mcs/class/System.Design/System.ComponentModel.Design/SelectionService.cs

   1 //
   2 // System.ComponentModel.Design.SelectionService
   3 //
   4 // Authors:
   5 //        Ivan N. Zlatev (contact i-nZ.net)
   6 //
   7 // (C) 2006-2007 Ivan N. Zlatev
   8
   9 //
  10 // Permission is hereby granted, free of charge, to any person obtaining
  11 // a copy of this software and associated documentation files (the
  12 // "Software"), to deal in the Software without restriction, including
  13 // without limitation the rights to use, copy, modify, merge, publish,
  14 // distribute, sublicense, and/or sell copies of the Software, and to
  15 // permit persons to whom the Software is furnished to do so, subject to
  16 // the following conditions:
  17 //
  18 // The above copyright notice and this permission notice shall be
  19 // included in all copies or substantial portions of the Software.
  20 //
  21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28 //
  29 using System;
  30 using System.Collections;
  31 using System.ComponentModel;
  32 using System.ComponentModel.Design;
  33 using System.Windows.Forms;
  34
  35 namespace System.ComponentModel.Design
  36 {
  37
  38         internal class SelectionService : ISelectionService
  39         {
  40
  41                 private IServiceProvider _serviceProvider;
  42                 private ArrayList _selection;
  43                 private IComponent _primarySelection;
  44
  45                 public SelectionService (IServiceProvider provider)
  46                 {
  47                         _serviceProvider = provider;
  48                         _selection = new ArrayList();
  49
  50                         IComponentChangeService changeService = provider.GetService (typeof (IComponentChangeService)) as IComponentChangeService;
  51                         if (changeService != null)
  52                                 changeService.ComponentRemoving += new ComponentEventHandler (OnComponentRemoving);
  53                 }
  54
  55                 private void OnComponentRemoving (object sender, ComponentEventArgs args)
  56                 {
  57                         if (this.GetComponentSelected (args.Component))
  58                                 this.SetSelectedComponents (new IComponent[] { args.Component }, SelectionTypes.Remove);
  59                 }
  60
  61                 public event EventHandler SelectionChanging;
  62                 public event EventHandler SelectionChanged;
  63
  64                 public ICollection GetSelectedComponents()
  65                 {
  66                         if (_selection != null)
  67                                 return _selection.ToArray ();
  68
  69                         return new object[0];
  70                 }
  71
  72                 protected virtual void OnSelectionChanging ()
  73                 {
  74                         if (SelectionChanging != null)
  75                                 SelectionChanging (this, EventArgs.Empty);
  76                 }
  77
  78                 protected virtual void OnSelectionChanged ()
  79                 {
  80                         if (SelectionChanged != null)
  81                                 SelectionChanged (this, EventArgs.Empty);
  82                 }
  83
  84                 public object PrimarySelection {
  85                         get { return _primarySelection; }
  86                 }
  87
  88                 public int SelectionCount {
  89                         get {
  90                                 if (_selection != null)
  91                                         return _selection.Count;
  92
  93                                 return 0;
  94                         }
  95                 }
  96
  97
  98                 private IComponent RootComponent {
  99                         get {
 100                                 if (_serviceProvider != null) {
 101                                         IDesignerHost designerHost = _serviceProvider.GetService (typeof (IDesignerHost)) as IDesignerHost;
 102                                         if (designerHost != null)
 103                                                 return designerHost.RootComponent;
 104                                 }
 105                                 return null;
 106                         }
 107                 }
 108
 109                 public bool GetComponentSelected (object component)
 110                 {
 111                         if (_selection != null)
 112                                 return _selection.Contains (component);
 113
 114                         return false;
 115                 }
 116
 117                 public void SetSelectedComponents (ICollection components)
 118                 {
 119                         SetSelectedComponents (components, SelectionTypes.Auto);
 120                 }
 121
 122                 // If the array is a null reference or does not contain any components,
 123                 // SetSelectedComponents selects the top-level component in the designer.
