ios7进入页面直接crash。

信息如下:
[NSConcreteMapTable fd_allObjects]: unrecognized selector sent to instance 0x1583bdb0
0x2f7f2159 CFArrayApplyFunction + 36
14 UIKit 0x3267c285 + 144
15 UIKit 0x321e422b + 126
16 CoreFoundation 0x2f7f2159 CFArrayApplyFunction + 36
17 UIKit 0x3267c285 + 144
18 UIKit 0x321e422b + 126
19 CoreFoundation 0x2f7f2159 CFArrayApplyFunction + 36
20 UIKit 0x3267c285 + 144
21 UIKit 0x321e422b + 126
22 CoreFoundation 0x2f7f2159 CFArrayApplyFunction + 36
23 UIKit 0x3267c285 + 144
24 UIKit 0x321e422b + 126
25 CoreFoundation 0x2f7f2159 CFArrayApplyFunction + 36
26 UIKit 0x3267c285 + 144
27 UIKit 0x321e422b + 126
28 CoreFoundation 0x2f7f2159 CFArrayApplyFunction + 36
29 UIKit 0x3267c285 + 144
30 UIKit 0x321e422b + 126
31 CoreFoundation 0x2f7f2159 CFArrayApplyFunction + 36
32 UIKit 0x3267c285 + 144
33 UIKit 0x321e422b + 126
34 CoreFoundation 0x2f7f2159 CFArrayApplyFunction + 36
35 UIKit 0x3267c285 + 144
36 UIKit 0x321e422b + 126
37 CoreFoundation 0x2f7f2159 CFArrayApplyFunction + 36
38 UIKit 0x3267c285 + 144
39 UIKit 0x321e422b + 126
40 Foundation 0x30225d33 + 210
41 UIKit 0x321fe0c7 + 218
42 UIKit 0x320f0543 + 54
43 UIKit 0x32229f03 + 1686
44 UIKit 0x320f02e5 + 380
45 QuartzCore 0x31d6c31b + 142
46 QuartzCore 0x31d67b3f + 350
47 QuartzCore 0x31d679d1 + 16
48 QuartzCore 0x31d673e5 + 228
49 QuartzCore 0x31d671f7 + 314
50 QuartzCore 0x31d60f1d + 56
51 CoreFoundation 0x2f889ff9 + 20
52 CoreFoundation 0x2f887987 + 286
53 CoreFoundation 0x2f887cd3 + 738
54 CoreFoundation 0x2f7f2729 CFRunLoopRunSpecific + 524
55 CoreFoundation 0x2f7f250b CFRunLoopRunInMode + 106
56 GraphicsServices 0x347616d3 GSEventRunModal + 138
57 UIKit 0x32153871 UIApplicationMain + 1136
58 YWArt 0x00178257 main + 106
59 libdyld.dylib

首先，在 iOS 7 上进入页面时复现崩溃，并检查该入口点涉及的 Objective-C 代码。使用报告中的 NSConcreteMapTable selector 错误和堆栈跟踪来缩小原因范围。页面在 iOS 7 上能够打开且不发生崩溃，同时保留现有行为，即表示完成。

由索引模型根据 Issue 内容生成。