顯示iOS徽章編號/處理未讀消息（xCode-OBJECTIVE-C）

Question

我想更新收件箱標志以顯示未讀消息的數量（我的消息不會自毀，應用程序類似於iOS消息）。

當用戶單擊消息並返回到“收件箱”選項卡時，徽章應進行更新。 另外，我想標記未讀單元格的背景顏色與已讀單元格的不同...這樣用戶可以知道已讀和未讀的內容。

我有一些工作代碼，但現在我得到：

“警告：正在主線程上執行長時間運行的操作。中斷warnBlockingOperationOnMainThread（）進行調試。”

這是我用於更新未讀消息的代碼：

PFQuery *query = [PFQuery queryWithClassName:@"Messages"];
    [query whereKey:@"recipientIds" equalTo:[[PFUser currentUser] objectId]];
    [query orderByDescending:@"createdAt"];
    [query findObjectsInBackgroundWithBlock:^(NSArray *objects, NSError *error) {
        if (error) {
            NSLog(@"Error: %@ %@", error, [error userInfo]);
        } else {
            // messages were found!
            self.messages = objects;

            //find unread messages
            [query whereKey:@"readBy" notEqualTo:[[PFUser currentUser] objectId]];
            self.unreadMessages = [query findObjects];

            // set badge # to number of msgs
            if (self.unreadMessages.count > 0) {

                [[self navigationController] tabBarItem].badgeValue = [NSString stringWithFormat:@"%lu", (unsigned long)self.unreadMessages.count];
            }

            [self.tableView reloadData];

用於更新單元格的代碼：

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"Cell" forIndexPath:indexPath];

PFObject *message = [self.messages objectAtIndex:indexPath.row];
cell.textLabel.text = [message objectForKey:@"senderEmail"];

if ([self.unreadMessages containsObject:message]) {
    // color background gray, bold the font
}else{
   // leave cell alone
}

Answer 1

[query findObjectsInBackgroundWithBlock:^(NSArray *objects, NSError *error)  
{
    if (!error) 
    {
        self.unreadMessages = [NSMutableArray arrayWithArray:objects];
       // set badge # to number of msgs
        if (self.unreadMessages.count > 0) 
        { 
            [[self navigationController] tabBarItem].badgeValue = [NSString stringWithFormat:@"%lu", (unsigned long)self.unreadMessages.count];
        }
        [self.tableView reloadData];
    }
}