 124                 //
 125                 public void SetSelectedComponents (ICollection components, SelectionTypes selectionType)
 126                 {
 127                         bool primary, add, remove, replace, toggle, auto;
 128                         primary = add = remove = replace = toggle = auto = false;
 129
 130                         OnSelectionChanging ();
 131
 132                         if (_selection == null)
 133                                 throw new InvalidOperationException("_selection == null");
 134
 135                         if (components == null || components.Count == 0) {
 136                                 components = new ArrayList ();
 137                                 ((ArrayList) components).Add (this.RootComponent);
 138                                 selectionType = SelectionTypes.Replace;
 139                         }
 140
 141                         if (!Enum.IsDefined (typeof (SelectionTypes), selectionType)) {
 142                                 selectionType = SelectionTypes.Auto;
 143                         }
 144
 145                         auto = ((selectionType & SelectionTypes.Auto) == SelectionTypes.Auto);
 146
 147
 148                         if (auto) {
 149                                 if ((((Control.ModifierKeys & Keys.Control) == Keys.Control) || ((Control.ModifierKeys & Keys.Shift) == Keys.Shift))) {
 150                                         toggle = true;
 151                                 }
 152                                 else if (components.Count == 1) {
 153                                         object component = null;
 154                                         foreach (object c in components) {
 155                                                 component = c;
 156                                                 break;
 157                                         }
 158
 159                                         if (this.GetComponentSelected (component))
 160                                                 primary = true;
 161                                         else
 162                                                 replace = true;
 163                                 }
 164                                 else {
 165                                         replace = true;
 166                                 }
 167                         }
 168                         else {
 169                                 primary = ((selectionType & SelectionTypes.Primary) == SelectionTypes.Primary);
 170                                 add = ((selectionType & SelectionTypes.Add) == SelectionTypes.Add);
 171                                 remove = ((selectionType & SelectionTypes.Remove) == SelectionTypes.Remove);
 172                                 toggle = ((selectionType & SelectionTypes.Toggle) == SelectionTypes.Toggle);
 173                                 replace = ((selectionType & SelectionTypes.Replace) == SelectionTypes.Replace);
 174
 175                         }
 176
 177
 178                         if (replace) {
 179                                 _selection.Clear ();
 180                                 add = true;
 181                         }
 182
 183                         if (add) {
 184                                 foreach (object component in components) {
 185                                         if (component is IComponent && !_selection.Contains (component)) {
 186                                                 _selection.Add (component);
 187                                                 _primarySelection = (IComponent) component;
 188                                         }
 189                                 }
 190                         }
 191
 192                         if (remove) {
 193                                 bool rootRemoved = false;
 194                                 foreach (object component in components) {
 195                                         if (component is IComponent && _selection.Contains (component))
 196                                                 _selection.Remove (component);
 197                                         if (component == this.RootComponent)
 198                                                 rootRemoved = true;
 199                                 }
 200                                 if (_selection.Count == 0) {
 201                                         if (rootRemoved) {
 202                                                 _primarySelection = null;
 203                                         } else {
 204                                                 _primarySelection = this.RootComponent;
 205                                                 _selection.Add (this.RootComponent);
 206                                         }
 207                                 }
 208                         }
 209
 210                         if (toggle) {
 211                                 foreach (object component in components) {
 212                                         if (component is IComponent) {
 213                                                 if (_selection.Contains (component)) {
 214                                                         _selection.Remove (component);
 215                                                         if (component == _primarySelection)
 216                                                                 _primarySelection = this.RootComponent;
 217                                                 }
 218                                                 else {
 219                                                         _selection.Add (component);
 220                                                         _primarySelection = (IComponent) component;
 221                                                 }
 222                                         }
 223                                 }
 224                         }
 225
 226                         if (primary) {
 227                                 object primarySelection = null;
 228
 229                                 foreach (object component in components) {
 230                                         primarySelection = component;
 231                                         break;
 232                                 }
 233
 234                                 if (!this.GetComponentSelected (primarySelection))
 235                                         _selection.Add (primarySelection);
 236
 237                                 _primarySelection = (IComponent) primarySelection;
 238                         }
 239
 240                         OnSelectionChanged ();
 241                 }
 242         }
 243 }