Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Web.Mobile/UI/MobileControls/ObjectListCommandCollection.cs

@@ -0,0 +1,249 @@
+//------------------------------------------------------------------------------
+// <copyright file="ObjectListCommandCollection.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>                                                                
+//------------------------------------------------------------------------------
+
+using System;
+using System.Collections;
+using System.ComponentModel;
+using System.Diagnostics;
+using System.Globalization;
+using System.Web;
+using System.Web.UI;
+using System.Web.UI.WebControls;
+using System.Web.UI.HtmlControls;
+using System.Security.Permissions;
+
+namespace System.Web.UI.MobileControls
+{
+    /*
+     * Object List Command Collection class.
+     *
+     * Copyright (c) 2000 Microsoft Corporation
+     */
+
+    /// <include file='doc\ObjectListCommandCollection.uex' path='docs/doc[@for="ObjectListCommandCollection"]/*' />
+    [AspNetHostingPermission(SecurityAction.LinkDemand, Level=AspNetHostingPermissionLevel.Minimal)]
+    [AspNetHostingPermission(SecurityAction.InheritanceDemand, Level=AspNetHostingPermissionLevel.Minimal)]
+    [Obsolete("The System.Web.Mobile.dll assembly has been deprecated and should no longer be used. For information about how to develop ASP.NET mobile applications, see http://go.microsoft.com/fwlink/?LinkId=157231.")]
+    public class ObjectListCommandCollection : ArrayListCollectionBase, IStateManager
+    {
+        // ObjectListCommandCollection has a special form of viewstate management.
+        // In normal operation, if you add, remove or modify commands in the 
+        // collection, the results are saved as part of view state.
+        //
+        // However, when showing the commands for an item, the ObjectList control
+        // raises an event that allows the application to alter the commands
+        // specifically for the item. These changes are considered local to the
+        // item, and are not saved.
+        //
+        // To do this, the class uses a private state, declared in the MarkState
+        // enumeration below. The following sequence of events are used:
+        //
+        // 1) Class is created. MarkState is set to MarkState.NotMarked.
+        // 2) Class is initialized from persistent values.
+        // 3) Framework calls TrackViewState. MarkState is set to MarkState.MArked.
+        // 4) Properties can be changed. Changes are reflected in viewstate.
+        // 5) Just before raising the ShowItemCommands event, the ObjectList control
+        //    calls GlobalStateSet. PreSaveViewState is called to create a 
+        //    snapshot of viewstate, and MarkState is set to MarkState.PostMarked.
+        // 6) If any changes are made after this, they will be ignored for view state
+        //    purposes.
+        // 7) The framework calls SaveViewState. Instead of the current view state
+        //    (which would include the changes made in Step 6), the snapshot view state
+        //     from step 5 is returned.
+
+        private enum MarkState
+        {
+            NotMarked,
+            Marked,
+            PostMarked,
+        }
+
+        private MarkState _markState = MarkState.NotMarked;
+        private bool _dirty;
+        private String[] _savedState;
+
+        internal ObjectListCommandCollection()
+        {
+        }
+
+        /// <include file='doc\ObjectListCommandCollection.uex' path='docs/doc[@for="ObjectListCommandCollection.this"]/*' />
+        public ObjectListCommand this[int index]
+        {
+            get
+            {
+                return (ObjectListCommand)Items[index];
+            }
+        }
+
+        /// <include file='doc\ObjectListCommandCollection.uex' path='docs/doc[@for="ObjectListCommandCollection.Clear"]/*' />
+        public void Clear()
+        {
+            foreach (ObjectListCommand command in Items)
+            {
+                command.Owner = null;
+            }
+            Items.Clear();
+            SetDirty();
+        }
+
+        /// <include file='doc\ObjectListCommandCollection.uex' path='docs/doc[@for="ObjectListCommandCollection.Add"]/*' />
+        public void Add(ObjectListCommand command)
+        {
+            AddAt(-1, command);
+        }
+
