mcs/class/referencesource/System.Web/UI/WebParts/CatalogZoneBase.cs

   1 //------------------------------------------------------------------------------
   2 // <copyright file="CatalogZoneBase.cs" company="Microsoft">
   3 //     Copyright (c) Microsoft Corporation.  All rights reserved.
   4 // </copyright>
   5 //------------------------------------------------------------------------------
   6
   7 namespace System.Web.UI.WebControls.WebParts {
   8
   9     using System;
  10     using System.Collections;
  11     using System.Collections.Specialized;
  12     using System.ComponentModel;
  13     using System.Drawing;
  14     using System.Globalization;
  15     using System.Web;
  16     using System.Web.UI;
  17     using System.Web.UI.WebControls;
  18     using System.Web.Util;
  19
  20     public abstract class CatalogZoneBase : ToolZone, IPostBackDataHandler {
  21
  22         private CatalogPartCollection _catalogParts;
  23
  24         private string[] _selectedCheckBoxValues;
  25         private string _selectedZoneID;
  26         private string _selectedCatalogPartID;
  27
  28         private const int baseIndex = 0;
  29         private const int addVerbIndex = 1;
  30         private const int closeVerbIndex = 2;
  31         private const int partLinkStyleIndex = 3;
  32         private const int selectedPartLinkStyleIndex = 4;
  33         private const int viewStateArrayLength = 5;
  34
  35         // Use same baseIndex as above
  36         private const int selectedCatalogPartIDIndex = 1;
  37         private const int controlStateArrayLength = 2;
  38
  39         private WebPartVerb _addVerb;
  40         private WebPartVerb _closeVerb;
  41         private Style _partLinkStyle;
  42         private Style _selectedPartLinkStyle;
  43         private CatalogPartChrome _catalogPartChrome;
  44
  45         private const string addEventArgument = "add";
  46         private const string closeEventArgument = "close";
  47         private const string selectEventArgument = "select";
  48
  49         protected CatalogZoneBase() : base(WebPartManager.CatalogDisplayMode) {
  50         }
  51
  52         [
  53         DefaultValue(null),
  54         DesignerSerializationVisibility(DesignerSerializationVisibility.Content),
  55         NotifyParentProperty(true),
  56         PersistenceMode(PersistenceMode.InnerProperty),
  57         WebCategory("Verbs"),
  58         WebSysDescription(SR.CatalogZoneBase_AddVerb),
  59         ]
  60         public virtual WebPartVerb AddVerb {
  61             get {
  62                 if (_addVerb == null) {
  63                     _addVerb = new WebPartCatalogAddVerb();
  64                     _addVerb.EventArgument = addEventArgument;
  65                     if (IsTrackingViewState) {
  66                         ((IStateManager)_addVerb).TrackViewState();
  67                     }
  68                 }
  69
  70                 return _addVerb;
  71             }
  72         }
  73
  74         internal string CheckBoxName {
  75             get {
  76                 return UniqueID + ID_SEPARATOR + "_checkbox";
  77             }
  78         }
  79
  80         [
  81         Browsable(false),
  82         DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
  83         ]
  84         public CatalogPartChrome CatalogPartChrome {
  85             get {
  86                 if (_catalogPartChrome == null) {
  87                     _catalogPartChrome = CreateCatalogPartChrome();
  88                 }
  89                 return _catalogPartChrome;
  90             }
  91         }
  92
  93         [
  94         Browsable(false),
  95         DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)
  96         ]
  97         public CatalogPartCollection CatalogParts {
  98             get {
  99                 if (_catalogParts == null) {
 100                     CatalogPartCollection catalogParts = CreateCatalogParts();
 101
 102                     // Verify that each CatalogPart has a nonempty ID.  Don't throw an exception in the designer,
 103                     // since we want only the offending control to render as an error block, not the whole CatalogZone.
