我正在尝试将 RevMobAds 集成到我的 iOS 应用程序中。它在第一行就崩溃了，
[RevMobAds startSessionWithAppID:@"myAppID"];
如何解决这个问题？我按照此处给出的说明进行操作：http: //sdk.revmob.com/ios.html。我正在使用 SDK 5.6.0。请告诉我。以下是崩溃日志。
* thread #1: tid = 0x1f03, 0x029c109f libobjc.A.dylib`objc_msgSend + 19, stop reason = EXC_BAD_ACCESS (code=2, address=0x0)
frame #0: 0x029c109f libobjc.A.dylib`objc_msgSend + 19
frame #1: 0x029acb2e libobjc.A.dylib`objc_setProperty_non_gc + 62
frame #2: 0x029acd0d libobjc.A.dylib`objc_setProperty + 47
frame #3: 0x0016cbb6 MyApp`-[RevMobHttpClient setOnSuccess:] + 63 at RevMobHttpClient.h:9
frame #4: 0x0016c621 MyApp`-[RevMobHttpClient post:toUrl:onSuccess:onFailure:] + 56 at RevMobHttpClient.m:112
frame #5: 0x0016be43 MyApp`+[RevMobHttpClient post:toUrl:onSuccess:onFailure:] + 195 at RevMobHttpClient.m:45
frame #6: 0x001645d4 MyApp`-[RevMobSessionStarter start] + 203 at RevMobSessionStarter.m:42
frame #7: 0x00161bfb MyApp`+[RevMobSessionManager startSessionWithAppID:delegate:testingMode:sdkName:sdkVersion:] + 467 at RevMobSessionManager.m:145
frame #8: 0x0015ce99 MyApp`+[RevMobAds startSessionWithAppID:delegate:testingMode:sdkName:sdkVersion:] + 145 at RevMobAds.m:111
frame #9: 0x0015cf08 MyApp`+[RevMobAds startSessionWithAppID:] + 75 at RevMobAds.m:126
frame #10: 0x00002b5f MyApp`-[MyAppAppDelegate application:didFinishLaunchingWithOptions:] + 111 at MyAppAppDelegate.m:26
frame #11: 0x00b3f7b7 UIKit`-[UIApplication _handleDelegateCallbacksWithOptions:isSuspended:restoreState:] + 266
frame #12: 0x00b3fda7 UIKit`-[UIApplication _callInitializationDelegatesForURL:payload:suspended:] + 1248
frame #13: 0x00b40fab UIKit`-[UIApplication _runWithURL:payload:launchOrientation:statusBarStyle:statusBarHidden:] + 805
frame #14: 0x00b52315 UIKit`-[UIApplication handleEvent:withNewEvent:] + 1022
frame #15: 0x00b5324b UIKit`-[UIApplication sendEvent:] + 85
frame #16: 0x00b44cf8 UIKit`_UIApplicationHandleEvent + 9874
frame #17: 0x02eb8df9 GraphicsServices`_PurpleEventCallback + 339
frame #18: 0x02eb8ad0 GraphicsServices`PurpleEventCallback + 46
frame #19: 0x02efdbf5 CoreFoundation`__CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 53
frame #20: 0x02efd962 CoreFoundation`__CFRunLoopDoSource1 + 146
frame #21: 0x02f2ebb6 CoreFoundation`__CFRunLoopRun + 2118
frame #22: 0x02f2df44 CoreFoundation`CFRunLoopRunSpecific + 276
frame #23: 0x02f2de1b CoreFoundation`CFRunLoopRunInMode + 123
frame #24: 0x00b407da UIKit`-[UIApplication _run] + 774
frame #25: 0x00b4265c UIKit`UIApplicationMain + 1211
frame #26: 0x00002abd MyApp`main + 125 at main.m:14
谢谢。