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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
//
// Description: Implements a List element, a container for ListElementItems: '
// block elements designed to be formatted with markers such as
// bullets and numbering.
//
using System.ComponentModel;
using System.Windows.Markup;
using MS.Internal;
using MS.Internal.PtsHost.UnsafeNativeMethods; // PTS restrictions
namespace System.Windows.Documents
{
/// <summary>
/// Implements a List element, a container for ListItems: block
/// elements designed to be formatted with markers such as bullets and
/// numbering.
/// </summary>
[ContentProperty("ListItems")]
public class List : Block
{
//-------------------------------------------------------------------
//
// Constructors
//
//-------------------------------------------------------------------
#region Constructors
/// <summary>
/// List static constructor. Registers metadata for its properties.
/// </summary>
static List()
{
DefaultStyleKeyProperty.OverrideMetadata(typeof(List), new FrameworkPropertyMetadata(typeof(List)));
}
/// <summary>
/// Initializes a new instance of a List class.
/// </summary>
public List()
: base()
{
}
/// <summary>
/// Initializes a new instance of a List class specifying its first ListItem child.
/// </summary>
/// <param name="listItem">
/// ListItem to be inserted as a first child of this List.
/// </param>
public List(ListItem listItem)
: base()
{
ArgumentNullException.ThrowIfNull(listItem);
this.ListItems.Add(listItem);
}
#endregion Constructors
//-------------------------------------------------------------------
//
// Public Properties
//
//-------------------------------------------------------------------
#region Public Properties
/// <value>
/// Collection of ListItems contained in this List.
/// </value>
[DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
public ListItemCollection ListItems
{
get
{
return new ListItemCollection(this, /*isOwnerParent*/true);
}
}
/// <summary>
/// DependencyProperty for <see cref="MarkerStyle" /> property.
/// </summary>
public static readonly DependencyProperty MarkerStyleProperty =
DependencyProperty.Register(
"MarkerStyle",
typeof(TextMarkerStyle),
typeof(List),
new FrameworkPropertyMetadata(
TextMarkerStyle.Disc,
FrameworkPropertyMetadataOptions.AffectsMeasure | FrameworkPropertyMetadataOptions.AffectsRender),
new ValidateValueCallback(IsValidMarkerStyle));
/// <summary>
/// Type of bullet or number to be used by default with ListElementItems
/// contained by this List
/// </summary>
public TextMarkerStyle MarkerStyle
{
get { return (TextMarkerStyle)GetValue(MarkerStyleProperty); }
set { SetValue(MarkerStyleProperty, value); }
}
/// <summary>
/// DependencyProperty for <see cref="MarkerOffset" /> property.
/// </summary>
public static readonly DependencyProperty MarkerOffsetProperty =
DependencyProperty.Register(
"MarkerOffset",
typeof(double),
typeof(List),
new FrameworkPropertyMetadata(
Double.NaN,
FrameworkPropertyMetadataOptions.AffectsMeasure | FrameworkPropertyMetadataOptions.AffectsRender),
new ValidateValueCallback(IsValidMarkerOffset));
/// <summary>
/// Desired distance between each contained ListItem's content and
/// near edge of the associated marker.
/// </summary>
[TypeConverter(typeof(LengthConverter))]
public double MarkerOffset
{
get { return (double)GetValue(MarkerOffsetProperty); }
set { SetValue(MarkerOffsetProperty, value); }
}
/// <summary>
/// DependencyProperty for <see cref="StartIndex" /> property.
/// </summary>
public static readonly DependencyProperty StartIndexProperty =
DependencyProperty.Register(
"StartIndex",
typeof(int),
typeof(List),
new FrameworkPropertyMetadata(
1,
FrameworkPropertyMetadataOptions.AffectsMeasure | FrameworkPropertyMetadataOptions.AffectsRender),
new ValidateValueCallback(IsValidStartIndex));
/// <summary>
/// Item index of the first ListItem that is immediate child of
/// this List.
