Error when Building Example branch

[hiroki-o]

Original report by philmzo NA (Bitbucket: philmzo, ).

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Just ran your example and imported AssetBundle Manager asset from the Asset Store to be sure nothing is missing and when building got:

InvalidOperationException: Operation is not valid due to the current state of the object
System.Collections.Stack.Peek () (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Collections/Stack.cs:321)
UnityEngine.GUILayoutUtility.EndLayoutGroup () (at C:/buildslave/unity/build/Runtime/IMGUI/Managed/GUILayoutUtility.cs:289)
UnityEngine.GUILayout.EndHorizontal () (at C:/buildslave/unity/build/Runtime/IMGUI/Managed/GUILayout.cs:291)
UnityEditor.EditorGUILayout.EndHorizontal () (at C:/buildslave/unity/build/Editor/Mono/EditorGUI.cs:6982)
UnityEditor.EditorGUILayout+HorizontalScope.CloseScope () (at C:/buildslave/unity/build/Editor/Mono/EditorGUI.cs:6942)
UnityEngine.GUI+Scope.Dispose () (at C:/buildslave/unity/build/Runtime/IMGUI/Managed/GUIBindings.cs:27)
AssetBundleGraph.AssetBundleGraphEditorWindow.DrawGUIToolBar () (at Assets/AssetBundleGraph/Editor/GUI/AssetBundleGraphEditorWindow.cs:582)
AssetBundleGraph.AssetBundleGraphEditorWindow.OnGUI () (at Assets/AssetBundleGraph/Editor/GUI/AssetBundleGraphEditorWindow.cs:820)
System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:222)

[hiroki-o]

Original comment by Hiroki Omae (Bitbucket: [Hiroki Omae](https://bitbucket.org/Hiroki Omae), ).

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This is a known issue due to holding Editor's GUI code for too long. It is an error should be fixed, but from user perspective there is no side effect from this error in using tool and building asset bundle.

In recent tool code (1.1) it still produces similar error such as following.

NullReferenceException: Object reference not set to an instance of an object
UnityEngine.GUILayoutUtility.BeginLayoutGroup (UnityEngine.GUIStyle style, UnityEngine.GUILayoutOption[] options, System.Type layoutType) (at /Users/builduser/buildslave/unity/build/Runtime/IMGUI/Managed/GUILayoutUtility.cs:263)
UnityEditor.EditorGUILayout.BeginHorizontal (UnityEngine.GUIContent content, UnityEngine.GUIStyle style, UnityEngine.GUILayoutOption[] options) (at /Users/builduser/buildslave/unity/build/Editor/Mono/EditorGUI.cs:7153)
UnityEditor.EditorGUILayout.BeginHorizontal (UnityEngine.GUILayoutOption[] options) (at /Users/builduser/buildslave/unity/build/Editor/Mono/EditorGUI.cs:7133)
UnityEditor.EditorGUILayout+HorizontalScope..ctor (UnityEngine.GUILayoutOption[] options) (at /Users/builduser/buildslave/unity/build/Editor/Mono/EditorGUI.cs:7111)
AssetBundleGraph.AssetBundleGraphEditorWindow.OnGUI () (at Assets/AssetBundleGraph/Editor/GUI/AssetBundleGraphEditorWindow.cs:819)
System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:222)

[hiroki-o]

Original comment by Hiroki Omae (Bitbucket: [Hiroki Omae](https://bitbucket.org/Hiroki Omae), ).

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I fixed this with a44ed7 . It is also in 1.1