【unity】android错误Field currentActivity or type signature not found

错误现象：

UnityEngine._AndroidJNIHelper.GetFieldID (System.IntPtr jclass, System.String fieldName, System.String signature, System.Boolean isStatic) [0x00082] in <7dbed83b26eb419d871f118701305875>:0 
  at UnityEngine.AndroidJNIHelper.GetFieldID (System.IntPtr javaClass, System.String fieldName, System.String signature, System.Boolean isStatic) [0x00001] in <7dbed83b26eb419d871f118701305875>:0 
  at UnityEngine._AndroidJNIHelper.GetFieldID[ReturnType] (System.IntPtr jclass, System.String fieldName, System.Boolean isStatic) [0x00012] in <7dbed83b26eb419d871f118701305875>:0 
  at UnityEngine.AndroidJNIHelper.GetFieldID[FieldType] (System.IntPtr jclass, System.String fieldName, System.Boolean isStatic) [0x00001] in <7dbed83b26eb419d871f118701305875>:0 
  at UnityEngine.AndroidJavaObject._GetStatic[FieldType] (System.String fieldName) [0x0000c] in <7dbed83b26eb419d871f118701305875>:0 
  at UnityEngine.AndroidJavaObject.GetStatic[FieldType] (System.String fieldName) [0x00001] in <7dbed83b26eb419d871f118701305875>:0 
  at ClipboardHelper.Copy (System.String text) [0x00030] in <c2a60710cec84649b7ea22f96db75d0c>:0 
  at OnButtonClick (System.Int32 index) [0x00085] in <c2a60710cec84649b7ea22f96db75d0c>:0 |Field currentActivity or type signature  not found

错误原因：

主要是平台错误，比如在editor上面运行的代码，运行到了Android的代码，导致在editor上面运行的时候找不到对应的signature 错误。一般是UNITY_EDITOR宏是关闭的导致的。