mcs/class/Managed.Windows.Forms/System.Windows.Forms/MdiChildContext.cs

   1
   2 using System;
   3 using System.Drawing;
   4 using System.Drawing.Drawing2D;
   5
   6 namespace System.Windows.Forms {
   7
   8         internal class MdiChildContext {
   9
  10                 private static Color titlebar_color;
  11
  12                 private int BorderWidth = 3;
  13                 private int TitleBarHeight = 25;
  14                 private Size MinTitleBarSize = new Size (115, 25);
  15
  16                 private Form form;
  17                 private MdiClient mdi_container;
  18                 private Button close_button;
  19                 private Button maximize_button;
  20                 private Button minimize_button;
  21
  22                 // moving windows
  23                 private Point start;
  24                 private State state;
  25                 private FormPos sizing_edge;
  26                 private Rectangle virtual_position;
  27                 private Rectangle prev_virtual_position;
  28                 private Rectangle prev_bounds;
  29                 private bool maximized;
  30
  31                 private enum State {
  32                         Idle,
  33                         Moving,
  34                         Sizing,
  35                 }
  36
  37                 [Flags]
  38                 private enum FormPos {
  39                         None,
  40
  41                         TitleBar = 1,
  42
  43                         Top = 2,
  44                         Left = 4,
  45                         Right = 8,
  46                         Bottom = 16,
  47
  48                         TopLeft = Top | Left,
  49                         TopRight = Top | Right,
  50
  51                         BottomLeft = Bottom | Left,
  52                         BottomRight = Bottom | Right,
  53
  54                         AnyEdge = Top | Left | Right | Bottom,
  55                 }
  56
  57                 public MdiChildContext (Form form, MdiClient mdi_container)
  58                 {
  59                         titlebar_color = Color.FromArgb (255, 0, 0, 255);
  60                         this.form = form;
  61                         this.mdi_container = mdi_container;
  62
  63                         form.Paint += new PaintEventHandler (PaintWindowDecorations);
  64
  65                         minimize_button = new Button ();
  66                         minimize_button.Bounds = new Rectangle (form.Width - 62,
  67                                         BorderWidth + 2, 18, 22);
  68                         minimize_button.Anchor = AnchorStyles.Top | AnchorStyles.Right;
  69                         minimize_button.Paint += new PaintEventHandler (PaintButtonHandler);
  70                         minimize_button.Click += new EventHandler (OnMinimizeHandler);
  71
  72                         maximize_button = new Button ();
  73                         maximize_button.Bounds = new Rectangle (form.Width - 44,
  74                                         BorderWidth + 2, 18, 22);
  75                         maximize_button.Anchor = AnchorStyles.Top | AnchorStyles.Right;
  76                         maximize_button.Paint += new PaintEventHandler (PaintButtonHandler);
  77                         maximize_button.Click += new EventHandler (OnMaximizeHandler);
  78
  79                         close_button = new Button ();
  80                         close_button.Bounds = new Rectangle (form.Width - 24,
  81                                         BorderWidth + 2, 18, 22);
  82                         close_button.Anchor = AnchorStyles.Top | AnchorStyles.Right;
  83                         close_button.Paint += new PaintEventHandler (PaintButtonHandler);
  84                         close_button.Click += new EventHandler (CloseButtonClicked);
  85
  86                         form.Controls.AddImplicit (close_button);
  87                         form.Controls.AddImplicit (maximize_button);
  88                         form.Controls.AddImplicit (minimize_button);
  89                 }
  90
  91                 public bool HandleMessage (ref Message m)
  92                 {
  93                         switch ((Msg)m.Msg) {
  94
  95                         case Msg.WM_LBUTTONDOWN:
  96                                 return HandleLButtonDown (form, ref m);
  97
  98                         case Msg.WM_MOUSEMOVE:
  99                                 return HandleMouseMove (form, ref m);
 100
 101                         case Msg.WM_LBUTTONUP:
 102                                 HandleLButtonUp (ref m);
 103                                 break;
 104                         }
 105                         return false;
 106                 }
 107
 108
 109                 private bool HandleLButtonDown (Form form, ref Message m)
 110                 {
 111                         form.BringToFront ();
 112                         mdi_container.ActiveMdiChild = form;
 113
 114                         int x = Control.LowOrder ((int) m.LParam.ToInt32 ());
 115                         int y = Control.HighOrder ((int) m.LParam.ToInt32 ());
 116                         FormPos pos = FormPosForCoords (x, y);
 117
 118                         start = new Point (x, y);
 119                         virtual_position = form.Bounds;
 120
 121                         if (pos == FormPos.TitleBar) {