 104                     if (!DesignMode) {
 105                         foreach (CatalogPart catalogPart in catalogParts) {
 106                             if (String.IsNullOrEmpty(catalogPart.ID)) {
 107                                 throw new InvalidOperationException(SR.GetString(SR.CatalogZoneBase_NoCatalogPartID));
 108                             }
 109                         }
 110                     }
 111
 112                     _catalogParts = catalogParts;
 113
 114                     // Call EnsureChildControls to parent the CatalogParts and set the WebPartManager, and Zone
 115                     EnsureChildControls();
 116                 }
 117
 118                 return _catalogParts;
 119             }
 120         }
 121
 122         [
 123         DefaultValue(null),
 124         DesignerSerializationVisibility(DesignerSerializationVisibility.Content),
 125         NotifyParentProperty(true),
 126         PersistenceMode(PersistenceMode.InnerProperty),
 127         WebCategory("Verbs"),
 128         WebSysDescription(SR.CatalogZoneBase_CloseVerb),
 129         ]
 130         public virtual WebPartVerb CloseVerb {
 131             get {
 132                 if (_closeVerb == null) {
 133                     _closeVerb = new WebPartCatalogCloseVerb();
 134                     _closeVerb.EventArgument = closeEventArgument;
 135                     if (IsTrackingViewState) {
 136                         ((IStateManager)_closeVerb).TrackViewState();
 137                     }
 138                 }
 139
 140                 return _closeVerb;
 141             }
 142         }
 143
 144         [
 145         WebSysDefaultValue(SR.CatalogZoneBase_DefaultEmptyZoneText)
 146         ]
 147         public override string EmptyZoneText {
 148             // Must look at viewstate directly instead of the property in the base class,
 149             // so we can distinguish between an unset property and a property set to String.Empty.
 150             get {
 151                 string s = (string)ViewState["EmptyZoneText"];
 152                 return((s == null) ? SR.GetString(SR.CatalogZoneBase_DefaultEmptyZoneText) : s);
 153             }
 154             set {
 155                 ViewState["EmptyZoneText"] = value;
 156             }
 157         }
 158
 159         [
 160         WebSysDefaultValue(SR.CatalogZoneBase_HeaderText),
 161         ]
 162         public override string HeaderText {
 163             get {
 164                 string s = (string)ViewState["HeaderText"];
 165                 return((s == null) ? SR.GetString(SR.CatalogZoneBase_HeaderText) : s);
 166             }
 167             set {
 168                 ViewState["HeaderText"] = value;
 169             }
 170         }
 171
 172         [
 173         WebSysDefaultValue(SR.CatalogZoneBase_InstructionText),
 174         ]
 175         public override string InstructionText {
 176             get {
 177                 string s = (string)ViewState["InstructionText"];
 178                 return((s == null) ? SR.GetString(SR.CatalogZoneBase_InstructionText) : s);
 179             }
 180             set {
 181                 ViewState["InstructionText"] = value;
 182             }
 183         }
 184
 185         [
 186         DefaultValue(null),
 187         NotifyParentProperty(true),
 188         DesignerSerializationVisibility(DesignerSerializationVisibility.Content),
 189         PersistenceMode(PersistenceMode.InnerProperty),
 190         WebCategory("Styles"),
 191         WebSysDescription(SR.CatalogZoneBase_PartLinkStyle),
 192         ]
 193         public Style PartLinkStyle {
 194             get {
 195                 if (_partLinkStyle == null) {
 196                     _partLinkStyle = new Style();
 197                     if (IsTrackingViewState) {
 198                         ((IStateManager)_partLinkStyle).TrackViewState();
 199                     }
 200                 }
 201
 202                 return _partLinkStyle;
 203             }
 204         }
 205
 206         [
 207         DefaultValue(""),
 208         Themeable(false),
 209         WebCategory("Behavior"),
 210         WebSysDescription(SR.CatalogZoneBase_SelectedCatalogPartID),
 211         ]
 212         public string SelectedCatalogPartID {
 213             get {
 214                 if (String.IsNullOrEmpty(_selectedCatalogPartID)) {
 215                     if (DesignMode) {
 216                         return String.Empty;
