ActivityView未顯示

Question

我正在嘗試向我的應用程序添加下載進度視圖，並且它在調試預覽中顯示時並未實際顯示在設備上。任何人都可以向我解釋這個嗎？

這裏是調試的截圖和一些代碼：

- (void)updateDownloadProgressWithBatchIndex:(int)index contentName:(NSString *)name 
{ 
    CGSize size = self.view.bounds.size; 

    _loadingView = [[UIView alloc] initWithFrame:CGRectMake(75, 155, 170, 170)]; 
    _loadingView.backgroundColor = [UIColor blackColor]; 
    _loadingView.clipsToBounds = YES; 
    _loadingView.layer.cornerRadius = 10.0; 
    [_loadingView setCenter:CGPointMake(size.width/2, size.height/2)]; 

    _activityView = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhite]; 
    _activityView.frame = CGRectMake(65, 40, _activityView.bounds.size.width,  _activityView.bounds.size.height); 
    _activityView.hidden = NO; 
    [_activityView setCenter:CGPointMake(size.width/2, size.height/2)]; 
    [_loadingView addSubview:_activityView]; 

    _loadingLabel = [[UILabel alloc] initWithFrame:CGRectMake(20, 115, 130, 22)]; 
    _loadingLabel.backgroundColor = [UIColor clearColor]; 
    _loadingLabel.textColor = [UIColor whiteColor]; 
    _loadingLabel.adjustsFontSizeToFitWidth = YES; 
    _loadingLabel.textAlignment = UITextAlignmentCenter; 
    _loadingLabel.text = [NSString stringWithFormat:@"Batch %i downloading...", index]; 
    [_loadingView addSubview:_loadingLabel]; 

    [self.view addSubview:_loadingView]; 
    _loadingView.hidden = NO; 
    UIView *v = self.view; 
    [_activityView startAnimating]; 
} 

Answer 1

我要帶胡亂猜測 - 它必須是野生的，因爲你拒絕出示你的代碼 - 在撥打updateDownloadProgress後，您正在進行同步聯網。這是問題的原因。因此，活動視圖無法開始旋轉將是診斷問題，因此問題是同步網絡，這是一個禁忌。