 122                                 HandleTitleBarDown (x, y);
 123                                 return true;
 124                         }
 125
 126                         if (IsSizable) {
 127                                 SetCursorForPos (pos);
 128
 129                                 if ((pos & FormPos.AnyEdge) == 0)
 130                                         return false;
 131
 132                                 state = State.Sizing;
 133                                 sizing_edge = pos;
 134                                 form.Capture = true;
 135                                 return true;
 136                         }
 137
 138                         return false;
 139                 }
 140
 141                 private void HandleTitleBarDown (int x, int y)
 142                 {
 143                         state = State.Moving;
 144                         form.Capture = true;
 145                 }
 146
 147                 private bool HandleMouseMove (Form form, ref Message m)
 148                 {
 149                         switch (state) {
 150                         case State.Moving:
 151                                 HandleWindowMove (m);
 152                                 return true;
 153                         case State.Sizing:
 154                                 HandleSizing (m);
 155                                 return true;
 156                         }
 157
 158                         if (IsSizable) {
 159                                 int x = Control.LowOrder ((int) m.LParam.ToInt32 ());
 160                                 int y = Control.HighOrder ((int) m.LParam.ToInt32 ());
 161                                 FormPos pos = FormPosForCoords (x, y);
 162
 163                                 SetCursorForPos (pos);
 164
 165                                 ClearVirtualPosition ();
 166                                 state = State.Idle;
 167                         }
 168
 169                         return false;
 170                 }
 171
 172                 private void SetCursorForPos (FormPos pos)
 173                 {
 174                         switch (pos) {
 175                         case FormPos.TopLeft:
 176                         case FormPos.BottomRight:
 177                                 form.Cursor = Cursors.SizeNWSE;
 178                                 break;
 179                         case FormPos.TopRight:
 180                         case FormPos.BottomLeft:
 181                                 form.Cursor = Cursors.SizeNESW;
 182                                 break;
 183                         case FormPos.Top:
 184                         case FormPos.Bottom:
 185                                 form.Cursor = Cursors.SizeNS;
 186                                 break;
 187                         case FormPos.Left:
 188                         case FormPos.Right:
 189                                 form.Cursor = Cursors.SizeWE;
 190                                 break;
 191                         default:
 192                                 form.Cursor = Cursors.Default;
 193                                 break;
 194                         }
 195                 }
 196
 197                 private void HandleWindowMove (Message m)
 198                 {
 199                         Point move = MouseMove (m);
 200
 201                         virtual_position.X = form.Left + move.X;
 202                         virtual_position.Y = form.Top + move.Y;
 203                         virtual_position.Width = form.Width;
 204                         virtual_position.Height = form.Height;
 205
 206                         DrawVirtualPosition ();
 207                 }
 208
 209                 private void HandleSizing (Message m)
 210                 {
 211                         Point move = MouseMove (m);
 212                         Rectangle pos = virtual_position;
 213                         int mw = MinTitleBarSize.Width + (BorderWidth * 2);
 214                         int mh = MinTitleBarSize.Height + (BorderWidth * 2);
 215
 216                         if ((sizing_edge & FormPos.Top) != 0) {
 217                                 int height = form.Height - move.Y;
 218                                 if (height <= mh) {
 219                                         move.Y += height - mh;
 220                                         height = mh;
 221                                 }
 222                                 pos.Y = form.Top + move.Y;
 223                                 pos.Height = height;
 224                         } else if ((sizing_edge & FormPos.Bottom) != 0) {
 225                                 int height = form.Height + move.Y;
 226                                 if (height <= mh)
 227                                         move.Y -= height - mh;
 228                                 pos.Height = form.Height + move.Y;
 229                         }
 230
 231                         if ((sizing_edge & FormPos.Left) != 0) {
 232                                 int width = form.Width - move.X;
 233                                 if (width <= mw) {
 234                                         move.X += width - mw;
 235                                         width = mw;
 236                                 }
 237                                 pos.X = form.Left + move.X;
 238                                 pos.Width = width;
