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

   1 //
   2 // System.Web.UI.WebControls.Repeater.cs
   3 //
   4 // Authors:
   5 //      Ben Maurer (bmaurer@novell.com)
   6 //
   7 // (C) 2005 Novell, Inc (http://www.novell.com)
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28
  29 // Helpful resources while implementing this class:
  30 //
  31 // _Developing Microsoft ASP.NET Server Controls and Components_ (Kothari, Datye)
  32 //    Chapters 16 and 20 (especially listing 20-3 on page 559)
  33 //
  34 // "Building DataBound Templated Custom ASP.NET Server Controls" (Mitchell) on MSDN
  35 //    Right now, http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnaspp/html/databoundtemplatedcontrols.asp
  36 //    works, but with msdn we all know that urls have a very short lifetime :-)
  37 //
  38
  39 using System.Collections;
  40 using System.ComponentModel;
  41 using System.Security.Permissions;
  42 using System.Web.Util;
  43
  44 namespace System.Web.UI.WebControls {
  45
  46         // CAS
  47         [AspNetHostingPermission (SecurityAction.LinkDemand, Level = AspNetHostingPermissionLevel.Minimal)]
  48         [AspNetHostingPermission (SecurityAction.InheritanceDemand, Level = AspNetHostingPermissionLevel.Minimal)]
  49         // attributes
  50         [DefaultEvent ("ItemCommand")]
  51         [DefaultProperty ("DataSource")]
  52         [Designer ("System.Web.UI.Design.WebControls.RepeaterDesigner, " + Consts.AssemblySystem_Design, "System.ComponentModel.Design.IDesigner")]
  53         [ParseChildren (true)]
  54         [PersistChildren (false)]
  55         public class Repeater : Control, INamingContainer
  56         {
  57                 object dataSource;
  58                 IDataSource boundDataSource;
  59                 bool initialized;
  60                 bool preRendered = false;
  61                 bool requiresDataBinding;
  62                 DataSourceSelectArguments selectArguments;
  63                 IEnumerable data;
  64
  65                 // See Kothari, listing 20-3
  66                 protected internal
  67                 override void CreateChildControls ()
  68                 {
  69                         // We are recreating the children from viewstate
  70                         Controls.Clear();
  71
  72                         // Build the children from the viewstate
  73                         if (ViewState ["Items"] != null)
  74                                 CreateControlHierarchy (false);
  75                 }
  76
  77                 // See Kothari, listing 20-3
  78                 protected override void OnDataBinding (EventArgs e)
  79                 {
  80                         base.OnDataBinding (EventArgs.Empty);
  81
  82                         Controls.Clear ();
  83                         ClearChildViewState ();
  84                         TrackViewState ();
  85
  86                         CreateControlHierarchy (true);
  87
  88                         ChildControlsCreated = true;
  89                 }
  90
  91                 void DoItem (int i, ListItemType t, object d, bool databind)
  92                 {
  93                         RepeaterItem itm = CreateItem (i, t);
  94
  95                         if (t == ListItemType.Item || t == ListItemType.AlternatingItem)
  96                                 items.Add (itm);
  97
  98                         itm.DataItem = d;
  99                         RepeaterItemEventArgs e = new RepeaterItemEventArgs (itm);
 100                         InitializeItem (itm);
 101
 102                         //
 103                         // It is very important that this be called *before* data
 104                         // binding. Otherwise, we won't save our state in the viewstate.
