mcs/class/System.Web/System.Web.UI.WebControls/DataGridColumn.cs

   1 //
   2 // System.Web.UI.WebControls.DataGridColumn.cs
   3 //
   4 // Authors:
   5 //   Gaurav Vaish (gvaish@iitk.ac.in)
   6 //   Andreas Nahr (ClassDevelopment@A-SoftTech.com)
   7 //
   8 // (C) Gaurav Vaish (2002)
   9 // (C) 2003 Andreas Nahr
  10 //
  11
  12 //
  13 // Permission is hereby granted, free of charge, to any person obtaining
  14 // a copy of this software and associated documentation files (the
  15 // "Software"), to deal in the Software without restriction, including
  16 // without limitation the rights to use, copy, modify, merge, publish,
  17 // distribute, sublicense, and/or sell copies of the Software, and to
  18 // permit persons to whom the Software is furnished to do so, subject to
  19 // the following conditions:
  20 //
  21 // The above copyright notice and this permission notice shall be
  22 // included in all copies or substantial portions of the Software.
  23 //
  24 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  28 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  29 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  30 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  31 //
  32
  33 using System;
  34 using System.Web;
  35 using System.Web.UI;
  36 using System.ComponentModel;
  37
  38 namespace System.Web.UI.WebControls
  39 {
  40         [TypeConverter(typeof(ExpandableObjectConverter))]
  41         public abstract class DataGridColumn : IStateManager
  42         {
  43                 private StateBag viewState;
  44                 private bool     marked;
  45                 private TableItemStyle footerStyle;
  46                 private TableItemStyle headerStyle;
  47                 private TableItemStyle itemStyle;
  48
  49                 private DataGrid owner;
  50                 private bool     designMode;
  51
  52                 public DataGridColumn()
  53                 {
  54                         viewState = new StateBag();
  55                 }
  56
  57                 internal TableItemStyle FooterStyleInternal
  58                 {
  59                         get
  60                         {
  61                                 return footerStyle;
  62                         }
  63                 }
  64
  65                 internal TableItemStyle HeaderStyleInternal
  66                 {
  67                         get
  68                         {
  69                                 return headerStyle;
  70                         }
  71                 }
  72
  73                 internal TableItemStyle ItemStyleInternal
  74                 {
  75                         get
  76                         {
  77                                 return itemStyle;
  78                         }
  79                 }
  80
  81                 [DefaultValue (null), WebCategory ("Misc")]
  82                 [DesignerSerializationVisibility (DesignerSerializationVisibility.Content)]
  83                 [PersistenceMode (PersistenceMode.InnerProperty)]
  84                 [WebSysDescription ("The style applied to the footer of this column.")]
  85                 public virtual TableItemStyle FooterStyle
  86                 {
  87                         get
  88                         {
  89                                 if(footerStyle == null)
  90                                 {
  91                                         footerStyle = new TableItemStyle();
  92                                         if(IsTrackingViewState)
  93                                         {
  94                                                 footerStyle.TrackViewState();
  95                                         }
  96                                 }
  97                                 return footerStyle;
  98                         }
  99                 }
 100
 101                 [DefaultValue (null), WebCategory ("Misc")]
 102                 [DesignerSerializationVisibility (DesignerSerializationVisibility.Content)]
 103                 [PersistenceMode (PersistenceMode.InnerProperty)]
 104                 [WebSysDescription ("The style applied to the header of this column.")]
 105                 public virtual TableItemStyle HeaderStyle
 106                 {
 107                         get
 108                         {
 109                                 if(headerStyle == null)
 110                                 {
 111                                         headerStyle= new TableItemStyle();
 112                                         if(IsTrackingViewState)
 113                                         {
 114                                                 headerStyle.TrackViewState();
 115                                         }
 116                                 }
 117                                 return headerStyle;
 118                         }
 119                 }
 120
 121                 [DefaultValue (null), WebCategory ("Misc")]
 122                 [DesignerSerializationVisibility (DesignerSerializationVisibility.Content)]
 123                 [PersistenceMode (PersistenceMode.InnerProperty)]
 124                 [WebSysDescription ("The style applied to the rows of this column.")]
 125                 public virtual TableItemStyle ItemStyle
 126                 {
 127                         get
 128                         {
 129                                 if(itemStyle == null)
 130                                 {
 131                                         itemStyle = new TableItemStyle();
 132                                         if(IsTrackingViewState)
 133                                         {
 134                                                 itemStyle.TrackViewState();
 135                                         }
 136                                 }
 137                                 return itemStyle;
 138                         }
 139                 }
 140
 141                 [DefaultValue (""), WebCategory ("Misc")]
 142                 [WebSysDescription ("The text within the footer of this column.")]