 217                     }
 218                     else {
 219                         CatalogPartCollection catalogParts = CatalogParts;
 220                         if (catalogParts != null && catalogParts.Count > 0) {
 221                             return catalogParts[0].ID;
 222                         } else {
 223                             return String.Empty;
 224                         }
 225                     }
 226                 }
 227                 else {
 228                     return _selectedCatalogPartID;
 229                 }
 230             }
 231             set {
 232                 _selectedCatalogPartID = value;
 233             }
 234         }
 235
 236         //
 237         private CatalogPart SelectedCatalogPart {
 238             get {
 239                 CatalogPartCollection catalogParts = CatalogParts;
 240                 if (catalogParts != null && catalogParts.Count > 0) {
 241                     if (String.IsNullOrEmpty(_selectedCatalogPartID)) {
 242                         return catalogParts[0];
 243                     }
 244                     else {
 245                         return catalogParts[_selectedCatalogPartID];
 246                     }
 247                 }
 248                 else {
 249                     // If there are no catalog parts, return null
 250                     return null;
 251                 }
 252             }
 253         }
 254
 255         [
 256         Localizable(true),
 257         WebSysDefaultValue(SR.CatalogZoneBase_DefaultSelectTargetZoneText),
 258         WebCategory("Behavior"),
 259         WebSysDescription(SR.CatalogZoneBase_SelectTargetZoneText),
 260         ]
 261         public virtual string SelectTargetZoneText {
 262             get {
 263                 string s = (string)ViewState["SelectTargetZoneText"];
 264                 return((s == null) ? SR.GetString(SR.CatalogZoneBase_DefaultSelectTargetZoneText) : s);
 265             }
 266             set {
 267                 ViewState["SelectTargetZoneText"] = value;
 268             }
 269         }
 270
 271         [
 272         DefaultValue(null),
 273         NotifyParentProperty(true),
 274         DesignerSerializationVisibility(DesignerSerializationVisibility.Content),
 275         PersistenceMode(PersistenceMode.InnerProperty),
 276         WebCategory("Styles"),
 277         WebSysDescription(SR.CatalogZoneBase_SelectedPartLinkStyle),
 278         ]
 279         public Style SelectedPartLinkStyle {
 280             get {
 281                 if (_selectedPartLinkStyle == null) {
 282                     _selectedPartLinkStyle = new Style();
 283                     if (IsTrackingViewState) {
 284                         ((IStateManager)_selectedPartLinkStyle).TrackViewState();
 285                     }
 286                 }
 287
 288                 return _selectedPartLinkStyle;
 289             }
 290         }
 291
 292         [
 293         DefaultValue(true),
 294         WebCategory("Behavior"),
 295         WebSysDescription(SR.CatalogZoneBase_ShowCatalogIcons),
 296         ]
 297         public virtual bool ShowCatalogIcons {
 298             get {
 299                 object b = ViewState["ShowCatalogIcons"];
 300                 return (b != null) ? (bool)b : true;
 301             }
 302             set {
 303                 ViewState["ShowCatalogIcons"] = value;
 304             }
 305         }
 306
 307         private string ZonesID {
 308             get {
 309                 return UniqueID + ID_SEPARATOR + "_zones";
 310             }
 311         }
 312
 313         private void AddSelectedWebParts() {
 314             WebPartZoneBase selectedZone = null;
 315             if (WebPartManager != null) {
 316                 selectedZone = WebPartManager.Zones[_selectedZoneID];
 317             }
 318
 319             CatalogPart selectedCatalogPart = SelectedCatalogPart;
 320             WebPartDescriptionCollection availableWebParts = null;
 321             if (selectedCatalogPart != null) {
 322                 availableWebParts = selectedCatalogPart.GetAvailableWebPartDescriptions();
 323             }
 324
 325             if (selectedZone != null && selectedZone.AllowLayoutChange &&
 326                 _selectedCheckBoxValues != null && availableWebParts != null) {
 327                 ArrayList selectedWebParts = new ArrayList();
 328
 329                 // Fetch all of the WebParts before calling AddWebPart() on any of them.
