Question

背景

请不要将此标记为重复。我已经尝试了所有其他相关的帖子，但他们没有为我工作。我已经看过无数的例子（StackOverflow / MBProgressHUD Demo /等）试图让它工作。我觉得大多数示例都已过时，因为某些方法已被弃用。这是我最接近的。

我希望代码执行的操作：

在开始连接到JSON之前，MBProgress HUD应显示默认加载屏幕“准备”。当我连接时，我希望模式在收到响应时更改为AnnularDeterminate。一旦完成加载，我希望进度条显示我将数据添加到字典的进度。完成后，将模式更改为CustomView，显示复选标记图像和“已完成”。

问题：

将显示MBProgress HUD。但是，它只显示默认加载屏幕下方的“正在准备...”，然后在进度为1.0后，它将使用复选标记自定义视图显示“已完成”。没有确定视图，我的更新进度介于两者之间。

我的代码

- (void)viewDidLoad
{
    buildingsDataArray = [[NSMutableArray alloc] init];
    MBProgressHUD *HUD = [MBProgressHUD showHUDAddedTo:self.view animated:YES];
    HUD.delegate = self;
    HUD.label.text = NSLocalizedString(@"Preparing...", @"HUD preparing title");
    [self connect];
    NSLog(@"End of setup");
}

- (void)connect
{
    NSURLRequest *request =[NSURLRequest requestWithURL:[NSURL URLWithString:buildingList]];
    connection = [NSURLConnection connectionWithRequest:request delegate:self];
    [connection start];

   NSLog(@"End of connect");
}


// Connection delegate
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
    NSLog(@"connection received response");
    [MBProgressHUD HUDForView:self.view].mode = MBProgressHUDModeAnnularDeterminate;
    NSLog(@"Changed mode");
}

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
    [webData appendData:data];
    NSLog(@"connection received data");
    [MBProgressHUD HUDForView:self.view].progress = 0.0f;
}

- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error
{
    NSLog(@"Fail with error - %@ %@", [error localizedDescription], [[error userInfo] objectForKey:NSURLErrorFailingURLStringErrorKey]);
    if ([[error localizedDescription] isEqualToString:@"The Internet connection appears to be offline."]) {
        //do something
    }
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
    NSArray *allDataArray = [NSJSONSerialization JSONObjectWithData:webData options:0 error:nil];
    float count = [allDataArray count];
    float c=1;
    if ([buildingsDataArray count]!=0)
        [buildingsDataArray removeAllObjects];
    for (NSDictionary *dataDict in allDataArray){ //from 1 to 6
        if ([[dataDict objectForKeyedSubscript:@"id"] intValue] != 0)
            [buildingsDataArray addObject:dataDict];
            usleep(200000);
            float p = c/count;
            [MBProgressHUD HUDForView:self.view].progress = p;
            NSLog(@"Progress: %f", [MBProgressHUD HUDForView:self.view].progress);
        });
        c++;
    }
    [MBProgressHUD HUDForView:self.view].customView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"Checkmark.png"]];
    [MBProgressHUD HUDForView:self.view].label.text = NSLocalizedString(@"Completed", @"HUD done title");
    [MBProgressHUD HUDForView:self.view].mode = MBProgressHUDModeCustomView;
    [[MBProgressHUD HUDForView:self.view] hideAnimated:YES afterDelay:1.0f];
}

这是我的控制台输出

End of connect
End of setup
connection received response
Changed mode
connection received data
connection finished loading
Progress: 0.166667
Progress: 0.333333
Progress: 0.500000
Progress: 0.666667
Progress: 0.833333
Progress: 1.000000

其他评论

当我尝试添加

时

dispatch_async(dispatch_get_main_queue()

在我的连接委托内的所有MBProgress方法调用之外，我再次获得默认加载屏幕。但是在进度达到1.0之后，确定的加载屏幕视图显示（完全加载）“已完成”，然后在延迟1.0后消失。中间仍然没有加载过程。此外，复选标记图像永远不会显示。我不认为这是做到这一点的方式。

执行此操作时的输出是：

End of connect
End of doSetup
connection received response
connection received data
connection finished loading
Changed mode
Progress: 0.166667
Progress: 0.333333
Progress: 0.500000
Progress: 0.666667
Progress: 0.833333
Progress: 1.000000

Answer 1

这是一个有用的参考，它基于不同线程上的UICalls： Is there a way to make drawRect work right NOW?

这是有用的：

在主线程上调用了NSURLConnection。因此，在连接委托调用完成之后，我的所有UI更新都没有发生。

因此，要解决此问题，我将连接放在后台线程中。

- (void)viewDidLoad{
    //...

    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0),^{
        NSURL *URL = [NSURL URLWithString:buildingList];
        NSMutableURLRequest *request =[NSMutableURLRequest requestWithURL:URL];
        connection = [[NSURLConnection alloc] initWithRequest:request delegate:self startImmediately:NO];
        [connection setDelegateQueue:[[NSOperationQueue alloc] init]];
        [connection start];
    });

}

在连接委托方法中，我用

包围了每个MBProgress调用

dispatch_async(dispatch_get_main_queue(), ^{
    //...
}

希望这有助于他人。我整天都花在这上面，这是一个如此简单的误解......

MBProgressHUD与NSURLConnection XCode 7

背景

我希望代码执行的操作：

问题：

我的代码

其他评论

1 个答案: