Xamarin UI Thread blocks deadlock – UI Stuck while calling Async

UI Blocking Code

public static async Task<JObject> GetJsonAsync(Uri uri)
{
  using (var client = new HttpClient())
  {
    var jsonString = await client.GetStringAsync(uri);
    return JObject.Parse(jsonString);
  }
}
Preventing the Deadlock
public static async Task<JObject> GetJsonAsync(Uri uri)
{
  using (var client = new HttpClient())
  {
    var jsonString = await client.GetStringAsync(uri).ConfigureAwait(false);
    return JObject.Parse(jsonString);
  }
} Using ConfigureAwait(false) to avoid deadlocks is a dangerous practice. You would have to use ConfigureAwait(false) for every await in the transitive closure of all methods called by the blocking code, including all third- and second-party code.
 

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