 330                 // This is necessary if the CatalogPart would refresh its list of
 331                 // AvailableWebPartDescriptions in response to adding a WebPart.
 332                 // PageCatalogPart is an example of this. (VSWhidbey 337539)
 333                 for (int i = 0; i < _selectedCheckBoxValues.Length; i++) {
 334                     string value = _selectedCheckBoxValues[i];
 335                     WebPartDescription webPartDescription = availableWebParts[value];
 336                     if (webPartDescription != null) {
 337                         WebPart part = selectedCatalogPart.GetWebPart(webPartDescription);
 338                         if (part != null) {
 339                             selectedWebParts.Add(part);
 340                         }
 341                     }
 342                 }
 343
 344                 AddWebParts(selectedWebParts, selectedZone);
 345             }
 346         }
 347
 348         private void AddWebParts(ArrayList webParts, WebPartZoneBase zone) {
 349             // Add web parts from the list in reverse order, so they appear in the zone in the same
 350             // order they were returned from the catalog part. (VSWhidbey 77750)
 351             webParts.Reverse();
 352
 353             foreach (WebPart part in webParts) {
 354                 WebPartZoneBase targetZone = zone;
 355                 if (part.AllowZoneChange == false && part.Zone != null) {
 356                     targetZone = part.Zone;
 357                 }
 358
 359                 // WebPartManager is checked for null in AddWebParts()
 360                 Debug.Assert(WebPartManager != null);
 361                 // Add new parts to the top of the Zone, so the user will see them without scrolling the page
 362                 WebPartManager.AddWebPart(part, targetZone, 0);
 363             }
 364         }
 365
 366         protected override void Close() {
 367             if (WebPartManager != null) {
 368                 WebPartManager.DisplayMode = WebPartManager.BrowseDisplayMode;
 369             }
 370         }
 371
 372         protected virtual CatalogPartChrome CreateCatalogPartChrome() {
 373             return new CatalogPartChrome(this);
 374         }
 375
 376         protected abstract CatalogPartCollection CreateCatalogParts();
 377
 378         /// <internalonly/>
 379         protected internal override void CreateChildControls() {
 380             Controls.Clear();
 381
 382             //
 383             foreach (CatalogPart catalogPart in CatalogParts) {
 384                 catalogPart.SetWebPartManager(WebPartManager);
 385                 catalogPart.SetZone(this);
 386                 Controls.Add(catalogPart);
 387             }
 388         }
 389
 390         internal string GetCheckBoxID(string value) {
 391             return ClientID + ClientIDSeparator + "_checkbox" + ClientIDSeparator + value;
 392         }
 393
 394         // Called by a derived class if the list of CatalogParts changes, and they want CreateCatalogParts()
 395         // to be called again.
 396         protected void InvalidateCatalogParts() {
 397             _catalogParts = null;
 398             ChildControlsCreated = false;
 399         }
 400
 401         /// <devdoc>
 402         /// Loads the control state for those properties that should persist across postbacks
 403         /// even when EnableViewState=false.
 404         /// </devdoc>
 405         protected internal override void LoadControlState(object savedState) {
 406             if (savedState == null) {
 407                 base.LoadControlState(null);
 408             }
 409             else {
 410                 object[] myState = (object[])savedState;
 411                 if (myState.Length != controlStateArrayLength) {
 412                     throw new ArgumentException(SR.GetString(SR.Invalid_ControlState));
 413                 }
 414
 415                 base.LoadControlState(myState[baseIndex]);
 416                 if (myState[selectedCatalogPartIDIndex] != null) {
 417                     _selectedCatalogPartID = (string)myState[selectedCatalogPartIDIndex];
 418                 }
 419             }
 420         }
 421
 422         protected virtual bool LoadPostData(string postDataKey, NameValueCollection postCollection) {
 423
 424             string selectedCheckBoxValues = postCollection[CheckBoxName];
 425             if (!String.IsNullOrEmpty(selectedCheckBoxValues)) {
 426
 427                 //Validate postback reference if exists in the postdata.
