随机异常java.lang.IllegalStateException：片段没有视图

Question

Many users are facing this exception. I have used several activities and fragments so i have no idea where it is arising from. This is definitely not related to DialogFragment since i don't even use it in my app.

Here is the complete stack trace:

0   java.lang.RuntimeException: Unable to start activity ComponentInfo{project/project.MainActivity}: java.lang.IllegalStateException: Fragment does not have a view
1       at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2426)
2       at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2490)
3       at android.app.ActivityThread.-wrap11(ActivityThread.java)
4       at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1354)
5       at android.os.Handler.dispatchMessage(Handler.java:102)
6       at android.os.Looper.loop(Looper.java:148)
7       at android.app.ActivityThread.main(ActivityThread.java:5443)
8       at java.lang.reflect.Method.invoke(Native Method)
9       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728)
10      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
11  Caused by: java.lang.IllegalStateException: Fragment does not have a view
12      at android.support.v4.app.Fragment$1.onFindViewById(SourceFile:1922)
13      at android.support.v4.app.FragmentManagerImpl.moveToState(SourceFile:1057)
14      at android.support.v4.app.FragmentManagerImpl.moveToState(SourceFile:1248)
15      at android.support.v4.app.FragmentManagerImpl.moveToState(SourceFile:1230)
16      at android.support.v4.app.FragmentManagerImpl.dispatchActivityCreated(SourceFile:2042)
17      at android.support.v4.app.Fragment.performActivityCreated(SourceFile:1976)
18      at android.support.v4.app.FragmentManagerImpl.moveToState(SourceFile:1092)
19      at android.support.v4.app.FragmentManagerImpl.moveToState(SourceFile:1248)
20      at android.support.v4.app.FragmentManagerImpl.moveToState(SourceFile:1230)
21      at android.support.v4.app.FragmentManagerImpl.dispatchActivityCreated(SourceFile:2042)
22      at android.support.v4.app.FragmentController.dispatchActivityCreated(SourceFile:165)
23      at android.support.v4.app.FragmentActivity.onStart(SourceFile:543)
24      at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1260)
25      at android.app.Activity.performStart(Activity.java:6261)
26      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2389)
27      ... 9 more
28  java.lang.IllegalStateException: Fragment does not have a view
29      at android.support.v4.app.Fragment$1.onFindViewById(SourceFile:1922)
30      at android.support.v4.app.FragmentManagerImpl.moveToState(SourceFile:1057)
31      at android.support.v4.app.FragmentManagerImpl.moveToState(SourceFile:1248)
32      at android.support.v4.app.FragmentManagerImpl.moveToState(SourceFile:1230)
33      at android.support.v4.app.FragmentManagerImpl.dispatchActivityCreated(SourceFile:2042)
34      at android.support.v4.app.Fragment.performActivityCreated(SourceFile:1976)
35      at android.support.v4.app.FragmentManagerImpl.moveToState(SourceFile:1092)
36      at android.support.v4.app.FragmentManagerImpl.moveToState(SourceFile:1248)
37      at android.support.v4.app.FragmentManagerImpl.moveToState(SourceFile:1230)
38      at android.support.v4.app.FragmentManagerImpl.dispatchActivityCreated(SourceFile:2042)
39      at android.support.v4.app.FragmentController.dispatchActivityCreated(SourceFile:165)
40      at android.support.v4.app.FragmentActivity.onStart(SourceFile:543)
41      at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1260)
42      at android.app.Activity.performStart(Activity.java:6261)
43      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2389)
44      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2490)
45      at android.app.ActivityThread.-wrap11(ActivityThread.java)
46      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1354)
47      at android.os.Handler.dispatchMessage(Handler.java:102)
48      at android.os.Looper.loop(Looper.java:148)
49      at android.app.ActivityThread.main(ActivityThread.java:5443)
50      at java.lang.reflect.Method.invoke(Native Method)
51      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728)
52      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)

Any idea what is this exception related to?

Answer 1

看起来您在MainActivity中使用了Fragment，并且onCreateView的返回不是有效的视图（可能为null）。