 105                         //
 106                         Controls.Add (itm);
 107                         OnItemCreated (e);
 108
 109                         if (databind) {
 110                                 itm.DataBind ();
 111                                 OnItemDataBound (e);
 112                         }
 113                 }
 114
 115                 protected virtual void CreateControlHierarchy (bool useDataSource)
 116                 {
 117                         IEnumerable ds;
 118                         items = new ArrayList ();
 119                         itemscol = null;
 120
 121                         if (useDataSource) {
 122                                 ds = GetData ();
 123                         }
 124                         else {
 125                                 // Optimize (shouldn't need all this memory ;-)
 126                                 ds = new object [(int) ViewState ["Items"]];
 127                         }
 128
 129                         // If there is no datasource, then we don't show anything. the "Items"
 130                         // viewstate won't get set, so on postback, we won't get here
 131                         if (ds == null)
 132                                 return;
 133
 134                         if (HeaderTemplate != null)
 135                                 DoItem (-1, ListItemType.Header, null, useDataSource);
 136
 137                         int idx = 0;
 138                         foreach (object o in ds) {
 139                                 if (idx != 0 && SeparatorTemplate != null)
 140                                         DoItem (idx - 1, ListItemType.Separator, null, useDataSource);
 141
 142                                 DoItem (idx, idx % 2 == 0 ? ListItemType.Item : ListItemType.AlternatingItem, o, useDataSource);
 143                                 idx ++;
 144                         }
 145
 146                         if (FooterTemplate != null)
 147                                 DoItem (-1, ListItemType.Footer, null, useDataSource);
 148
 149                         ViewState ["Items"] = idx;
 150                 }
 151
 152                 // Why does this get overriden?
 153                 public override void DataBind ()
 154                 {
 155                         // In all the examples I've seen online, this does base.OnDataBinding and
 156                         // then does all the create child controls stuff. But from stack traces on
 157                         // windows, this doesn't seem to be the case here.
 158                         OnDataBinding (EventArgs.Empty);
 159
 160                         RequiresDataBinding = false;
 161                 }
 162
 163                 protected virtual RepeaterItem CreateItem (int itemIndex, ListItemType itemType)
 164                 {
 165                         return new RepeaterItem (itemIndex, itemType);
 166                 }
 167
 168                 protected virtual void InitializeItem (RepeaterItem item)
 169                 {
 170                         ITemplate t = null;
 171
 172                         switch (item.ItemType) {
 173                         case ListItemType.Header:
 174                                 t = HeaderTemplate;
 175                                 break;
 176                         case ListItemType.Footer:
 177                                 t = FooterTemplate;
 178                                 break;
 179                         case ListItemType.Item:
 180                                 t = ItemTemplate;
 181                                 break;
 182                         case ListItemType.AlternatingItem:
 183                                 t = AlternatingItemTemplate;
 184                                 if (t == null)
 185                                         t = ItemTemplate;
 186                                 break;
 187                         case ListItemType.Separator:
 188                                 t = SeparatorTemplate;
 189                                 break;
 190                         }
 191
 192                         if (t != null)
 193                                 t.InstantiateIn (item);
 194                 }
 195
 196
 197                 protected override bool OnBubbleEvent (object sender, EventArgs e)
 198                 {
 199                         RepeaterCommandEventArgs rcea = e as RepeaterCommandEventArgs;
 200                         if (rcea != null) {
 201                                 OnItemCommand (rcea);
 202                                 return true;
 203                         }
 204
 205                         return false;
 206                 }
 207
 208
 209                 public override ControlCollection Controls {
 210                         get {
 211                                 EnsureChildControls ();
 212                                 return base.Controls;
 213                         }
 214
 215                 }
 216
 217                 RepeaterItemCollection itemscol;
 218                 ArrayList items;
 219                 [Browsable(false)]
 220                 [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
 221                 [WebSysDescription ("")]
 222                 public virtual RepeaterItemCollection Items {
 223                         get {
 224                                 if (itemscol == null) {
 225                                         if (items == null)
 226                                                 items = new ArrayList ();
 227
 228                                         itemscol = new RepeaterItemCollection (items);
 229                                 }
 230                                 return itemscol;
 231                         }
 232                 }
 233
 234                 [DefaultValue("")]
 235                 [WebSysDescription ("")]
 236                 [WebCategory ("Data")]
 237                 public virtual string DataMember {
 238                         get {
 239                                 return ViewState.GetString ("DataMember", "");
 240                         }
 241                         set {
 242                                 if (value == null)
 243                                         ViewState.Remove ("DataMember");
 244                                 else
 245                                         ViewState ["DataMember"] = value;
 246
 247                                 if (!Initialized)
 248                                         OnDataPropertyChanged ();
 249                         }
 250                 }
 251
 252                 [Bindable(true)]
 253                 [DefaultValue(null)]
 254                 [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
 255                 [WebSysDescription ("")]
 256                 [WebCategory ("Data")]
 257                 public virtual object DataSource {
 258                         get {
 259                                 return dataSource;
 260                         }
 261
 262                         set {
 263                                 if (value == null || value is IListSource || value is IEnumerable) {
 264 // FIXME - can't duplicate in a test case ? LAMESPEC ?