 428                 ValidateEvent(CheckBoxName);
 429
 430                 _selectedCheckBoxValues = selectedCheckBoxValues.Split(',');
 431             }
 432
 433             _selectedZoneID = postCollection[ZonesID];
 434
 435             // Do not raise a changed event
 436             return false;
 437         }
 438
 439         protected override void LoadViewState(object savedState) {
 440             if (savedState == null) {
 441                 base.LoadViewState(null);
 442             }
 443             else {
 444                 object[] myState = (object[]) savedState;
 445                 if (myState.Length != viewStateArrayLength) {
 446                     throw new ArgumentException(SR.GetString(SR.ViewState_InvalidViewState));
 447                 }
 448
 449                 base.LoadViewState(myState[baseIndex]);
 450                 if (myState[addVerbIndex] != null) {
 451                     ((IStateManager) AddVerb).LoadViewState(myState[addVerbIndex]);
 452                 }
 453                 if (myState[closeVerbIndex] != null) {
 454                     ((IStateManager) CloseVerb).LoadViewState(myState[closeVerbIndex]);
 455                 }
 456                 if (myState[partLinkStyleIndex] != null) {
 457                     ((IStateManager) PartLinkStyle).LoadViewState(myState[partLinkStyleIndex]);
 458                 }
 459                 if (myState[selectedPartLinkStyleIndex] != null) {
 460                     ((IStateManager) SelectedPartLinkStyle).LoadViewState(myState[selectedPartLinkStyleIndex]);
 461                 }
 462             }
 463         }
 464
 465         protected internal override void OnInit(EventArgs e) {
 466             base.OnInit(e);
 467
 468             Page page = Page;
 469             Debug.Assert(page != null);
 470             if (page != null) {
 471                 page.RegisterRequiresControlState(this);
 472             }
 473         }
 474
 475         // We don't need to handle WebPartManager.DisplayModeChanged in this class.
 476         // We need it in EditorZoneBase since the available editor parts changes when the
 477         // WebPartToEdit changes, but the list of catalog parts never changes
 478         // when the DisplayMode changes.
 479
 480         protected internal override void OnPreRender(EventArgs e) {
 481             base.OnPreRender(e);
 482             CatalogPartChrome.PerformPreRender();
 483             Page.RegisterRequiresPostBack(this);
 484         }
 485
 486         protected override void RaisePostBackEvent(string eventArgument) {
 487             string[] eventArguments = eventArgument.Split(ID_SEPARATOR);
 488
 489             if ((eventArguments.Length == 2) && (eventArguments[0] == selectEventArgument)) {
 490                 SelectedCatalogPartID = eventArguments[1];
 491             }
 492             else if (String.Equals(eventArgument, addEventArgument, StringComparison.OrdinalIgnoreCase)) {
 493                 if (AddVerb.Visible && AddVerb.Enabled) {
 494                     AddSelectedWebParts();
 495                 }
 496             }
 497             else if (String.Equals(eventArgument, closeEventArgument, StringComparison.OrdinalIgnoreCase)) {
 498                 if (CloseVerb.Visible && CloseVerb.Enabled) {
 499                     Close();
 500                 }
 501             }
 502             else {
 503                 base.RaisePostBackEvent(eventArgument);
 504             }
 505         }
 506
 507         protected internal override void Render(HtmlTextWriter writer) {
 508             if (Page != null) {
 509                 Page.VerifyRenderingInServerForm(this);
 510             }
 511
 512             base.Render(writer);
 513         }
 514
 515         protected override void RenderBody(HtmlTextWriter writer) {
 516             RenderBodyTableBeginTag(writer);
 517             if (DesignMode) {
 518                 RenderDesignerRegionBeginTag(writer, Orientation.Vertical);
 519             }
 520
 521             CatalogPartCollection catalogParts = CatalogParts;
 522             if (catalogParts != null && catalogParts.Count > 0) {
 523                 bool firstCell = true;