+        /// <include file='doc\ObjectListCommandCollection.uex' path='docs/doc[@for="ObjectListCommandCollection.AddAt"]/*' />
+        public void AddAt(int index, ObjectListCommand command)
+        {
+            if (index == -1)
+            {
+                Items.Add(command);
+            }
+            else
+            {
+                Items.Insert(index, command);
+            }
+            command.Owner = this;
+            SetDirty();
+        }
+
+        /// <include file='doc\ObjectListCommandCollection.uex' path='docs/doc[@for="ObjectListCommandCollection.Remove"]/*' />
+        public void Remove(String s)
+        {
+            RemoveAt(IndexOf(s));
+        }    
+
+        /// <include file='doc\ObjectListCommandCollection.uex' path='docs/doc[@for="ObjectListCommandCollection.RemoveAt"]/*' />
+        public void RemoveAt(int index)
+        {
+            (this[index]).Owner = null;
+            Items.RemoveAt(index);
+            SetDirty();
+        }
+
+        /// <include file='doc\ObjectListCommandCollection.uex' path='docs/doc[@for="ObjectListCommandCollection.IndexOf"]/*' />
+        public int IndexOf(String s)
+        {
+            int index = 0;
+            foreach (ObjectListCommand command in Items)
+            {
+                if (String.Compare(command.Name, s, StringComparison.OrdinalIgnoreCase) == 0)
+                {
+                    return index;
+                }
+                index++;
+            }
+            return -1;
+        }
+
+        internal void GlobalStateSet()
+        {
+            // Base commands have been set. From here, commands will only be
+            // modified on a per-item, non-persistent basis.
+
+            PreSaveViewState();
+            _markState = MarkState.PostMarked;
+        }
+
+        internal void SetDirty()
+        {
+            if (_markState == MarkState.Marked)
+            {
+                _dirty = true;
+            }
+        }
+
+        /////////////////////////////////////////////////////////////////////////
+        //  STATE MANAGEMENT
+        /////////////////////////////////////////////////////////////////////////
+
+        private void PreSaveViewState()
+        {
+            if (_dirty)
+            {
+                ArrayList commands = Items;
+                _savedState = new String[commands.Count * 2];
+                int i = 0;
+                foreach (ObjectListCommand command in commands)
+                {
+                    _savedState[i] = command.Name;
+                    _savedState[i + 1] = command.Text;
+                    i += 2;
+                }
+            }
+            else
+            {
+                _savedState = null;
+            }
+        }
+
+        /// <internalonly/>
+        protected bool IsTrackingViewState
+        {
+            get
+            {
+                return _markState != MarkState.NotMarked;
+            }
+        }
+
+        /// <internalonly/>
+        protected void TrackViewState() 
+        {
+            _markState = MarkState.Marked;
+        }
+
+        /// <internalonly/>
+        protected void LoadViewState(Object state) 
+        {
+            if (state != null)
+            {
+                String[] commandStates = (String[])state;
+                int count = commandStates.Length;
+                Clear();
+                for (int i = 0; i < count; i += 2)
+                {
+                    Add(new ObjectListCommand(commandStates[i], commandStates[i + 1]));
+                }
+            }
+        }
+
+        /// <internalonly/>
+        protected Object SaveViewState() 
+        {
+            if (_markState == MarkState.Marked)
+            {
+                PreSaveViewState();
+            }
+            return _savedState;
+        }
+
+        #region Implementation of IStateManager
+        /// <internalonly/>
+        bool IStateManager.IsTrackingViewState {
+            get {
+                return IsTrackingViewState;
+            }
+        }
+
+        /// <internalonly/>
+        void IStateManager.LoadViewState(object state) {
+            LoadViewState(state);
+        }
+
+        /// <internalonly/>
+        void IStateManager.TrackViewState() {
+            TrackViewState();
+        }
+
+        /// <internalonly/>
+        object IStateManager.SaveViewState() {
+            return SaveViewState();
+        }
+        #endregion
+    }
+}
+
+