I was able to solve the connection problem, I'm using MysqlHandler and
the way to solve it was by setting <uses-sdk android: minSdkVersion = "4" android: targetSdkVersion = "4" /> although I'm not happy because I do not see the reason why I have to set targetSdkVersion = "4"
Do you think I can clarify if I can use the mysql library with MysqlHandler?
the problem is that when i put it on android: targetSdkVersion = "26" /> the program does not establish the connection with my mysql server "Connection error"
the way to solve it was by setting <uses-sdk android: minSdkVersion = "4" android: targetSdkVersion = "4" /> although I'm not happy because I do not see the reason why I have to set targetSdkVersion = "4"
You do realize you are using a library that is over 5 years old and has not been updated since then. It is not a standard library that comes with B4A, it is a user contributed library. So yeah, with such an old library, targetSdkVersion = "4" may be necessary.