 265 // can't duplicate in a test case
 266 //                                      if ((dataSourceId != null) && (dataSourceId.Length != 0))
 267 //                                              throw new HttpException (Locale.GetText ("DataSourceID is already set."));
 268
 269                                         dataSource = value;
 270
 271                                         if (!Initialized)
 272                                                 OnDataPropertyChanged ();
 273                                 } else
 274                                         throw new ArgumentException (String.Format (
 275                                             "An invalid data source is being used for {0}. A valid data source must implement either IListSource or IEnumerable",
 276                                             ID));
 277                         }
 278                 }
 279
 280                 [DefaultValue ("")]
 281                 [IDReferenceProperty (typeof (DataSourceControl))]
 282                 public virtual string DataSourceID
 283                 {
 284                         get {
 285                                 return ViewState.GetString ("DataSourceID", "");
 286                         }
 287                         set {
 288                                 if (dataSource != null)
 289                                         throw new HttpException ("Only one of DataSource and DataSourceID can be specified.");
 290                                 ViewState ["DataSourceID"] = value;
 291
 292                                 if (!Initialized)
 293                                         OnDataPropertyChanged ();
 294                         }
 295                 }
 296
 297                 [Browsable (true)]
 298                 public override bool EnableTheming {
 299                         get { return base.EnableTheming; }
 300                         set { base.EnableTheming = value; }
 301                 }
 302
 303                 ITemplate alt_itm_tmpl;
 304                 [Browsable(false)]
 305                 [DefaultValue(null)]
 306                 [PersistenceMode(PersistenceMode.InnerProperty)]
 307                 [TemplateContainer (typeof (RepeaterItem))]
 308                 [WebSysDescription ("")]
 309                 public virtual ITemplate AlternatingItemTemplate {
 310                         get {
 311                                 return alt_itm_tmpl;
 312                         }
 313                         set {
 314                                 alt_itm_tmpl = value;
 315                         }
 316                 }
 317
 318                 ITemplate footer_tmpl;
 319                 [Browsable(false)]
 320                 [DefaultValue(null)]
 321                 [PersistenceMode(PersistenceMode.InnerProperty)]
 322                 [TemplateContainer (typeof (RepeaterItem))]
 323                 [WebSysDescription ("")]
 324                 public virtual ITemplate FooterTemplate {
 325                         get {
 326                                 return footer_tmpl;
 327                         }
 328                         set {
 329                                 footer_tmpl = value;
 330                         }
 331                 }
 332
 333                 ITemplate header_tmpl;
 334                 [Browsable(false)]
 335                 [DefaultValue(null)]
 336                 [PersistenceMode(PersistenceMode.InnerProperty)]
 337                 [TemplateContainer (typeof (RepeaterItem))]
 338                 [WebSysDescription ("")]
 339                 public virtual ITemplate HeaderTemplate {
 340                         get {
 341                                 return header_tmpl;
 342                         }
 343                         set {
 344                                 header_tmpl = value;
 345                         }
 346                 }
 347
 348                 ITemplate item_tmpl;
 349                 [Browsable(false)]
 350                 [DefaultValue(null)]
 351                 [PersistenceMode(PersistenceMode.InnerProperty)]
 352                 [TemplateContainer (typeof (RepeaterItem))]
 353                 [WebSysDescription ("")]
 354                 public virtual ITemplate ItemTemplate {
 355                         get {
 356                                 return item_tmpl;
 357                         }
 358                         set {
 359                                 item_tmpl = value;
 360                         }
 361                 }
 362
 363                 ITemplate separator_tmpl;
