What is causing this in android webView?

I am getting the following exception and not able to debug it.

Please help.

    04-20 10:55:58.052: WARN/dalvikvm(9255): threadid=8: thread exiting with uncaught exception (group=0x400207d8)
       04-20 10:55:58.092: ERROR/AndroidRuntime(9255): FATAL EXCEPTION: WebViewCoreThread  
     04-20 10:55:58.092: ERROR/AndroidRuntime(9255): android.view.ViewRoot$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.  
     04-20 10:55:58.092: ERROR/AndroidRuntime(9255):     at android.view.ViewRoot.checkThread(ViewRoot.java:2812)  
     04-20 10:55:58.092: ERROR/AndroidRuntime(9255):     at android.view.ViewRoot.invalidateChild(ViewRoot.java:607)  
     04-20 10:55:58.092: ERROR/AndroidRuntime(9255):     at android.view.ViewRoot.invalidateChildInParent(ViewRoot.java:633)  
  04-20 10:55:58.092: ERROR/AndroidRuntime(9255):     at android.view.ViewGroup.invalidateChild(ViewGroup.java:2505)
 04-20 10:55:58.092: ERROR/AndroidRuntime(9255):     at android.view.View.invalidate(View.java:5115)
 04-20 10:55:58.092: ERROR/AndroidRuntime(9255):     at android.webkit.WebView.viewInvalidate(WebView.java:2565)
 04-20 10:55:58.092: ERROR/AndroidRuntime(9255):     at android.webkit.WebView.invalidateContentRect(WebView.java:2584)
 04-20 10:55:58.092: ERROR/AndroidRuntime(9255):     at android.webkit.WebView.access$6200(WebView.java:304)
 04-20 10:55:58.092: ERROR/AndroidRuntime(9255):     at android.webkit.WebView$PrivateHandler.handleMessage(WebView.java:7860)
 04-20 10:55:58.092: ERROR/AndroidRuntime(9255):     at android.os.Handler.dispatchMessage(Handler.java:99)
 04-20 10:55:58.092: ERROR/AndroidRuntime(9255):     at android.os.Looper.loop(Looper.java:123)
 04-20 10:55:58.092: ERROR/AndroidRuntime(9255):     at android.webkit.WebViewCore$WebCoreThread.run(WebViewCore.java:637)
 04-20 10:55:58.092: ERROR/AndroidRuntime(9255):     at java.lang.Thread.run(Thread.java:1096)
 04-20 10:55:58.102: WARN/ActivityManager(172):   Force finishing activity com.Hy5/.activity.Hy5CanvasActivity
 

thanks
Sneha

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