Wsrtjtyk

OK I have a custom Circular Button that I extended from Button class. See Below:

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Drawing.Drawing2D;

using System.Linq;

using System.Text;

using System.Windows.Forms;

using System.Drawing;



namespace CircleButton

{



public class CircleButton : Button

{

    private Color _fillColor = Color.Red;

    private Color _hoverColor = Color.Blue;





    [Category("Custom")]

    [Browsable(true)]

    [Description("Sets the fill color of the round button")]

    [Editor(typeof(System.Windows.Forms.Design.WindowsFormsComponentEditor), typeof(System.Drawing.Color))]

   public Color FillColor

    {

        set

        {

            this._fillColor = value;



        }

        get

        {

            return this._fillColor;



        }

    }



    [Category("Custom")]

    [Browsable(true)]

    [Description("Sets the Hover color of the round button")]

    [Editor(typeof(System.Windows.Forms.Design.WindowsFormsComponentEditor), typeof(System.Drawing.Color))]

    public Color HoverColor

    {

        set

        {

            this._hoverColor = value;





        }

        get

        {

            return this._hoverColor;

        }

    }





    protected override void OnPaint(PaintEventArgs pevent)

    {

        GraphicsPath gp = new GraphicsPath();

        gp.AddEllipse(0, 0, ClientSize.Width, ClientSize.Height);

        this.Region = new System.Drawing.Region(gp);

        base.OnPaint(pevent);

    }



    protected override void OnCreateControl()

    {

        this.FlatAppearance.MouseOverBackColor = this._hoverColor;

        this.FlatAppearance.BorderSize = 0;

        this.BackColor = this._fillColor;

        this.FlatStyle = FlatStyle.Flat;

        base.OnCreateControl();

    }  

}

Everthing works great in the Visual Studio Designer, but when I select the FillColor and HoverColor properties during design time, the colors on the design time control do not update.

Keep in mind that the colors DO show the appropriate change during runtime.

Maybe I am missing another directive or something? I have searched but unable to come up with an answer. I have spent 2 days on this.

This control is going to be distributed to another designer and needs to work properly during design time.

Any help would be most appreciated.

I recommend reading these articles:

• Creating a Windows Forms Control That Takes Advantage of Visual Studio Design-Time Features


• Whats the difference between Control.Invalidate, Control.Update and Control.Refresh?

In short, you need to call Invalidate() in your property setters, as this triggers an eventual repaint (repaints are not immediate: a repaint request actually queues-up a repaint, so if two or more properties are set then the control will still only be repainted once (this is why UI properties must be set in the UI thread).

You should also perform equality checks in property setters to prevent unnecessary repainting, like so:

[Category("Custom")]

[Browsable(true)]

[Description("Sets the Hover color of the round button")]

[Editor(typeof(System.Windows.Forms.Design.WindowsFormsComponentEditor), typeof(System.Drawing.Color))]

public Color HoverColor

{

    get

    {

        return this._hoverColor;

    }

    set

    {

        if( this._hoverColor != value )

        {

            this._hoverColor = value;

            this.Invalidate();

        } 

    }

}

(Style-tip: In recent years the C# developer ecosystem (and Microsoft too) have started to use _underscore-prefixed identifiers only for static fields and normal camelCase for instance fields, but always accessed with this., so I would change this._hoverColor to this.hoverColor).

Ok so I finally solved it by changing the property in the setter, while adding the Invalidate() Method:

if (this._fillColor != value)

            {

                this._fillColor = value;

                this.BackColor = this._fillColor;  ///<--Added this line worked

                this.Invalidate();

            }

Thank you for your great suggestions and answers, I truly appreciate your help!