假设有一个像
这样的完成块typedef void(^JSAPICallback)(id result);
和绑定类
@protocol JSProtocol<JSExport>
- (void)initAPI:(JSAPICallback)success;
@end
@interface JSObject : NSObject<JSProtocol>
- (void)initAPI:(JSAPICallback)success error:(JSAPICallback)error;
@end
@implementation JSObject
- (void)initAPI:(JSAPICallback)success {
[[API sharedInstance] initialize:^(id results, NSError *error) {
if(error==nil) {
success(results)
} else {
error()
}
}];
}
}
如果我尝试在JSContext中将其绑定到tvOS TVApplicationControllerDelegate委托中的- (void)appController:(TVApplicationController *)appController evaluateAppJavaScriptInContext:(JSContext *)jsContext {
JSObject *jsObject = [[JSObject alloc] init];
[jsContext setObject:jsObject forKeyedSubscript:@"jsobject"];
[jsContext setExceptionHandler:^(JSContext *context, JSValue *value) {
NSLog(@"%@", value);
}];
}
，请执行以下操作：
2015-10-09 23:33:16.669 TestbedTV[9707:3524754] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[__NSPlaceholderDictionary initWithObjects:forKeys:count:]: attempt to insert nil object from objects[0]'
*** First throw call stack:
(
0 CoreFoundation 0x000000011008f105 __exceptionPreprocess + 165
1 libobjc.A.dylib 0x000000010fb07deb objc_exception_throw + 48
2 CoreFoundation 0x000000010ff9206e -[__NSPlaceholderDictionary initWithObjects:forKeys:count:] + 318
3 CoreFoundation 0x000000010ffa43bb +[NSDictionary dictionaryWithObjects:forKeys:count:] + 59
4 JavaScriptCore 0x000000011905d388 -[JSObjCClassInfo allocateConstructorAndPrototype] + 2664
5 JavaScriptCore 0x000000011905e25f -[JSObjCClassInfo prototype] + 47
6 JavaScriptCore 0x000000011905e0ab -[JSObjCClassInfo wrapperForObject:] + 587
7 JavaScriptCore 0x000000011905e737 -[JSWrapperMap jsWrapperForObject:] + 423
8 JavaScriptCore 0x0000000118fdce80 -[JSContext(Internal) wrapperForObjCObject:] + 64
9 JavaScriptCore 0x0000000119054238 _ZL24objectToValueWithoutCopyP9JSContextP11objc_object + 760
10 JavaScriptCore 0x000000011905053a _Z13objectToValueP9JSContextP11objc_object + 74
11 JavaScriptCore 0x0000000119051ad9 -[JSValue setValue:forProperty:] + 137
12 TestbedTV 0x000000010eeb42cd -[AppDelegate appController:evaluateAppJavaScriptInContext:] + 141
13 TVMLKit 0x000000011048d3be -[TVApplicationController appContext:evaluateAppJavaScriptInContext:] + 889
14 ITMLKit 0x000000011b47d431 -[IKAppContext(JS) evaluateFoundationJS] + 2566
15 ITMLKit 0x000000011b4a56b3 -[IKAppContext _startWithScript:scriptUrl:] + 262
16 ITMLKit 0x000000011b4a52a5 -[IKAppContext _startWithURL:urlTrusted:] + 1277
17 ITMLKit 0x000000011b4a37e7 __21-[IKAppContext start]_block_invoke + 46
18 ITMLKit 0x000000011b4a6633 -[IKAppContext _sourcePerform] + 379
19 ITMLKit 0x000000011b4a647d IKRunLoopSourcePerformCallBack + 34
20 CoreFoundation 0x000000010ffbb1b1 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
21 CoreFoundation 0x000000010ffb10dc __CFRunLoopDoSources0 + 556
22 CoreFoundation 0x000000010ffb0593 __CFRunLoopRun + 867
23 CoreFoundation 0x000000010ffaffa8 CFRunLoopRunSpecific + 488
24 CoreFoundation 0x0000000110063201 CFRunLoopRun + 97
25 ITMLKit 0x000000011b4a62ea -[IKAppContext _jsThreadMain] + 337
26 Foundation 0x000000010f79224b __NSThread__start__ + 1198
27 libsystem_pthread.dylib 0x000000011311505a _pthread_body + 131
28 libsystem_pthread.dylib 0x0000000113114fd7 _pthread_body + 0
29 libsystem_pthread.dylib 0x00000001131123ed thread_start + 13
)
libc++abi.dylib: terminating with uncaught exception of type NSException
我遇到了崩溃：
@protocol JSProtocol<JSExport>
- (void)initAPI:(NSString*)options;
@end
似乎JavaScriptCore无法绑定完成块。有一个简单的函数，像这样的简单参数
tvOS9.0相反，绑定将按预期工作。
这种情况发生在iOS9.1，但我认为它也会在vote_count中崩溃。
最有可能获得一些想法的问题是ObjectiveC and JavaScriptCore: Will using this method of calling CallBacks cause memory issues?。