Problem with ios plugin to show web view

I write an obj-c method with signature :

-(void) CalliOSWebView 

in WebController.h, it show web page using native iOS web view (in xcode this method work fine). and i have 4 files WebController.h, WebController.m, ViewWebCaller.h and ViewWebCaller.m. i put this files into “Assets/Plugins/iOS” folder. then i use this code

public class CalliosWeb : MonoBehaviour
{

 	[DllImport ("__Internal")]
	public static extern void CalliOSWebView();

	public static void CallView()
	{
		Debug.Log("Try to call web view");
		CalliOSWebView();
	}	

to add this plugin in unity. and i try to call CalliosWeb.CallView when i press button. but when i try to build and run this code in iOS device, xcode tells me that i have errors

Undefined symbols for architecture armv7:
“__CalliOSWebView”, referenced from:
RegisterMonoModules() in RegisterMonoModules.o
ld: symbol(s) not found for architecture armv7
clang: error: linker command failed with exit code 1 (use -v to see invocation)

so can anyone help me to solve this problem. and maybe give some links that shows how connect plugins in unity. thanks!

I have used following plugins for web view in iOS and Android

iOS : Web View in iOS | Integration | Unity Asset Store

Android : Web View for Android | Integration | Unity Asset Store