mcs/class/System.Web.Mobile/System.Web.UI.MobileControls/PagedControl.cs

   1
   2 //
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   4 // a copy of this software and associated documentation files (the
   5 // "Software"), to deal in the Software without restriction, including
   6 // without limitation the rights to use, copy, modify, merge, publish,
   7 // distribute, sublicense, and/or sell copies of the Software, and to
   8 // permit persons to whom the Software is furnished to do so, subject to
   9 // the following conditions:
  10 //
  11 // The above copyright notice and this permission notice shall be
  12 // included in all copies or substantial portions of the Software.
  13 //
  14 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  15 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  16 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  17 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  18 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  19 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  20 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  21 //
  22 /**
  23  * Project   : Mono
  24  * Namespace : System.Web.UI.MobileControls
  25  * Class     : PagedControl
  26  * Author    : Gaurav Vaish
  27  *
  28  * Copyright : 2003 with Gaurav Vaish, and with
  29  *             Ximian Inc
  30  */
  31
  32 using System.Web.UI;
  33 using System.Web.Mobile;
  34
  35 namespace System.Web.UI.MobileControls
  36 {
  37         public abstract class PagedControl : MobileControl
  38         {
  39                 private static readonly object LoadItemsEvent    = new object();
  40
  41                 private int itemCount = 0;
  42                 private ItemPager itemPager;
  43                 private bool pagingCharsChanged = false;
  44
  45                 protected PagedControl()
  46                 {
  47                 }
  48
  49                 public event LoadItemsEventHandler LoadItems
  50                 {
  51                         add
  52                         {
  53                                 Events.AddHandler(LoadItemsEvent, value);
  54                         }
  55                         remove
  56                         {
  57                                 Events.RemoveHandler(LoadItemsEvent, value);
  58                         }
  59                 }
  60
  61                 private int PagerItemIndex
  62                 {
  63                         get
  64                         {
  65                                 return (itemPager == null ? 0 : itemPager.ItemIndex);
  66                         }
  67                 }
  68
  69                 private int PagerItemCount
  70                 {
  71                         get
  72                         {
  73                                 return (itemPager == null ? InternalItemCount :
  74                                             itemPager.ItemCount);
  75                         }
  76                 }
  77
  78                 protected abstract int InternalItemCount { get; }
  79
  80                 public int FirstVisibleItemIndex
  81                 {
  82                         get
  83                         {
  84                                 if(!IsCustomPaging && EnablePagination)
  85                                         return PagerItemIndex;
  86                                 return 0;
  87                         }
  88                 }
  89
  90                 private bool IsCustomPaging
  91                 {
  92                         get
  93                         {
  94                                 return (itemCount > 0);
  95                         }
  96                 }
  97
  98                 public int ItemCount
  99                 {
 100                         get
 101                         {
 102                                 return itemCount;
 103                         }
 104                         set
 105                         {
 106                                 itemCount = value;
 107                         }
 108                 }
 109
 110                 public int ItemWeight
 111                 {
 112                         get
 113                         {
 114                                 return ControlPager.DefaultWeight;
 115                         }
 116                 }
 117
 118                 public int ItemsPerPage
 119                 {
 120                         get
 121                         {
 122                                 object o = ViewState["ItemsPerPage"];
 123                                 if(o != null)
 124                                         return (int)o;
 125                                 return 0;
 126                         }
 127                         set
 128                         {
 129                                 ViewState["ItemsPerPage"] = value;
 130                         }
 131                 }
 132
 133                 public int VisibleItemCount
 134                 {
 135                         get
 136                         {
 137                                 if(IsCustomPaging || !EnablePagination)
 138                                         return InternalItemCount;
 139                                 return PagerItemCount;
 140                         }
 141                 }
 142
 143                 public override int VisibleWeight
 144                 {
 145                         get
 146                         {
 147                                 if(VisibleItemCount == -1)
 148                                         return 0;
 149                                 return VisibleItemCount * GetItemWeight();
 150                         }
 151                 }
 152
 153                 private int GetItemWeight()
 154                 {
 155                         int iw = Adapter.ItemWeight;
 156                         if(iw == ControlPager.UseDefaultWeight)
 157                                 return ItemWeight;
 158                         return iw;
 159                 }
 160
 161                 protected virtual void OnLoadItems(LoadItemsEventArgs e)
 162                 {
 163                         LoadItemsEventHandler lieh = (LoadItemsEventHandler)(Events[LoadItemsEvent]);
 164                         if(lieh != null)
 165                                 lieh(this, e);
 166                 }
 167
 168                 private void OnLoadItems()
 169                 {
 170                         OnLoadItems(new LoadItemsEventArgs(PagerItemIndex, PagerItemCount));
 171                 }
 172
 173                 protected override void OnPageChange(int oldPageIndex, int newPageIndex)
 174                 {
 175                         pagingCharsChanged = true;
 176                 }
 177
 178                 protected override void OnPreRender(EventArgs e)
 179                 {
 180                         if(IsCustomPaging)
 181                         {
 182                                 if(!Page.IsPostBack || Form.PaginationStateChanged
 183                                    || pagingCharsChanged || !IsViewStateEnabled())
 184                                 {
 185                                         OnLoadItems();
 186                                 }
 187                         }
 188                         base.OnPreRender(e);
 189                 }
 190
 191                 private bool IsViewStateEnabled()
 192                 {
 193                         Control ctrl = this;
 194                         while(ctrl != null && ctrl.EnableViewState)
 195                         {
 196                                 ctrl = ctrl.Parent;
 197                         }
 198                         return (ctrl == null);
 199                 }
 200
 201                 public override void PaginateRecursive(ControlPager pager)
 202                 {
 203                         int ic = 0;
 204                         int ipp = 0;
 205                         if(IsCustomPaging || InternalItemCount == 0)
 206                                 ic = ItemCount;
 207                         ipp = ItemsPerPage;
 208                         itemPager = pager.GetItemPager(this, ic, ipp, GetItemWeight());
 209                 }
 210         }
 211 }