How to handle the AmazonServiceException thrown when disconnected with network - exception

Question

I'm using AWS mobile SDK for Xamarin (http://aws.amazon.com/about-aws/whats-new/2014/10/09/aws-mobile-sdk-for-xamarin-available-on-awslabs/) and i got a problem when i use GetObjectAsync() method to get files from my S3 Bucket. My code:
private async Task<string> GetObjectFromAmazonS3(S3Object s3Object, string fileContent, string bucketName)
{
AWSCredentials credential = new BasicAWSCredentials(Constants.S3AccessKey, Constants.S3SecretKey);
_amazonS3Client = new AmazonS3Client(credential, Amazon.RegionEndpoint.EUCentral1);
_amazonS3Client.ExceptionEvent += ClientExceptionHandler;
GetObjectRequest getObjectRequest = new GetObjectRequest
{
BucketName = bucketName,
Key = s3Object.Key
};
GetObjectResponse getObjectResponse = await _amazonS3Client.GetObjectAsync(getObjectRequest);
using (Stream responseStream = getObjectResponse.ResponseStream)
using (StreamReader reader = new StreamReader(responseStream))
{
fileContent = reader.ReadToEnd();
}
Logger.Log(Logger.Category.Debugging, "Download S3 Objects to the phone", "Get object " + s3Object.Key + " successfully");
return fileContent;
}
The problem is that when the application waiting for the response from GetObjectAsync() method, the phone is disconnected with the network then i got an exception:
2015-03-03T07:23:27.582Z,Debugging,UnhandledException(Android),Amazon.Runtime.AmazonServiceException: A WebException with status NameResolutionFailure was thrown.
---> System.Net.WebException: Error: NameResolutionFailure
==> at System.Net.HttpWebRequest.EndGetResponse (IAsyncResult asyncResult) [0x00000] in <filename unknown>:0
==> at System.Threading.Tasks.TaskFactory`1[System.Net.WebResponse].InnerInvoke (System.Threading.Tasks.TaskCompletionSource`1 tcs, System.Func`2 endMethod, IAsyncResult l) [0x00000] in <filename unknown>:0
==> --- End of stack trace from previous location where exception was thrown ---
==> at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x00000] in <filename unknown>:0 ==> at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1+ConfiguredTaskAwaiter[System.Net.WebResponse].GetResult () [0x00000] in <filename unknown>:0
And my application is crashed. I tried to handle the application by using ExceptionEvent but i still cannot catch this exception.
Is there any suggestion to solve this problem? (It's very terrible that the application crashes each time the wifi disconnected).