 143                 public virtual string FooterText
 144                 {
 145                         get
 146                         {
 147                                 object o = ViewState["FooterText"];
 148                                 if(o != null)
 149                                 {
 150                                         return (string)o;
 151                                 }
 152                                 return String.Empty;
 153                         }
 154                         set
 155                         {
 156                                 ViewState["FooterText"] = value;
 157                                 OnColumnChanged();
 158                         }
 159                 }
 160
 161                 [DefaultValue (""), WebCategory ("Misc")]
 162                 [WebSysDescription ("The URL to an image that is displayed in the header of this column.")]
 163                 public virtual string HeaderImageUrl
 164                 {
 165                         get
 166                         {
 167                                 object o = ViewState["HeaderImageUrl"];
 168                                 if(o != null)
 169                                 {
 170                                         return (string)o;
 171                                 }
 172                                 return String.Empty;
 173                         }
 174                         set
 175                         {
 176                                 ViewState["HeaderImageUrl"] = value;
 177                                 OnColumnChanged();
 178                         }
 179                 }
 180
 181                 [DefaultValue (""), WebCategory ("Misc")]
 182                 [WebSysDescription ("The text within the header of this column.")]
 183                 public virtual string HeaderText
 184                 {
 185                         get
 186                         {
 187                                 object o = ViewState["HeaderText"];
 188                                 if(o != null)
 189                                 {
 190                                         return (string)o;
 191                                 }
 192                                 return String.Empty;
 193                         }
 194                         set
 195                         {
 196                                 ViewState["HeaderText"] = value;
 197                                 OnColumnChanged();
 198                         }
 199                 }
 200
 201                 [DefaultValue (""), WebCategory ("Misc")]
 202                 [WebSysDescription ("An expression that determines how the colum should be sorted.")]
 203                 public virtual string SortExpression
 204                 {
 205                         get
 206                         {
 207                                 object o = ViewState["SortExpression"];
 208                                 if(o != null)
 209                                 {
 210                                         return (string)o;
 211                                 }
 212                                 return String.Empty;
 213                         }
 214                         set
 215                         {
 216                                 ViewState["SortExpression"] = value;
 217                                 OnColumnChanged();
 218                         }
 219                 }
 220
 221                 [DefaultValue (true), WebCategory ("Misc")]
 222                 [WebSysDescription ("The visibility of this column.")]
 223                 public bool Visible
 224                 {
 225                         get
 226                         {
 227                                 object o = ViewState["Visible"];
 228                                 if(o != null)
 229                                 {
 230                                         return (bool)o;
 231                                 }
 232                                 return true;
 233                         }
 234                         set
 235                         {
 236                                 ViewState["Visible"] = value;
 237                                 OnColumnChanged();
 238                         }
 239                 }
 240
 241                 public virtual void Initialize()
 242                 {
 243                         if(owner != null && owner.Site != null)
 244                         {
 245                                 designMode = owner.Site.DesignMode;
 246                         }
 247                 }
 248
 249                 public virtual void InitializeCell(TableCell cell, int columnIndex, ListItemType itemType)
 250                 {
 251                         switch(itemType)
 252                         {
 253                                 case ListItemType.Header : InitializeCellHeader(cell, columnIndex);
 254                                                            break;
 255                                 case ListItemType.Footer : InitializeCellFooter(cell, columnIndex);
 256                                                            break;
 257                                 default                  : if (ItemStyleInternal != null)
 258                                                                 cell.ApplyStyle (ItemStyleInternal);
 259                                                            return;
 260                         }
 261                 }
 262
 263                 private void InitializeCellHeader(TableCell cell, int columnIndex)
 264                 {
 265                         WebControl ctrl = null;
 266                         bool       sort = true;
 267                         string     sortExpr = "";
 268                         ImageButton headButton;
 269                         Image       headImage;
 270                         LinkButtonInternal link;
 271
 272                         if(owner != null)
 273                         {
 274                                 sort = owner.AllowSorting;
 275                         }
 276                         if(sort)
 277                         {
 278                                 sortExpr = SortExpression;
 279                                 if(sortExpr.Length == 0)
 280                                 {
 281                                         sort = false;
 282                                 }
 283                         }
 284                         if(HeaderImageUrl.Length > 0)
 285                         {
 286                                 if(sort)
 287                                 {
 288                                         headButton = new ImageButton();
 289                                         headButton.ImageUrl = HeaderImageUrl;
 290                                         headButton.CommandName = "Sort";
 291                                         headButton.CommandArgument = sortExpr;
