Databases
StackOverflow2013
Postsdbo
POWeb Server status checking using timer
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POWeb Server status checking using timer
    primarykey
    data
    text
    <p>I have to download files from my server. Multiple download is supported. When i click download i have to check for network connectivity and server connectivity, <strong>Which is done</strong>.</p> <p>Here is the problem!</p> <p>During download if the server become unavailable, it creates some problems. So I have to check for server connectivity after 5 sec, and have to display an alert that the server is down. I used a timer to check the connectivity. But the problem is that, during multiple downloads the alert view is displayed as many times as the number of downloads. And if the server becomes available in between then the app freezes. But I could see that the timer code is still working..</p> <p>Sample code:</p> <pre><code> -(void) myFunction { if ([networkCheck isHostReachable]) { if (![ServerConnectivity isServerUp:myUrl]) { serverStatusAlert = YES; } if (serverStatusAlert) { UIAlertView *serverDownAlert = [[UIAlertView alloc]initWithTitle:@"Error" message:@"Server is down. Please try after sometimes." delegate:self cancelButtonTitle:nil otherButtonTitles:@"Ok",nil]; [serverDownAlert show]; [serverDownAlert release]; serverDownAlert = nil; [self cancelAllDownload]; connectivityTimer = [NSTimer scheduledTimerWithTimeInterval:5.0 target:self selector:@selector(checkServerStatus) userInfo:nil repeats:YES]; } } else { NSLog(@"No network connection..."); } } -(void)checkServerStatus { if ([ServerConnectivity isServerUp:myUrl]) { [connectivityTimer invalidate]; connectivityTimer = nil; serverStatusAlert = NO; //function to resume downloads } else { //pause downloads } } </code></pre>
    singulars
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PTQuestion
    1. This table or related slice is empty.
    1. USNibin V
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. COYou should consider enforcing the following: If the number of current downloads is one - throw the error. If there's more than one current download then throw it once. If an error is shown, set some BOOL like errorShown = YES; and check against this before potentially showing another error.
      singulars
      1. POWeb Server status checking using timer
      1. USLuke
    2. COThanks @Luke.. I found out a problem with my logic. The alert view will be displayed every time, since i am not changing the bool variable inside the if condition and its outside `if (![ServerConnectivity isServerUp:myUrl])` code. That problem is solved. **But when the server is available again, the app gets freezes for sometimes. Can anything be done with this problem. I think its the time taken for pinging back again to the server?**
      singulars
      1. POWeb Server status checking using timer
      1. USNibin V
    3. COWhen you say it freezes - do you mean the app actually locks up/becomes unresponsive or is this due to it waiting for a response from your server?
      singulars
      1. POWeb Server status checking using timer
      1. USLuke
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload