{"action":"created","issue":{"url":"https://api.github.com/repos/mapbox/mbxmapkit/issues/153","labels_url":"https://api.github.com/repos/mapbox/mbxmapkit/issues/153/labels{/name}","comments_url":"https://api.github.com/repos/mapbox/mbxmapkit/issues/153/comments","events_url":"https://api.github.com/repos/mapbox/mbxmapkit/issues/153/events","html_url":"https://github.com/mapbox/mbxmapkit/issues/153","id":57351310,"number":153,"title":"[VKTileKeyMap enumerateKeysAndObjectsUsingBlock:]","user":{"login":"ghost","id":10137,"avatar_url":"https://avatars.githubusercontent.com/u/10137?v=3","gravatar_id":"","url":"https://api.github.com/users/ghost","html_url":"https://github.com/ghost","followers_url":"https://api.github.com/users/ghost/followers","following_url":"https://api.github.com/users/ghost/following{/other_user}","gists_url":"https://api.github.com/users/ghost/gists{/gist_id}","starred_url":"https://api.github.com/users/ghost/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/ghost/subscriptions","organizations_url":"https://api.github.com/users/ghost/orgs","repos_url":"https://api.github.com/users/ghost/repos","events_url":"https://api.github.com/users/ghost/events{/privacy}","received_events_url":"https://api.github.com/users/ghost/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/mapbox/mbxmapkit/labels/bug","name":"bug","color":"e10c02"}],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":10,"created_at":"2015-02-11T17:51:08Z","updated_at":"2015-05-20T15:33:42Z","closed_at":null,"body":"Frequently happening after 0.7.0. Any Ideas?\r\n\r\n0   libobjc.A.dylib                      0x0000000193b4bbd0 objc_msgSend + 16\r\n1   VectorKit                            0x00000001907e0880 __50-[VKRasterOverlayTileSource invalidateRect:level:]_block_invoke_2 + 56\r\n2   VectorKit                            0x000000019048d8c8 -[VKTileKeyMap enumerateKeysAndObjectsUsingBlock:] + 72\r\n3   VectorKit                            0x000000019048d854 -[VKTilePool enumerateKeysAndObjectsUsingBlock:] + 92\r\n4   VectorKit                            0x00000001907e07dc __50-[VKRasterOverlayTileSource invalidateRect:level:]_block_invoke + 176\r\n5   libdispatch.dylib                    0x000000019417d3ac _dispatch_call_block_and_release + 20\r\n6   libdispatch.dylib                    0x000000019417d36c _dispatch_client_callout + 12\r\n7   libdispatch.dylib                    0x0000000194181980 _dispatch_main_queue_callback_4CF + 928\r\n8   CoreFoundation                       0x00000001833a5fa4 __CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__ + 8\r\n9   CoreFoundation                       0x00000001833a404c __CFRunLoopRun + 1488\r\n10  CoreFoundation                       0x00000001832d10a4 CFRunLoopRunSpecific + 392\r\n11  GraphicsServices                     0x000000018c46b5a4 GSEventRunModal + 164\r\n12  UIKit                                0x0000000187c02aa4 UIApplicationMain + 1484\r\n13  Navigator2                           0x000000010010d400 main (main.m:6)\r\n14  libdyld.dylib                        0x00000001941a6a08 start + 0"},"comment":{"url":"https://api.github.com/repos/mapbox/mbxmapkit/issues/comments/103927730","html_url":"https://github.com/mapbox/mbxmapkit/issues/153#issuecomment-103927730","issue_url":"https://api.github.com/repos/mapbox/mbxmapkit/issues/153","id":103927730,"user":{"login":"incanus","id":17722,"avatar_url":"https://avatars.githubusercontent.com/u/17722?v=3","gravatar_id":"","url":"https://api.github.com/users/incanus","html_url":"https://github.com/incanus","followers_url":"https://api.github.com/users/incanus/followers","following_url":"https://api.github.com/users/incanus/following{/other_user}","gists_url":"https://api.github.com/users/incanus/gists{/gist_id}","starred_url":"https://api.github.com/users/incanus/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/incanus/subscriptions","organizations_url":"https://api.github.com/users/incanus/orgs","repos_url":"https://api.github.com/users/incanus/repos","events_url":"https://api.github.com/users/incanus/events{/privacy}","received_events_url":"https://api.github.com/users/incanus/received_events","type":"User","site_admin":false},"created_at":"2015-05-20T15:33:42Z","updated_at":"2015-05-20T15:33:42Z","body":"Very useful @s219. My original thinking was along the lines of offline map tiles being so much faster to fetch that maybe we were exposing a bug or race condition in the `VK*` framework, but this sounds like a better lead. Particularly _because_ of the tight turnaround allowing for rapid looping like this. \r\n\r\nI can't think of a good way to indicate at the overlay level whether tiles are valid or not, so I wonder if simply returning an _alpha transparent_ tile for missing tiles would work? So, your solution @s219 but see-through? Will investigate. "}}