 524                 // Only render links if there is more than 1 catalog part (VSWhidbey 77672)
 525                 if (catalogParts.Count > 1) {
 526                     writer.RenderBeginTag(HtmlTextWriterTag.Tr);
 527                     writer.RenderBeginTag(HtmlTextWriterTag.Td);
 528                     firstCell = false;
 529                     RenderCatalogPartLinks(writer);
 530                     writer.RenderEndTag();  // Td
 531                     writer.RenderEndTag();  // Tr
 532                 }
 533
 534                 CatalogPartChrome chrome = CatalogPartChrome;
 535                 if (DesignMode) {
 536                     foreach (CatalogPart catalogPart in catalogParts) {
 537                         RenderCatalogPart(writer, catalogPart, chrome, ref firstCell);
 538                     }
 539                 }
 540                 else {
 541                     CatalogPart selectedCatalogPart = SelectedCatalogPart;
 542                     if (selectedCatalogPart != null) {
 543                         RenderCatalogPart(writer, selectedCatalogPart, chrome, ref firstCell);
 544                     }
 545                 }
 546
 547                 writer.RenderBeginTag(HtmlTextWriterTag.Tr);
 548
 549                 // Mozilla renders padding on an empty TD without this attribute
 550                 writer.AddStyleAttribute(HtmlTextWriterStyle.Padding, "0");
 551
 552                 // Add an extra row with height of 100%, to Microsoft up any extra space
 553                 // if the height of the zone is larger than its contents
 554                 // Mac IE needs height=100% set on <td> instead of <tr>
 555                 writer.AddStyleAttribute(HtmlTextWriterStyle.Height, "100%");
 556
 557                 writer.RenderBeginTag(HtmlTextWriterTag.Td);
 558                 writer.RenderEndTag(); // Td
 559                 writer.RenderEndTag(); // Tr
 560             }
 561             else {
 562                 RenderEmptyZoneText(writer);
 563             }
 564
 565             if (DesignMode) {
 566                 RenderDesignerRegionEndTag(writer);
 567             }
 568             RenderBodyTableEndTag(writer);
 569         }
 570
 571         private void RenderCatalogPart(HtmlTextWriter writer, CatalogPart catalogPart, CatalogPartChrome chrome, ref bool firstCell) {
 572             writer.RenderBeginTag(HtmlTextWriterTag.Tr);
 573
 574             if (!firstCell) {
 575                 writer.AddStyleAttribute(HtmlTextWriterStyle.PaddingTop, "0");
 576             }
 577             writer.RenderBeginTag(HtmlTextWriterTag.Td);
 578             firstCell = false;
 579
 580             chrome.RenderCatalogPart(writer, catalogPart);
 581
 582             writer.RenderEndTag();  // Td
 583             writer.RenderEndTag();  // Tr
 584         }
 585
 586         protected virtual void RenderCatalogPartLinks(HtmlTextWriter writer) {
 587             RenderInstructionText(writer);
 588
 589             CatalogPart selectedCatalogPart = SelectedCatalogPart;
 590             foreach (CatalogPart catalogPart in CatalogParts) {
 591                 WebPartDescriptionCollection availableWebParts = catalogPart.GetAvailableWebPartDescriptions();
 592                 int count = ((availableWebParts != null) ? availableWebParts.Count : 0);
 593
 594                 string displayTitle = catalogPart.DisplayTitle;
 595                 //
 596                 string text = displayTitle + " (" + count.ToString(CultureInfo.CurrentCulture) + ")";
 597
 598                 if (catalogPart == selectedCatalogPart) {
 599                     Label label = new Label();
 600                     label.Text = text;
 601                     label.Page = Page;
 602                     label.ApplyStyle(SelectedPartLinkStyle);
 603                     label.RenderControl(writer);
 604                 }
 605                 else {
 606                     Debug.Assert(!String.IsNullOrEmpty(catalogPart.ID));
 607                     string eventArgument = selectEventArgument + ID_SEPARATOR + catalogPart.ID;
 608
 609                     ZoneLinkButton linkButton = new ZoneLinkButton(this, eventArgument);
 610                     linkButton.Text = text;
