viewDisappear時停止Loop的最佳方法是什么

Question

我的目標是當viewDidLoad以頻率0,8秒開始（刷新）並且在視圖消失后停止（刷新）。

在viewDidLoad調用（refres）函數：

@proptery disAppear;
- (void)viewDidLoad {
   [super viewDidLoad];
   NSLog(@"TeklifVer-viewDidLoad()");
   self.disAppear = NO;
   [self refresh];    
}

- (void)viewDidDisappear:(BOOL)animated {
   NSLog(@"viewDiddisappear"); 
   self.disAppear = YES;
}

on（refresh）函數調用（refresh）： [self performSelector:@selector(refresh) withObject:nil afterDelay:0.8]; 如果不是disAppear。

- (void) refresh
{
    NSLog(@"refresh");

    ...
    [operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {

        NSDictionary * responseDictionary = (NSDictionary *)responseObject;

        if (!self.disAppear) {
            ...
            TeklifVerModel * teklifVerModel = [[TeklifVerModel alloc] initWithDictionary:responseDictionary];

            //init labels
            ...

            @try {
                if (teklifVerModel.ihaleStatus == 2) {
                    self.nextPage = true;
                } else if (teklifVerModel.ihaleStatus == 5) {
                    self.ihaleListesi = true;
                }
            }
            @catch (NSException *exception) {
                NSLog(@"error: %@", exception);
            }
        }

    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
        NSLog(@"error: %@", error);
    }];
    [operation start];

    if (self.nextPage) {
        UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
        IhaleViewController * ihale = [storyboard instantiateViewControllerWithIdentifier:@"ihaleViewController"];
        [self presentViewController:ihale animated:YES completion:nil];
    } else if (self.ihaleListesi) {
        UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
        IhaleListesiViewController * ihaleListesi = [storyboard instantiateViewControllerWithIdentifier:@"ihaleListesi"];
        [self presentViewController:ihaleListesi animated:YES completion:nil];
    } else if(!self.disAppear) {
        [self performSelector:@selector(refresh) withObject:nil afterDelay:0.8];
    }
}  

日志

2015-07-03 15:51:24.918 uztb[729:129628] refresh
2015-07-03 15:51:25.189 uztb[729:129628] viewDidDisappear
2015-07-03 15:51:25.720 uztb[729:129628] refresh
2015-07-03 15:51:26.522 uztb[729:129628] refresh
2015-07-03 15:51:27.324 uztb[729:129628] refresh
2015-07-03 15:51:28.127 uztb[729:129628] refresh

我的問題是當viewDisapper仍然執行某些（刷新）時。 有時（刷新）永遠不會停止。 所以當這個視圖再次加載多個（刷新）線程時執行

問題：viewDisappear停止（刷新）線程的最佳方法是什么？

Answer 1

嘗試並在viewDidDisappear cancelPerformSelectorsWithTarget方法。 更多信息。