ESAPIX is an open source extension library for the Varian Eclipse Scripting API that contains extra methods, and bootstrapping frameworks to quickly develop applications for research and clinical use. It has no affiliation with Varian Medical Systems. It provides implementations for multithreading, asynchronous calls, debugging plugins, dependency injection, and view model "auto finding" through the Prism 6 library

To dive deeper, check out more examples and API documentation.

1. Create a new WPF project in Visual Studio.
2. Right click your project and select Manage NuGet Packages...
3. Search for "ESAPI" and select Install the most recent ESAPIX library for your install (eg. ESAPIX_13.6 for Aria 13.6)
4. Create two folders in your project :
   • Views
   • ViewModels
5. Right click the Views folder and select Add >> Window. Call it MainView.
6. Copy and paste this into the XAML file, but replace YOURPROJECTNAME with your project name

<Window x:Class="YOURPROJECTNAME.Views.MainView"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:ESAPIWPF.Views"
        mc:Ignorable="d"
        xmlns:prism="http://prismlibrary.com/"
        prism:ViewModelLocator.AutoWireViewModel="True"
        Title="MainView" Height="300" Width="300">
    <Grid>
        <TextBlock Text="{Binding ESAPITest}" FontSize="25"/>
    </Grid>
</Window>

7. Right click the ViewModels folder and select Add >> Class. Call it MainViewModel.
8. Copy and paste this into the MainViewModel file, but replace YOURPROJECTNAME with your project name

using ESAPIX.Facade.API;
using ESAPIX.Interfaces;
using Prism.Mvvm;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using W = System.Windows;

namespace YOURPROJECTNAME.ViewModels
{
    public class MainViewModel : BindableBase
    {
        private string esapiTest;
        private IScriptContext _ctx;

        public string ESAPITest
        {
            get { return esapiTest; }
            set { SetProperty(ref esapiTest, value); }
        }

        public MainViewModel(IScriptContext ctx)
        {
            _ctx = ctx;
            ctx.PatientChanged += Ctx_PatientChanged;
        }

        private void Ctx_PatientChanged(Patient newPatient)
        {
            if (newPatient != null)
            {
                var plans = newPatient.Courses.SelectMany(c => c.PlanSetups).Count();
                ESAPITest = $"{newPatient?.LastName}, {newPatient?.FirstName} | {plans} Plans!";
            }
        }
    }
}

9. Open the App.xaml file, and remove the * StartupUri="MainWindow"* at the top.
10. Open up the App.cs file and replace the App class with this:

    /// <summary>
    /// Interaction logic for App.xaml
    /// </summary>
    public partial class App : Application
    {
        string USERNAME = "";
        string PASSWORD = "";

        protected override void OnStartup(StartupEventArgs e)
        {
            base.OnStartup(e);
            VMSLink.VMSLinker.Run(); //For facade to link up
            var bs = new ESAPIX.AppKit.AppBootstrapper<MainView>(USERNAME, PASSWORD);
            bs.Run();
        }
    }

So far we haven't actually wired up the Varian classes. You could build and play with your app at this stage, but it won't connect to real Varian data. To link it up, we will create one extra tiny project in the same solution. We are doing this to have a separation of VMS data with application development. This makes it easier to test your application, use in unit tests, and do cool multithreaded stuff.

1. Right click your solution file and select **Add >> New Project **
2. Select Class Library as the type, and name it VMS Link (this doesn't matter except that's what we named it in the code above)
3. Add the NuGet Package ESAPIX_Bootstrapper_{version} by searching again for "ESAPI" in Manage NuGet Packages
4. Add a class called VMSLinker to this project and paste this code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace VMSLink
{
    public class VMSLinker
    {
        public static void Run()
        {
            ESAPIX.Bootstrapper.FacadeInitializer.Initialize();
        }
    }
}

5. Right click your original project References, select Add Reference and click VMSLink in the project tab
6. Run your project!