 364                 [Browsable(false)]
 365                 [DefaultValue(null)]
 366                 [PersistenceMode(PersistenceMode.InnerProperty)]
 367                 [TemplateContainer (typeof (RepeaterItem))]
 368                 [WebSysDescription ("")]
 369                 public virtual ITemplate SeparatorTemplate {
 370                         get {
 371                                 return separator_tmpl;
 372                         }
 373                         set {
 374                                 separator_tmpl = value;
 375                         }
 376                 }
 377
 378
 379                 protected virtual void OnItemCommand (RepeaterCommandEventArgs e)
 380                 {
 381                         RepeaterCommandEventHandler h = (RepeaterCommandEventHandler) Events [ItemCommandEvent];
 382                         if (h != null)
 383                                 h (this, e);
 384                 }
 385
 386                 static readonly object ItemCommandEvent = new object ();
 387
 388                 [WebSysDescription ("")]
 389                 [WebCategory ("Action")]
 390                 public event RepeaterCommandEventHandler ItemCommand {
 391                         add { Events.AddHandler (ItemCommandEvent, value); }
 392                         remove { Events.RemoveHandler (ItemCommandEvent, value); }
 393                 }
 394
 395
 396                 protected virtual void OnItemCreated (RepeaterItemEventArgs e)
 397                 {
 398                         RepeaterItemEventHandler h = (RepeaterItemEventHandler) Events [ItemCreatedEvent];
 399                         if (h != null)
 400                                 h (this, e);
 401                 }
 402
 403                 static readonly object ItemCreatedEvent = new object ();
 404
 405                 [WebSysDescription ("")]
 406                 [WebCategory ("Behavior")]
 407                 public event RepeaterItemEventHandler ItemCreated {
 408                         add { Events.AddHandler (ItemCreatedEvent, value); }
 409                         remove { Events.RemoveHandler (ItemCreatedEvent, value); }
 410                 }
 411
 412                 protected virtual void OnItemDataBound (RepeaterItemEventArgs e)
 413                 {
 414                         RepeaterItemEventHandler h = (RepeaterItemEventHandler) Events [ItemDataBoundEvent];
 415                         if (h != null)
 416                                 h (this, e);
 417                 }
 418
 419                 static readonly object ItemDataBoundEvent = new object ();
 420
 421                 [WebSysDescription ("")]
 422                 [WebCategory ("Behavior")]
 423                 public event RepeaterItemEventHandler ItemDataBound {
 424                         add { Events.AddHandler (ItemDataBoundEvent, value); }
 425                         remove { Events.RemoveHandler (ItemDataBoundEvent, value); }
 426                 }
 427
 428                 protected bool Initialized {
 429                         get { return initialized; }
 430                 }
 431
 432                 protected bool IsBoundUsingDataSourceID
 433                 {
 434                         get { return (DataSourceID.Length != 0); }
 435                 }
 436
 437                 protected bool RequiresDataBinding
 438                 {
 439                         get { return requiresDataBinding; }
 440                         set {
 441                                 requiresDataBinding = value;
 442                                 if (value && preRendered && IsBoundUsingDataSourceID && Page != null && !Page.IsCallback)
 443                                         EnsureDataBound ();
 444                         }
 445                 }
 446
 447                 protected DataSourceSelectArguments SelectArguments
 448                 {
 449                         get {
 450                                 // MSDN: The first call to the SelectArguments property calls the
 451                                 // CreateDataSourceSelectArguments method to return the Empty value.
 452                                 if (selectArguments == null)
 453                                         selectArguments = CreateDataSourceSelectArguments();
 454                                 return selectArguments;
 455                         }
 456                 }
 457
 458                 protected virtual DataSourceSelectArguments CreateDataSourceSelectArguments ()
 459                 {
 460                         // MSDN: Returns the Empty value.
