At the early of this year, I visited Japan. I saw a Pepper Robot in the mall. I tried to talk with him in English. I do not think he can understand. But when I tried to shake hand with him, he can understand and shake hand with me. That is cute. I think his AI can read human gestures.

After I installed Facebook SDK for Andorid. I found I cannot deploy my app in the debug anymore. I clicked the play button in Visual Studio, no compilation errors at all. Visual Studio is only freezed in "Deploying in [Phone Name]" for a little white. Then it stoped and gave out this error message,'Exception in thread "main"'. After I did a number of random search in Google, I found some people in the Xamarin Forum mentioned they need to increase the heap size to 1G after installing Facebook SDK. Finally, I increased the heap size to 1G in (Project Properties -> Android Options->Advanced-> Java Max Heap Size). Then it works!

When you use Windows 8.1 or older, you wish to synchronize your folders with Sharepoint Online or Onedrive for Business. You need to download a plug-in call "Onedrive for Business". Moreover, you need to put the SharePoint or OneDrive URL manually. In Windows 10, that is easy! All you need to do, going to the folders you wish to synchronize in Sharepoint or Onedrive in your browser. Then you can see a "Sync" in the toolbar. Then you need to click; then Windows will synchronize the folder. You will see the folder in your file explorer too. No software is required to install and I tried that works in Edge and Chrome!

After I switched my Xamarin Forms app from Normal Form Activity to FormsAppCompatActivity. This can provide more function in Material Design, such as TextInputLayout. But I got this error:System.MissingMethodException: Method 'Android.Support.V4.Widget.DrawerLayout.AddDrawerListener' not found. I found the problem is from the libraries. After I updated the latest Xamarin Forms Library in Android Project. That works!

I got an error when I built my application. The error said 'No xmlns declaration for prefix "local". Because I used the xaml, I found the compiler did not check the error in xaml file. As a result, it got the runtime error like. This is very easy to solve. Please search all xaml files you used local has this xmlns:local="clr-namespace:[your namespace]"