 239                         } else if ((sizing_edge & FormPos.Right) != 0) {
 240                                 int width = form.Width + move.X;
 241                                 if (width <= mw)
 242                                         move.X -= width - mw;
 243                                 pos.Width = form.Width + move.X;
 244                         }
 245
 246                         UpdateVP (pos);
 247                 }
 248
 249                 private bool IsSizable {
 250                         get {
 251                                 switch (form.FormBorderStyle) {
 252                                 case FormBorderStyle.Sizable:
 253                                 case FormBorderStyle.SizableToolWindow:
 254                                         return true;
 255                                 default:
 256                                         return false;
 257                                 }
 258                         }
 259                 }
 260
 261                 private void UpdateVP (Rectangle r)
 262                 {
 263                         UpdateVP (r.X, r.Y, r.Width, r.Height);
 264                 }
 265
 266                 private void UpdateVP (Point loc, int w, int h)
 267                 {
 268                         UpdateVP (loc.X, loc.Y, w, h);
 269                 }
 270
 271                 private void UpdateVP (int x, int y, int w, int h)
 272                 {
 273                         virtual_position.X = x;
 274                         virtual_position.Y = y;
 275                         virtual_position.Width = w;
 276                         virtual_position.Height = h;
 277
 278                         DrawVirtualPosition ();
 279                 }
 280
 281                 private void HandleLButtonUp (ref Message m)
 282                 {
 283                         if (state == State.Idle)
 284                                 return;
 285
 286                         ClearVirtualPosition ();
 287
 288                         form.Capture = false;
 289                         form.Bounds = virtual_position;
 290                         state = State.Idle;
 291                 }
 292
 293                 private void PaintWindowDecorations (object sender, PaintEventArgs pe)
 294                 {
 295                         Color color = titlebar_color;
 296                         if (maximized)
 297                                 color = ThemeEngine.Current.ColorControl;
 298                         Rectangle tb = new Rectangle (BorderWidth, BorderWidth,
 299                                         form.Width - BorderWidth, TitleBarHeight);
 300
 301                         pe.Graphics.FillRectangle (ThemeEngine.Current.ResPool.GetSolidBrush (color),
 302                                                 BorderWidth, BorderWidth,
 303                                                 form.Width - BorderWidth, TitleBarHeight);
 304
 305                         tb.X += 18; // Room for the icon
 306                         if (form.Text != null) {
 307                                 StringFormat format = new StringFormat ();
 308                                 format.LineAlignment = StringAlignment.Center;
 309                                 pe.Graphics.DrawString (form.Text, form.Font,
 310                                                 ThemeEngine.Current.ResPool.GetSolidBrush (form.ForeColor),
 311                                                 tb, format);
 312                         }
 313
 314                         if (form.Icon != null) {
 315                                 pe.Graphics.DrawIcon (form.Icon, new Rectangle (BorderWidth + 2,
 316                                                                       BorderWidth + 2, 16, 16));
 317                         }
 318                 }
 319
 320                 private void PaintButtonHandler (object sender, PaintEventArgs pe)
 321                 {
 322                         if (sender == close_button) {
 323                                 ControlPaint.DrawCaptionButton (pe.Graphics,
 324                                                 close_button.ClientRectangle,
 325                                                 CaptionButton.Close,
 326                                                 close_button.ButtonState);
 327                         } else if (sender == maximize_button) {
 328                                 ControlPaint.DrawCaptionButton (pe.Graphics,
 329                                                 maximize_button.ClientRectangle,
 330                                                 CaptionButton.Maximize,
 331                                                 maximize_button.ButtonState);
 332                         } else if (sender == minimize_button) {
 333                                 ControlPaint.DrawCaptionButton (pe.Graphics,
 334                                                 minimize_button.ClientRectangle,
 335                                                 CaptionButton.Minimize,
 336                                                 minimize_button.ButtonState);
 337                         }
 338                 }
 339
 340                 private void CloseButtonClicked (object sender, EventArgs e)
 341                 {
 342                         form.Close ();
 343                         // form.Close should set visibility to false somewhere
 344                         // in it's closing chain but currently does not.