 461                         return DataSourceSelectArguments.Empty;
 462                 }
 463
 464                 protected void EnsureDataBound ()
 465                 {
 466                         if (IsBoundUsingDataSourceID && RequiresDataBinding)
 467                                 DataBind ();
 468                 }
 469
 470                 void SelectCallback (IEnumerable data)
 471                 {
 472                         this.data = data;
 473                 }
 474
 475                 protected virtual
 476                 IEnumerable GetData ()
 477                 {
 478                         IEnumerable result;
 479                         if (IsBoundUsingDataSourceID) {
 480                                 if (DataSourceID.Length == 0)
 481                                         return null;
 482
 483                                 if (boundDataSource == null)
 484                                         return null;
 485
 486                                 DataSourceView dsv = boundDataSource.GetView (String.Empty);
 487                                 dsv.Select (SelectArguments, new DataSourceViewSelectCallback (SelectCallback));
 488
 489                                 result = data;
 490                                 data = null;
 491                         }
 492                         else
 493                                 result = DataSourceResolver.ResolveDataSource (DataSource, DataMember);
 494
 495                         return result;
 496                 }
 497
 498                 protected virtual void OnDataPropertyChanged ()
 499                 {
 500                         if (Initialized)
 501                                 RequiresDataBinding = true;
 502                 }
 503
 504                 protected virtual void OnDataSourceViewChanged (object sender, EventArgs e)
 505                 {
 506                         RequiresDataBinding = true;
 507                 }
 508
 509                 protected internal override void OnInit (EventArgs e)
 510                 {
 511                         base.OnInit (e);
 512                         Page page = Page;
 513                         if (page != null) {
 514                                 page.PreLoad += new EventHandler (OnPagePreLoad);
 515
 516                                 if (!IsViewStateEnabled && page.IsPostBack)
 517                                         RequiresDataBinding = true;
 518                         }
 519                 }
 520
 521                 void OnPagePreLoad (object sender, EventArgs e)
 522                 {
 523                         Initialize ();
 524                 }
 525
 526                 protected internal override void OnLoad (EventArgs e)
 527                 {
 528                         if (!Initialized)
 529                                 Initialize ();
 530
 531                         base.OnLoad (e);
 532                 }
 533
 534                 void Initialize ()
 535                 {
 536                         Page page = Page;
 537                         if (page != null) {
 538                                 if (!page.IsPostBack || (IsViewStateEnabled && (ViewState ["Items"] == null)))
 539                                         RequiresDataBinding = true;
 540                         }
 541
 542                         if (IsBoundUsingDataSourceID)
 543                                 ConnectToDataSource ();
 544
 545                         initialized = true;
 546                 }
 547
 548                 protected internal override void OnPreRender (EventArgs e)
 549                 {
 550                         preRendered = true;
 551                         EnsureDataBound ();
 552                         base.OnPreRender (e);
 553                 }
 554
 555                 void ConnectToDataSource ()
 556                 {
 557                         /* verify that the data source exists and is an IDataSource */
 558                         object ctrl = null;
 559                         if (Parent != null)
 560                                 ctrl = Parent.FindControl (DataSourceID);
 561
 562                         if (ctrl == null || !(ctrl is IDataSource)) {
 563                                 string format;
 564
 565                                 if (ctrl == null)
 566                                         format = "DataSourceID of '{0}' must be the ID of a control of type IDataSource.  A control with ID '{1}' could not be found.";
 567                                 else
 568                                         format = "DataSourceID of '{0}' must be the ID of a control of type IDataSource.  '{1}' is not an IDataSource.";
 569
 570                                 throw new HttpException (String.Format (format, ID, DataSourceID));
 571                         }
 572
 573                         boundDataSource = (IDataSource)ctrl;
 574                         boundDataSource.GetView (String.Empty).DataSourceViewChanged += new EventHandler(OnDataSourceViewChanged);
 575                 }
 576         }
 577 }