I think that bei using ModelicaReference.Annotations.choices can do what i want, selecting model via the GUI. so I change my code.
according to the documentation, when annotation(choices(choice(redaclare bla bla))) be added to the code, there will be a selection list in the GUI. but it dosen't work.
could someone give me a example for how to use annotation.example? I tryed the example in https://build.openmodelica.org/Document … oices.html  but it dosen't work either
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  model Model_P
    package Medium = Modelica.Media.R134a.R134a_ph;
    parameter Modelica.SIunits.AbsolutePressure p;
    Medium.ThermodynamicState state;
  equation

  end Model_P;
  model Model_PT
    extends Test_Selection.Model_P;
 
  parameter Modelica.SIunits.Temperature T;
  equation
    state = Medium.setState_pTX(p, T);
  end Model_PT;

  model Model_PH
    extends Test_Selection.Model_P;
    parameter Modelica.SIunits.Enthalpy h;
 
  equation
    state = Medium.setState_phX(p,h);
  end Model_PH;

  model selectModel
    replaceable Model_PT model_final(p = p, T=secondInput) annotation(choices(
    choice(redeclare Model_PH model_final(p=p, h= secondInput))));
    parameter Modelica.SIunits.AbsolutePressure p;
    parameter Real secondInput = 0;
  end selectModel;
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That is because we do not have support for redeclares in the GUI yet.
Is work in progress to be part of 1.15 soon.

thanks, so is the model selection through GUI also not possible in 1.14?
as my first post, I want to creat a Model, which select submodel to be used via Boolean parameter. Is it also not possible? 

I supose that there is a good reason for not using a solution as simple as a direct selection. For the GUI input, it is not possible to have the parameters defined at the base level of the model, but yes those defined in objects inside the model. So the solution is to crate a separate model with the parameters you need as inputs, create an instance inside your model, and make equal the value of the parameters, or use directly those inside the GUI. I would sugest something like this:

package Test_Selection
  model GUI
    parameter Modelica.SIunits.AbsolutePressure p;
    parameter Modelica.SIunits.Temperature T;
    parameter Modelica.SIunits.Enthalpy h;
    parameter Boolean useT=true;
annotation(
        Diagram,
        Icon(graphics = {Text(origin = {-5, -67}, extent = {{105, -23}, {-93, 11}}, textString = "Use p,T: %useT"), Text(origin = {-5, 77}, extent = {{105, -23}, {-93, 11}}, textString = "p: %p"), Text(origin = {-7, 27}, extent = {{105, -23}, {-93, 11}}, textString = "T: %T"), Text(origin = {-7, -21}, extent = {{105, -23}, {-93, 11}}, textString = "h: %h")}));
  end GUI;
 
  model SelectModel2
    package Medium = Modelica.Media.R134a.R134a_ph;
    parameter Modelica.SIunits.AbsolutePressure p=gui.p;
    parameter Modelica.SIunits.Temperature T=gui.T;
    parameter Modelica.SIunits.Enthalpy h=gui.h;
    parameter Boolean useT=gui.useT "if made false enthalpy will be used";
    Medium.ThermodynamicState state;
    FreeFluids.Various.Test_Selection.GUI gui(T = 223.15, h = 1e5, p = 500000, useT = false)  annotation(
        Placement(visible = true, transformation(origin = {1, 1}, extent = {{-17, -17}, {17, 17}}, rotation = 0)));
  equation
    if useT then
      state=Medium.setState_pTX(p,T);
    else
      state=Medium.setState_phX(p,h);
    end if;
  end SelectModel2;
end Test_Selection;