 345                         form.Visible = false;
 346                 }
 347
 348                 private void OnMinimizeHandler (object sender, EventArgs e)
 349                 {
 350                         form.SuspendLayout ();
 351                         form.Width = MinTitleBarSize.Width + (BorderWidth * 2);
 352                         form.Height = MinTitleBarSize.Height + (BorderWidth * 2);
 353                         form.ResumeLayout ();
 354                 }
 355
 356                 private void OnMaximizeHandler (object sender, EventArgs e)
 357                 {
 358                         if (maximized) {
 359                                 form.Bounds = prev_bounds;
 360                                 maximized = false;
 361                         } else {
 362                                 prev_bounds = form.Bounds;
 363                                 form.Bounds = form.Parent.Bounds;
 364                                 maximized = true;
 365                         }
 366                 }
 367
 368                 private Point NewLocation (Message m)
 369                 {
 370                         int x = Control.LowOrder ((int) m.LParam.ToInt32 ());
 371                         int y = Control.HighOrder ((int) m.LParam.ToInt32 ());
 372                         int x_move = x - start.X;
 373                         int y_move = y - start.Y;
 374
 375                         return new Point (form.Left + x_move, form.Top + y_move);
 376                 }
 377
 378                 private Point MouseMove (Message m)
 379                 {
 380                         int x = Control.LowOrder ((int) m.LParam.ToInt32 ());
 381                         int y = Control.HighOrder ((int) m.LParam.ToInt32 ());
 382                         int x_move = x - start.X;
 383                         int y_move = y - start.Y;
 384
 385                         return new Point (x_move, y_move);
 386                 }
 387
 388                 private void DrawVirtualPosition ()
 389                 {
 390                         ClearVirtualPosition ();
 391
 392                         XplatUI.DrawReversibleRectangle (mdi_container.Handle, virtual_position, 2);
 393                         prev_virtual_position = virtual_position;
 394                 }
 395
 396                 private void ClearVirtualPosition ()
 397                 {
 398                         if (prev_virtual_position != Rectangle.Empty)
 399                                 XplatUI.DrawReversibleRectangle (mdi_container.Handle,
 400                                                 prev_virtual_position, 2);
 401                         prev_virtual_position = Rectangle.Empty;
 402                 }
 403
 404                 private FormPos FormPosForCoords (int x, int y)
 405                 {
 406                         if (y < TitleBarHeight + BorderWidth) {
 407
 408                                 if (y > BorderWidth && x > BorderWidth &&
 409                                                 x < form.Width - BorderWidth)
 410                                         return FormPos.TitleBar;
 411
 412                                 if (x < BorderWidth || (x < 20 && y < BorderWidth))
 413                                         return FormPos.TopLeft;
 414
 415                                 if (x > form.Width - BorderWidth ||
 416                                         (x > form.Width - 20 && y < BorderWidth))
 417                                         return FormPos.TopRight;
 418
 419                                 if (y < BorderWidth)
 420                                         return FormPos.Top;
 421
 422                         } else if (y > form.Height - 20) {
 423
 424                                 if (x < BorderWidth ||
 425                                                 (x < 20 && y > form.Height - BorderWidth))
 426                                         return FormPos.BottomLeft;
 427
 428                                 if (x > form.Width - BorderWidth ||
 429                                                 (x > form.Width - 20 &&
 430                                                  y > form.Height - BorderWidth))
 431                                         return FormPos.BottomRight;
 432
 433                                 if (y > form.Height - BorderWidth)
 434                                         return FormPos.Bottom;
 435
 436
 437                         } else if (x < BorderWidth) {
 438                                 return FormPos.Left;
 439                         } else if (x > form.Width - BorderWidth) {
 440                                 return FormPos.Right;
 441                         }
 442
 443                         return FormPos.None;
 444                 }
 445         }
 446
 447 }
 448