这确实会在 iOS 9.3 上的主线程上调用时导致死锁(在 iPhone 6 和 iPhone 6 Plus 上测试)。
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回溯:
* thread #1: tid = 0x41840, 0x0000000180ac1014 libsystem_kernel.dylib`semaphore_wait_trap + 8, queue = 'com.apple.main-thread', stop reason = signal SIGSTOP
* frame #0: 0x0000000180ac1014 libsystem_kernel.dylib`semaphore_wait_trap + 8
frame #1: 0x000000010023fa20 libdispatch.dylib`_dispatch_semaphore_wait_slow + 244
frame #2: 0x0000000180bda934 libxpc.dylib`xpc_connection_send_message_with_reply_sync + 204
frame #3: 0x000000018276a238 MobileCoreServices`_LSStartOpenOperation + 232
frame #4: 0x0000000182791efc MobileCoreServices`-[LSOpenOperation main] + 1160
frame #5: 0x0000000182771bc0 MobileCoreServices`-[LSApplicationWorkspace openURL:withOptions:error:] + 472
frame #6: 0x000000018633cdd8 UIKit`-[UIApplication _openURL:] + 356
frame #7: 0x0000000100096c04 MyApp`__29-[ViewController someMethod]_block_invoke(.block_descriptor=0x0000000125d37e20) + 216 at ViewController.m:57
frame #8: 0x000000010022da7c libdispatch.dylib`_dispatch_call_block_and_release + 24
frame #9: 0x000000010022da3c libdispatch.dylib`_dispatch_client_callout + 16
frame #10: 0x00000001002334e4 libdispatch.dylib`_dispatch_main_queue_callback_4CF + 2096
frame #11: 0x0000000180ef8dd8 CoreFoundation`__CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__ + 12
frame #12: 0x0000000180ef6c40 CoreFoundation`__CFRunLoopRun + 1628
frame #13: 0x0000000180e20d10 CoreFoundation`CFRunLoopRunSpecific + 384
frame #14: 0x0000000182708088 GraphicsServices`GSEventRunModal + 180
frame #15: 0x00000001860f5f70 UIKit`UIApplicationMain + 204
frame #16: 0x00000001000970d0 MyApp`main(argc=1, argv=0x000000016fd6fae8) + 124 at main.m:14
frame #17: 0x00000001809be8b8 libdyld.dylib`start + 4
我发现将整个调用包装在一个dispatch_async
块中解决了这个问题:
dispatch_async(dispatch_get_main_queue(), ^{
if ([[UIApplication sharedApplication] canOpenURL:url]) {
[[UIApplication sharedApplication] openURL:url];
}
});
我会向 Apple 提交 Radar 并将其发布在Open Radar上。
看起来这是在 iOS 9.3.1 中修复的:
修复了在 Safari 和其他应用程序中点击链接后导致应用程序无响应的问题。