Is possible to Make C# component respond to keypress?

Grasshopper Developer
1

i am writing a c# component in visual studio.
And have one question :
When this c# component is selected ,then i press “p” in keyboard to toggle the preview of this component, how to write respond to this keypress event?

Thank you!

2

This might not be exactly what you’re looking for but are you aware of the customizable shortcuts in the Grasshopper Settings?

image
image1227×1044 121 KB

4

Thank you,but i just for example by using preview,the real thing i donot know is how to write c# to respond keypress.

5 
public class KeyListenerExampleComponent : GH_Component
{
    private bool _listen;
    private bool _expired;
    private Keys _key;
    private bool _isPressed;
    public KeyListenerExampleComponent() : base("Key Listener", "KL", "Description", "Extra", "Examples")
    {
        _listen = false;
        _expired = true;
        _key = Keys.F7;
        _isPressed = false;
    }
    public override void AddedToDocument(GH_Document document)
    {
        if (Locked) RemoveHandlers();
        else AddHandlers();
    }
    public override void RemovedFromDocument(GH_Document document) => RemoveHandlers();
    public override void DocumentContextChanged(GH_Document document, GH_DocumentContext context)
    {
        switch (context)
        {
            case GH_DocumentContext.Open:
            case GH_DocumentContext.Loaded:
            case GH_DocumentContext.Unlock:
                if (Locked)
                {
                    RemoveHandlers();
                    break;
                }

                AddHandlers();
                break;
            case GH_DocumentContext.Close:
            case GH_DocumentContext.Unloaded:
            case GH_DocumentContext.Lock:
                RemoveHandlers();
                break;
        }
    }
    public override void ExpireSolution(bool recompute)
    {
        _expired = true;
        base.ExpireSolution(recompute);
    }
    private void AddHandlers()
    {
        RemoveHandlers();
        Instances.DocumentEditor.KeyDown += KeyDownEventHandler;
        Instances.DocumentEditor.KeyUp += KeyUpEventHandler;
    }
    private void RemoveHandlers()
    {
        Instances.DocumentEditor.KeyDown -= KeyDownEventHandler;
        Instances.DocumentEditor.KeyUp -= KeyUpEventHandler;
    }
    private void KeyDownEventHandler(object sender, KeyEventArgs e)
    {
        if (!_listen || _expired || !Equals(e.KeyCode, _key)) return;
        _isPressed = true;
        ExpireSolution(true);
    }
    private void KeyUpEventHandler(object sender, KeyEventArgs e)
    {
        if (!_listen || _expired || !Equals(e.KeyCode, _key)) return;
        _isPressed = false;
        ExpireSolution(true);
    }

    protected override void RegisterInputParams(GH_InputParamManager pManager)
    {
        pManager.AddTextParameter("Key", "Key", "Key", GH_ParamAccess.item, "F7");
        pManager.AddBooleanParameter("Listen", "Listen", "Listen", GH_ParamAccess.item, false);
    }

    protected override void RegisterOutputParams(GH_OutputParamManager pManager)
    {
        pManager.AddBooleanParameter("IsPressed", "IsPressed", "IsPressed", GH_ParamAccess.item);
    }
    protected override void SolveInstance(IGH_DataAccess da)
    {
        var key = "F7";
        da.GetData(0, ref key);
        TryParse(key, out _key);
        da.GetData(1, ref _listen);
        _expired = false;
        da.SetData(0, _isPressed);
    }
    public override Guid ComponentGuid => new Guid("690c3f25-0e14-4d11-922e-afcf2cdc3e5b");
}


KeyListenerExample.zip (102.6 KB)

5 Likes
6

Thank you very much,i will try it