Dynamic variables in C++ OOT for Gnu Radio 3.10

[Huang Wei]

Hello everyone,

In Gnu Radio 3.10, how to set a variable in a C++ OOT block that can be
adjusted dynamically by a QT GUI range?
I did in a .h file:
  Private:
    float _param;
  Public:
    void set_param(float param) {_param = param;}
and in the impl.cc file:
  _param = param;

anywhere else I need to change? I just tried before in Gnu Radio 3.7, and
now I am very lost with the new version.

Thank you very much.

Regards,
Wei