 611                     linkButton.ToolTip = SR.GetString(SR.CatalogZoneBase_SelectCatalogPart, displayTitle);
 612                     linkButton.Page = Page;
 613                     linkButton.ApplyStyle(PartLinkStyle);
 614                     linkButton.RenderControl(writer);
 615                 }
 616
 617                 writer.WriteBreak();
 618             }
 619
 620             writer.WriteBreak();
 621         }
 622
 623         private void RenderEmptyZoneText(HtmlTextWriter writer) {
 624             string emptyZoneText = EmptyZoneText;
 625             if (!String.IsNullOrEmpty(emptyZoneText)) {
 626                 writer.RenderBeginTag(HtmlTextWriterTag.Tr);
 627
 628                 writer.AddAttribute(HtmlTextWriterAttribute.Valign, "top");
 629
 630                 Style emptyZoneTextStyle = EmptyZoneTextStyle;
 631                 if (!emptyZoneTextStyle.IsEmpty) {
 632                     emptyZoneTextStyle.AddAttributesToRender(writer, this);
 633                 }
 634                 writer.RenderBeginTag(HtmlTextWriterTag.Td);
 635
 636                 writer.Write(emptyZoneText);
 637
 638                 writer.RenderEndTag();  // Td
 639                 writer.RenderEndTag();  // Tr
 640             }
 641         }
 642
 643         protected override void RenderFooter(HtmlTextWriter writer) {
 644             writer.AddStyleAttribute(HtmlTextWriterStyle.Margin, "4px");
 645             writer.RenderBeginTag(HtmlTextWriterTag.Div);
 646
 647             DropDownList zonesDropDownList = new DropDownList();
 648             zonesDropDownList.ClientIDMode = ClientIDMode.AutoID;
 649             zonesDropDownList.ID = ZonesID;
 650
 651             // Populate the DropDownList
 652             if (DesignMode) {
 653                 // Add sample zone to dropdown
 654                 zonesDropDownList.Items.Add(SR.GetString(SR.Zone_SampleHeaderText));
 655             }
 656             else {
 657                 if (WebPartManager != null && WebPartManager.Zones != null) {
 658                     foreach (WebPartZoneBase zone in WebPartManager.Zones) {
 659                         if (zone.AllowLayoutChange) {
 660                             Debug.Assert(!String.IsNullOrEmpty(zone.ID));
 661                             ListItem item = new ListItem(zone.DisplayTitle, zone.ID);
 662                             if (String.Equals(zone.ID, _selectedZoneID, StringComparison.OrdinalIgnoreCase)) {
 663                                 item.Selected = true;
 664                             }
 665                             zonesDropDownList.Items.Add(item);
 666                         }
 667                     }
 668                 }
 669             }
 670
 671             LabelStyle.AddAttributesToRender(writer, this);
 672             // Only render the "for" attribute if we are going to render the associated DropDownList (VSWhidbey 541458)
 673             if (zonesDropDownList.Items.Count > 0) {
 674                 writer.AddAttribute(HtmlTextWriterAttribute.For, zonesDropDownList.ClientID);
 675             }
 676             writer.RenderBeginTag(HtmlTextWriterTag.Label);
 677             writer.Write(SelectTargetZoneText);
 678             writer.RenderEndTag();
 679
 680             // Render &nbsp; before the DropDownList (VSWhidbey 77709)
 681             writer.Write("&nbsp;");
 682
 683             zonesDropDownList.ApplyStyle(EditUIStyle);
 684             // Do not render empty DropDownList (VSWhidbey 534498)
 685             if (zonesDropDownList.Items.Count > 0) {
 686                 zonesDropDownList.RenderControl(writer);
 687             }
 688
 689             writer.Write("&nbsp;");
 690
 691             RenderVerbs(writer);
 692
 693             writer.RenderEndTag();  // Div
 694         }
 695
 696         private void RenderInstructionText(HtmlTextWriter writer) {
 697             string instructionText = InstructionText;
 698             if (!String.IsNullOrEmpty(instructionText)) {
 699                 Label label = new Label();
 700                 label.Text = instructionText;
 701                 label.Page = Page;
 702                 label.ApplyStyle(InstructionTextStyle);
 703                 label.RenderControl(writer);
