C# user control as a custom panel

I create my own user control which only contains a panel : When I drag a myPanel object in the designer and then try to add a button on it, the button is in fact added to the form's controls. Is there a property/attribute I must set in order to perform this, an other way to do what I want ? ``` public class MyPanel : UserControl { private Panel panelMain; public MyPanel() { InitializeComponent(); } private void InitializeComponent() { this.panelMain = new System.Windows.Forms.Panel(); this.SuspendLayout(); // // panelMain // this.panelMain.BackColor = System.Drawing.SystemColors.ActiveCaption; this.panelMain.Dock = System.Windows.Forms.DockStyle.Fill; this.panelMain.Location = new System.Drawing.Point(0, 0); this.panelMain.Name = "panelMain"; this.panelMain.Size = new System.Drawing.Size(150, 150); this.panelMain.TabIndex = 0; // // myPanel // this.Controls.Add(this.panelMain); this.Name = "MyPanel"; this.ResumeLayout(false); } } ```