 292                                         headButton.CausesValidation = false;
 293                                         ctrl = headButton;
 294                                 } else
 295                                 {
 296                                         headImage = new Image();
 297                                         headImage.ImageUrl = HeaderImageUrl;
 298                                         ctrl = headImage;
 299                                 }
 300                         } else
 301                         {
 302                                 if(sort)
 303                                 {
 304                                         link = new LinkButtonInternal();
 305                                         link.Text = HeaderText;
 306                                         link.CommandName = "Sort";
 307                                         link.CommandArgument = sortExpr;
 308                                         link.CausesValidation = false;
 309                                         ctrl = link;
 310                                 } else
 311                                 {
 312                                         if(HeaderText.Length > 0)
 313                                         {
 314                                                 cell.Text = HeaderText;
 315                                         } else
 316                                         {
 317                                                 cell.Text = "&nbsp;";
 318                                         }
 319                                 }
 320                         }
 321                         if(ctrl != null)
 322                         {
 323                                 cell.Controls.Add(ctrl);
 324                         }
 325                         if (HeaderStyleInternal != null)
 326                                 cell.ApplyStyle (HeaderStyleInternal);
 327                 }
 328
 329                 private void InitializeCellFooter(TableCell cell, int columnIndex)
 330                 {
 331                         cell.Text = (FooterText.Length > 0 ? FooterText : "&nbsp;");
 332                         if (FooterStyleInternal != null)
 333                                 cell.ApplyStyle (FooterStyleInternal);
 334                 }
 335
 336                 public override string ToString()
 337                 {
 338                         return String.Empty;
 339                 }
 340
 341                 protected bool DesignMode
 342                 {
 343                         get
 344                         {
 345                                 return designMode;
 346                         }
 347                 }
 348
 349                 protected DataGrid Owner
 350                 {
 351                         get
 352                         {
 353                                 return owner;
 354                         }
 355                 }
 356
 357                 protected StateBag ViewState
 358                 {
 359                         get
 360                         {
 361                                 return viewState;
 362                         }
 363                 }
 364
 365                 /// <summary>
 366                 /// Undocumented
 367                 /// </summary>
 368                 protected virtual void OnColumnChanged()
 369                 {
 370                         if(owner != null)
 371                         {
 372                                 owner.OnColumnsChanged();
 373                         }
 374                 }
 375
 376                 internal void SetOwner (DataGrid datagrid)
 377                 {
 378                         owner = datagrid;
 379                 }
 380
 381                 protected virtual object SaveViewState()
 382                 {
 383                         object[] states = new object[4];
 384                         states[0] = ViewState.SaveViewState();
 385                         states[1] = (footerStyle == null ? null : footerStyle.SaveViewState());
 386                         states[2] = (headerStyle == null ? null : headerStyle.SaveViewState());
 387                         states[3] = (itemStyle == null ? null : itemStyle.SaveViewState());
 388
 389                         for (int i = 0; i < states.Length; i++) {
 390                                 if (states [i] != null)
 391                                         return states;
 392                         }
 393                         return null;
 394                 }
 395
 396                 protected virtual void LoadViewState(object savedState)
 397                 {
 398                         if (savedState == null)
 399                                 return;
 400
 401                         object[] states = (object[]) savedState;
 402                         ViewState.LoadViewState (states [0]);
 403                         FooterStyle.LoadViewState (states [1]);
 404                         HeaderStyle.LoadViewState (states [2]);
 405                         ItemStyle.LoadViewState (states [3]);
 406                 }
 407
 408                 protected virtual void TrackViewState()
 409                 {
 410                         marked = true;
 411                         ViewState.TrackViewState();
 412                         if(footerStyle != null)
 413                         {
 414                                 footerStyle.TrackViewState();
 415                         }
 416                         if(headerStyle != null)
 417                         {
 418                                 headerStyle.TrackViewState();
 419                         }
 420                         if(itemStyle != null)
 421                         {
 422                                 itemStyle.TrackViewState();
 423                         }
 424                 }
 425
 426                 protected bool IsTrackingViewState
 427                 {
 428                         get
 429                         {
 430                                 return marked;
 431                         }
 432                 }
 433
 434                 void IStateManager.LoadViewState(object savedState)
 435                 {
 436                         LoadViewState(savedState);
 437                 }
 438
 439                 object IStateManager.SaveViewState()
 440                 {
 441                         return SaveViewState();
 442                 }
 443
 444                 void IStateManager.TrackViewState()
 445                 {
 446                         TrackViewState();
 447                 }
 448
 449                 bool IStateManager.IsTrackingViewState
 450                 {
 451                         get
 452                         {
 453                                 return IsTrackingViewState;
 454                         }
 455                 }
 456         }
 457 }