 704                 writer.WriteBreak();
 705                 writer.WriteBreak();
 706             }
 707         }
 708
 709         protected override void RenderVerbs(HtmlTextWriter writer) {
 710             int count = 0;
 711             bool originalAddVerbEnabled = false;
 712
 713             CatalogPart selectedCatalogPart = SelectedCatalogPart;
 714             if (selectedCatalogPart != null) {
 715                 WebPartDescriptionCollection availableWebParts = selectedCatalogPart.GetAvailableWebPartDescriptions();
 716                 count = ((availableWebParts != null) ? availableWebParts.Count : 0);
 717             }
 718
 719             // If the current CatalogPart has no WebPartDescriptions, disable the AddVerb
 720             if (count == 0) {
 721                 originalAddVerbEnabled = AddVerb.Enabled;
 722                 AddVerb.Enabled = false;
 723             }
 724
 725             try {
 726                 RenderVerbsInternal(writer, new WebPartVerb[] {AddVerb, CloseVerb});
 727             }
 728             finally {
 729                 if (count == 0) {
 730                     AddVerb.Enabled = originalAddVerbEnabled;
 731                 }
 732             }
 733         }
 734
 735         /// <devdoc>
 736         /// Saves the control state for those properties that should persist across postbacks
 737         /// even when EnableViewState=false.
 738         /// </devdoc>
 739         protected internal override object SaveControlState() {
 740             object[] myState = new object[controlStateArrayLength];
 741
 742             myState[baseIndex] = base.SaveControlState();
 743             if (!String.IsNullOrEmpty(_selectedCatalogPartID)) {
 744                 myState[selectedCatalogPartIDIndex] = _selectedCatalogPartID;
 745             }
 746
 747             for (int i=0; i < controlStateArrayLength; i++) {
 748                 if (myState[i] != null) {
 749                     return myState;
 750                 }
 751             }
 752
 753             // More performant to return null than an array of null values
 754             return null;
 755         }
 756
 757         protected override object SaveViewState() {
 758             object[] myState = new object[viewStateArrayLength];
 759
 760             myState[baseIndex] = base.SaveViewState();
 761             myState[addVerbIndex] = (_addVerb != null) ? ((IStateManager)_addVerb).SaveViewState() : null;
 762             myState[closeVerbIndex] = (_closeVerb != null) ? ((IStateManager)_closeVerb).SaveViewState() : null;
 763             myState[partLinkStyleIndex] = (_partLinkStyle != null) ? ((IStateManager)_partLinkStyle).SaveViewState() : null;
 764             myState[selectedPartLinkStyleIndex] = (_selectedPartLinkStyle != null) ? ((IStateManager)_selectedPartLinkStyle).SaveViewState() : null;
 765
 766             for (int i=0; i < viewStateArrayLength; i++) {
 767                 if (myState[i] != null) {
 768                     return myState;
 769                 }
 770             }
 771
 772             // More performant to return null than an array of null values
 773             return null;
 774         }
 775
 776         protected override void TrackViewState() {
 777             base.TrackViewState();
 778
 779             if (_addVerb != null) {
 780                 ((IStateManager) _addVerb).TrackViewState();
 781             }
 782             if (_closeVerb != null) {
 783                 ((IStateManager) _closeVerb).TrackViewState();
 784             }
 785             if (_partLinkStyle != null) {
 786                 ((IStateManager) _partLinkStyle).TrackViewState();
 787             }
 788             if (_selectedPartLinkStyle != null) {
 789                 ((IStateManager) _selectedPartLinkStyle).TrackViewState();
 790             }
 791         }
 792
 793         #region Implementation of IPostBackDataHandler
 794         bool IPostBackDataHandler.LoadPostData(string postDataKey, NameValueCollection postCollection) {
 795             return LoadPostData(postDataKey, postCollection);
 796         }
 797
 798         void IPostBackDataHandler.RaisePostDataChangedEvent() {
 799         }
 800         #endregion
 801     }
 802 }
 803