source: tags/3.3.1/HeuristicLab.ExtLibs/HeuristicLab.WinFormsUI/2.3.1/WinFormsUI-2.3.1/Docking/DockPaneCaptionBase.cs

using System.Drawing;
using System.Security.Permissions;
using System.Windows.Forms;

namespace WeifenLuo.WinFormsUI.Docking {
  public abstract class DockPaneCaptionBase : Control {
    protected internal DockPaneCaptionBase(DockPane pane) {
      m_dockPane = pane;

      SetStyle(ControlStyles.OptimizedDoubleBuffer |
                ControlStyles.ResizeRedraw |
                ControlStyles.UserPaint |
                ControlStyles.AllPaintingInWmPaint, true);
      SetStyle(ControlStyles.Selectable, false);
    }

    private DockPane m_dockPane;
    protected DockPane DockPane {
      get { return m_dockPane; }
    }

    protected DockPane.AppearanceStyle Appearance {
      get { return DockPane.Appearance; }
    }

    protected bool HasTabPageContextMenu {
      get { return DockPane.HasTabPageContextMenu; }
    }

    protected void ShowTabPageContextMenu(Point position) {
      DockPane.ShowTabPageContextMenu(this, position);
    }

    protected override void OnMouseUp(MouseEventArgs e) {
      base.OnMouseUp(e);

      if (e.Button == MouseButtons.Right)
        ShowTabPageContextMenu(new Point(e.X, e.Y));
    }

    protected override void OnMouseDown(MouseEventArgs e) {
      base.OnMouseDown(e);

      if (e.Button == MouseButtons.Left &&
    DockPane.DockPanel.AllowEndUserDocking &&
          DockPane.AllowDockDragAndDrop &&
  !DockHelper.IsDockStateAutoHide(DockPane.DockState) &&
          DockPane.ActiveContent != null)
        DockPane.DockPanel.BeginDrag(DockPane);
    }

    [SecurityPermission(SecurityAction.LinkDemand, Flags = SecurityPermissionFlag.UnmanagedCode)]
    protected override void WndProc(ref Message m) {
      if (m.Msg == (int)Win32.Msgs.WM_LBUTTONDBLCLK) {
        if (DockHelper.IsDockStateAutoHide(DockPane.DockState)) {
          DockPane.DockPanel.ActiveAutoHideContent = null;
          return;
        }

        if (DockPane.IsFloat)
          DockPane.RestoreToPanel();
        else
          DockPane.Float();
      }
      base.WndProc(ref m);
    }

    internal void RefreshChanges() {
      if (IsDisposed)
        return;

      OnRefreshChanges();
    }

    protected virtual void OnRightToLeftLayoutChanged() {
    }

    protected virtual void OnRefreshChanges() {
    }

    protected internal abstract int MeasureHeight();
  }
}