1 /*

     2 * Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies). 

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 * 

    14 * Description:

    15 *

    16 */

    17 using System;

    18 using System.Collections.Generic;

    19 

    20 namespace SymbianUtils.Settings

    21 {

    22 	public class XmlSettingsBoundedList

    23 	{

    24 		#region Constructors

    25 		public XmlSettingsBoundedList( string aCategory, XmlSettings aSettings )

    26 		{

    27 			// Since the max capacity was not supplied, we can attempt to read

    28 			// it from the settings or then if not found, we default to 10.

    29 			iSettings = aSettings;

    30 			iCategory = aCategory;

    31 			iMaxCapacity = SettingsMaxCapacity;

    32 			//

    33 			Restore();

    34 		}

    35 

    36 		public XmlSettingsBoundedList( string aCategory, XmlSettings aSettings, int aMaxCapacity )

    37 		{

    38 			iSettings = aSettings;

    39 			iCategory = aCategory;

    40 			iMaxCapacity = aMaxCapacity;

    41 			//

    42 			Restore();

    43 		}

    44 		#endregion

    45 

    46 		#region API

    47 		public void Restore()

    48 		{

    49 			// Newest additions are stored at the front of the list.

    50 			// Oldest items are therefore at the end

    51 			iList.Clear();

    52 			//

    53 			int settingsCount = SettingsCount;

    54             for ( int i = 0; i < settingsCount && i < MaxCapacity; i++ )

    55 			{

    56 				string item = SettingItem(i);

    57 				iList.Add( item );

    58 			}

    59 		}

    60 

    61 		public void Store()

    62 		{

    63 			// Remove all entries that already exist

    64 			// within the settings object

    65 			RemoveAllExistingSettings();

    66 

    67 			// Now add the replacement items

    68 			int settingsCount = iList.Count;

    69 			SettingsCount = settingsCount;

    70 			for(int i=0; i<settingsCount; i++)

    71 			{

    72 				string itemKey = MakeSettingsKey( i );

    73 				string itemValue = iList[ i ];

    74 				//

    75 				iSettings[ Category, itemKey ] = itemValue;

    76 			}

    77 		}

    78 

    79 		public void Add( string aValue )

    80 		{

    81 			// First, add the item

    82 			iList.Insert( 0, aValue );

    83 

    84 			// If the capacity has reached the limit, we remove the last (oldest) item

    85 			if	( iList.Count > MaxCapacity )

    86 			{

    87 				iList.RemoveAt( MaxCapacity );

    88 			}

    89 		}

    90 		#endregion

    91 

    92 		#region Properties

    93 		public int MaxCapacity

    94 		{

    95 			get { return iMaxCapacity; }

    96 		}

    97 

    98 		public string Category

    99 		{

   100 			get { return iCategory; }

   101 		}

   102 

   103 		public int Count

   104 		{

   105 			get { return iList.Count; }

   106 		}

   107 		#endregion

   108 

   109 		#region Internal properties

   110 		private int SettingsCount

   111 		{

   112 			get

   113 			{

   114 				int count = 0;

   115 				string countAsString = iSettings[Category, "_NumberOfItems"];

   116 				if	(countAsString != null)

   117 				{

   118 					count = System.Convert.ToInt32(countAsString);

   119 				}

   120 				return count;

   121 			}

   122 			set

   123 			{

   124 				iSettings[Category, "_NumberOfItems"] = value.ToString();

   125 			}

   126 		}

   127 

   128 		private int SettingsMaxCapacity

   129 		{

   130 			get

   131 			{

   132 				int capacity = 0;

   133 				string capacityAsString = iSettings[Category, "_MaxCapacity"];

   134 				if	(capacityAsString != null)

   135 				{

   136 					capacity = System.Convert.ToInt32(capacityAsString);

   137 				}

   138 				return capacity;

   139 			}

   140 			set

   141 			{

   142 				iSettings[Category, "_MaxCapacity"] = value.ToString();

   143 			}

   144 		}

   145 		#endregion

   146 

   147 		#region Internal methods

   148 		private string MakeSettingsKey( int aIndex )

   149 		{

   150 			return "_Entry_Id_" + aIndex.ToString( "0000" );

   151 		}

   152 

   153 		private string SettingItem( int aIndex )

   154 		{

   155 			string key = MakeSettingsKey( aIndex );

   156 			string itemValue = iSettings[ Category, key ];

   157 			//

   158 			return itemValue;

   159 		}

   160 

   161 		private void RemoveAllExistingSettings()

   162 		{

   163 			iSettings.Remove( Category );

   164 		}

   165 		#endregion

   166 

   167 		#region Data members

   168 		int iMaxCapacity = 100;

   169 		readonly string iCategory;

   170 		readonly XmlSettings iSettings;

   171 		List<string> iList = new List<string>(10);

   172 		#endregion

   173 	}

   174 }