• Posted on Jul 29, 2023
• 1 min read

🤖 AI summary: This article outlines a method for preventing default error messages in Basic4Android WebViews by verifying internet connectivity before loading content. By utilizing the Network library and initializing a ServerSocket on port 0, developers can implement a subroutine that checks the device's IP address. If the returned IP is "127.0.0.1", the device is considered offline, while any other IP indicates an active connection. This boolean check allows the application to gracefully handle offline states by displaying custom messages or hiding the WebView instead of showing standard browser errors.

Basic4Android lets you use WebView to load URLs in your application, but if your phone isn’t connected to the internet when the program runs, an error message will show up in the WebView itself, which doesn’t look nice.

By using this piece of code, you can check if the user’s phone is connected to the internet or not. Depending on the information you get, you can either hide the WebView or display an error message. Of course, this code can have other applications as well, but in this post, I’m using it for this purpose.

Required libraries: Network

First you need to define a ServerSocket variable in Process_Globals:

Sub Process_Globals
    Dim server As ServerSocket
End Sub

Then, check the phone’s IP address using the following Sub:

Sub GetIp As Boolean
    server.Initialize(0,"")
    If server.GetMyIP = "127.0.0.1" Then
      Return False
    Else
      Return True
    End If
End Sub

As you know, if we’re not connected to the internet, the default IP address of the device is 127.0.0.1. The If condition checks this IP and returns False if the phone’s IP matches 127.0.0.1 and if the IP address is not 127.0.0.1 (meaning we are connected to the internet), it returns True.

By the way, the number 0 in server.Initialize(0,"") represents the port number. More Info

Last but not least, you can use the True or False value to check if the internet connection is working:

If GetIp=True Then
  ToastMessageShow("Internet connection is established.", False)
Else
  ToastMessageShow("No internet connection!", False)
End If

That’s all!

Happy coding :D