor orangeColor]];
}
return [self.bubbleImage outgoingMessagesBubbleImageWithColor:[UIColor grayColor]];
}
#pragma mark - Collection View
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {
//Number of messages
return self.messages.count;
}
- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView {
//Number of sections
return 1;
}
- (UICollectionViewCell *)collectionView:(JSQMessagesCollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {
//Creating or initial cell for the number of index paths (number of messages)
JSQMessagesCollectionViewCell *cell = (JSQMessagesCollectionViewCell *)[super collectionView:collectionView cellForItemAtIndexPath:indexPath];
//Put our messages dictionaries into PFObject so we can put them into individual cells
self.eachMessage = [self.messages objectAtIndex:indexPath.row];
//Put the message object into the textView's text property
cell.textView.text = self.eachMessage.text;
//Setting the text color of the message bubble based upon the sender
if ([self.eachMessage.senderId isEqualToString:self.senderId]) {
cell.textView.textColor = [UIColor blackColor];
} else {
cell.textView.textColor = [UIColor whiteColor];
}
//Set the top label to the person who sent the message
cell.cellTopLabel.text = [NSString stringWithFormat:@"@%@", self.eachMessage.senderId];
//Format the bottom label to a readable date
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"MM/dd/yy h:mm a"];
cell.cellBottomLabel.text = [dateFormatter stringFromDate:self.eachMessage.date];
//If there is a link of some sorts in the message
cell.textView.linkTextAttributes = @{ NSForegroundColorAttributeName : cell.textView.textColor,
NSUnderlineStyleAttributeName : @(NSUnderlineStyleSingle | NSUnderlinePatternSolid) };
//What we return into the collectionview
return cell;
}
最佳答案
这是我的代码的一部分。整个文件很大，如果我分享这些文件，我的老板不会高兴。 :-)
这是我如何在我的 DemoMessagesViewController 中加载我的 DemoData :
self.demoData = [[DemoModelData alloc] init];
self.demoData.users = @{self.senderId:self.senderDisplayName,
self.targetUserId:self.targetUserName};
UIImage *tempImg = [HTTPServerKaDost fetchImageFromUrlString:userProfile.profilePicUrl]; //replace with your code to load image
JSQMessagesAvatarImage *srcImage = [JSQMessagesAvatarImageFactory
avatarImageWithImage:tempImg
diameter:kJSQMessagesCollectionViewAvatarSizeDefault];
tempImg = [HTTPServerKaDost fetchImageFromUrlString:self.targetUserImageFullUrl];
JSQMessagesAvatarImage *destImage = [JSQMessagesAvatarImageFactory
avatarImageWithImage:tempImg
diameter:kJSQMessagesCollectionViewAvatarSizeDefault];
self.demoData.avatars = @{self.senderId:srcImage,
self.targetUserId:destImage};
[self.demoData loadMessages];
在
loadMessages 方法中(由我在 DemoModelData 类中添加)，创建 JSQMessage 对象:JSQMessage *msg = [[JSQMessage alloc] initWithSenderId:[msgDict valueForKey:@"sender"]
senderDisplayName:[msgDict valueForKey:@"fname"]
date:dateT
text:[msgDict valueForKey:@"data"]];
[self.messages addObject:msg];
任何时候你想刷新聊天 View ，在
DemoMessagesViewController 中调用它:[self finishReceivingMessageAnimated:YES];
[self scrollToBottomAnimated:YES];
关于ios - 在 Parse.com 中使用 JSQMessagesViewController，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/28484821/