makes potentially long-running purge methods run as background tasks

artgillespie · Aug 22, 2013 · fcdeb2c · fcdeb2c
1 parent 9e9d6fe
commit fcdeb2c
Showing 1 changed file with 10 additions and 0 deletions.
diff --git a/OGImage/OGImageCache.m b/OGImage/OGImageCache.m
@@ -122,10 +122,15 @@ - (void)setImage:(__OGImage *)image forKey:(NSString *)key {
 
 - (void)purgeCache:(BOOL)wait {
     [_memoryCache removeAllObjects];
+    UIBackgroundTaskIdentifier taskId = UIBackgroundTaskInvalid;
+    taskId = [[UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler:^{
+        [[UIApplication sharedApplication] endBackgroundTask:taskId];
+    }];
     void (^purgeFilesBlock)(void) = ^{
         for (NSURL *url in [[NSFileManager defaultManager] enumeratorAtURL:OGImageCacheURL() includingPropertiesForKeys:nil options:0 errorHandler:nil]) {
             [[NSFileManager defaultManager] removeItemAtURL:url error:nil];
         }
+        [[UIApplication sharedApplication] endBackgroundTask:taskId];
     };
     if (YES == wait) {
         dispatch_sync(_cacheFileTasksQueue, purgeFilesBlock);
@@ -159,6 +164,10 @@ - (void)purgeMemoryCacheForKey:(NSString *)key andWait:(BOOL)wait {
 }
 
 - (void)purgeDiskCacheOfImagesLastAccessedBefore:(NSDate *)date {
+    UIBackgroundTaskIdentifier taskId = UIBackgroundTaskInvalid;
+    taskId = [[UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler:^{
+        [[UIApplication sharedApplication] endBackgroundTask:taskId];
+    }];
     dispatch_async(_cacheFileTasksQueue, ^{
         NSURL *cacheURL = OGImageCacheURL();
         for (NSURL *fileURL in [[NSFileManager defaultManager] enumeratorAtURL:cacheURL includingPropertiesForKeys:@[NSURLContentAccessDateKey] options:NSDirectoryEnumerationSkipsHiddenFiles errorHandler:nil]) {
@@ -170,6 +179,7 @@ - (void)purgeDiskCacheOfImagesLastAccessedBefore:(NSDate *)date {
                 [[NSFileManager defaultManager] removeItemAtURL:fileURL error:nil];
             }
         }
+        [[UIApplication sharedApplication] endBackgroundTask:taskId];
     });
 }