Changing GuiUnits based on ConfigNode.

[KspNoobUsernameTaken]

I've been trying to adapt the Beamed Power Standalone mod to manage a resource defined in a cfg file. I have this code: 

namespace BeamedPowerStandalone
{
    public class WirelessReceiver : PartModule
    {
        static ConfigNode setting = ConfigNode.Load(KSPUtil.ApplicationRootPath + "GameData/BeamedPowerStandalone/Settings.cfg");
        private static string ManagedResource = setting.GetValue("BPManagedResource");
        private static string ManagedResourceUnits = ManagedResource + "/s";
      OTHER STUFF HERE
      [KSPField(guiName = "Received Power", isPersistant = true, guiActive = true, guiActiveEditor = false, guiUnits = ManagedResourceUnits)]
	  public float ReceivedPower;
      OTHER STUFF HERE
    }
}

The important part is guiUnits = ManagedResourceUnits. It throws this error: 

Severity	Code	Description	Project	File	Line	Suppression State	Details
Error	CS0182	An attribute argument must be a constant expression, typeof expression or array creation expression of an attribute parameter type	

How do I fix this?

 

Code in this repository, VariableResourceBranch, if needed: https://github.com/ProgrammerFailure/BeamedPowerStandalone/tree/VariableResourceBranch

[HebaruSan]

What is ManagedResourceUnits?

[KspNoobUsernameTaken]

4 minutes ago, HebaruSan said:

What is ManagedResourceUnits?

Its supposed to be "whatever the resource being beamed is" followed by /s. So eg, if its electric charge, it would be electric charge/s

 

The idea is that the PAW of a part receiveing a resource will show: (transfer rate) (resource name) (/s)

Edited June 9 by KspNoobUsernameTaken

[HebaruSan]

No, how is it defined? What is it in the code?

[KspNoobUsernameTaken]

Just now, HebaruSan said:

No, how is it defined? What is it in the code?

The first instance of it shown above is the initialization; that is, ManagedResourceUnits is a private static string in the WirelessReceiver class. See here:

59 minutes ago, KspNoobUsernameTaken said:

private static string ManagedResourceUnits = ManagedResource + "/s";

So hopefully: 

Load configNode settings from file

set ManagedResource to Get value BPManagedResource

Set ManagedResourceUnits to ManagedResource + /s

[HebaruSan]

Try making it a const instead of static. A value passed to an attribute needs to be known at compile time.

[KspNoobUsernameTaken]

3 minutes ago, HebaruSan said:

Try making it a const instead of static. A value passed to an attribute needs to be known at compile time.

I tried it as const before and it worked, but thats an issue because I need to get the ManagedResource from a cfg file... I was dreading this would be the case. So there is actually no way to make it "dynamic"?

 

This is the same solution as: https://stackoverflow.com/questions/25859094/an-attribute-argument-must-be-a-constant-expression-create-an-attribute-of

Edited June 9 by KspNoobUsernameTaken

[HebaruSan]

You're not going to be able to pass a value from a config file into an [Attribute()], that just can't work based on how C# works. Attributes are a compile-time feature.

You could conceivably load the config file and then acquire a reference to the KSPField object and modify it at runtime, via  the Fields["ReceivedPower"] property on a given part module.

https://www.kerbalspaceprogram.com/ksp/api/class_k_s_p_field.html

[KspNoobUsernameTaken]

Just now, HebaruSan said:

You're not going to be able to pass a value from a config file into an [Attribute()], that just can't work based on how C# works. Attributes are a compile-time feature.

You could conceivably load the config file and then acquire a reference to the KSPField object and modify it at runtime, via  the Fields["ReceivedPower"] property on a given part module.

https://www.kerbalspaceprogram.com/ksp/api/class_k_s_p_field.html

I'll look into that later; for now I'll just make guiUnits = "/s", which will display (transfer rate) (/s). Thanks for the clarification. C# is really complicated for someone starting a week ago.