/// </summary>
public int StartIndex
{
get { return (int)GetValue(StartIndexProperty); }
set { SetValue(StartIndexProperty, value); }
}
#endregion Public Properties
//-------------------------------------------------------------------
//
// Internal Methods
//
//-------------------------------------------------------------------
#region Internal Methods
/// <summary>
/// Returns the integer "index" of a specified ListItem that is an immediate child of
/// this List. This index is defined to be a sequential counter of ListElementItems only
/// (skipping other elements) among this List's immediate children.
///
/// The list item index of the first child of type ListItem is specified by
/// this.StartListIndex, which has a default value of 1.
///
/// The index returned by this method is used in the formation of some ListItem
/// markers such as "(b)" and "viii." (as opposed to others, like disks and wedges,
/// which are not sequential-position-dependent).
/// </summary>
/// <param name="item">The item whose index is to be returned.</param>
/// <returns>Returns the index of a specified ListItem.</returns>
internal int GetListItemIndex(ListItem item)
{
// Check for valid arg
ArgumentNullException.ThrowIfNull(item);
if (item.Parent != this)
{
throw new InvalidOperationException(SR.ListElementItemNotAChildOfList);
}
// Count ListItem siblings (not other element types) back to first item.
int itemIndex = StartIndex;
TextPointer textNav = new TextPointer(this.ContentStart);
while (textNav.CompareTo(this.ContentEnd) != 0)
{
// ListItem is a content element, so look for ElementStart runs only
if (textNav.GetPointerContext(LogicalDirection.Forward) == TextPointerContext.ElementStart)
{
DependencyObject element = textNav.GetAdjacentElementFromOuterPosition(LogicalDirection.Forward);
if (element is ListItem)
{
if (element == item)
{
break;
}
if (itemIndex < int.MaxValue)
{
++itemIndex;
}
}
// Skip entire content element content, because we are looking
// only for immediate children.
textNav.MoveToPosition(((TextElement)element).ElementEnd);
}
else
{
textNav.MoveToNextContextPosition(LogicalDirection.Forward);
}
}
return itemIndex;
}
/// <summary>
/// Inserts a List around a sequence of Blocks
/// starting from firstBlock ending with lastBlock.
/// the List must be empty and not inserted in a tree
/// before the operation
/// </summary>
/// <param name="firstBlock"></param>
/// <param name="lastBlock"></param>
internal void Apply(Block firstBlock, Block lastBlock)
{
Invariant.Assert(this.Parent == null, "Cannot Apply List Because It Is Inserted In The Tree Already.");
Invariant.Assert(this.IsEmpty, "Cannot Apply List Because It Is Not Empty.");
Invariant.Assert(firstBlock.Parent == lastBlock.Parent, "Cannot Apply List Because Block Are Not Siblings.");
TextContainer textContainer = this.TextContainer;
textContainer.BeginChange();
try
{
// Wrap all block items into this List element
this.Reposition(firstBlock.ElementStart, lastBlock.ElementEnd);
// Add ListItem elements
Block block = firstBlock;
while (block != null)
{
ListItem listItem;
if (block is List)
{
// To wrap List into list item we pull it into previous ListItem (if any) as sublist
listItem = block.ElementStart.GetAdjacentElement(LogicalDirection.Backward) as ListItem;
if (listItem != null)
{
// Wrap the List into preceding ListItem
listItem.Reposition(listItem.ContentStart, block.ElementEnd);
}
else
{
// No preceding ListItem. Create new one
listItem = new ListItem();
listItem.Reposition(block.ElementStart, block.ElementEnd);
}
}
else
{
// To wrap paragraph into list item we need to create a new one
// Decide what to do with other blocks: Table, Section
listItem = new ListItem();
listItem.Reposition(block.ElementStart, block.ElementEnd);
// MS Word-like heuristic: clear margin from a paragraph before wrapping it into a list item
// Note: using TextContainer to make sure that undo unit is created.
block.ClearValue(Block.MarginProperty);
block.ClearValue(Block.PaddingProperty);
block.ClearValue(Paragraph.TextIndentProperty);
}
// Stop when the last paragraph is covered
block = block == lastBlock ? null : (Block)listItem.ElementEnd.GetAdjacentElement(LogicalDirection.Forward);
}
// We need to set appropriate FlowDirection property on the new List and its paragraph children.
// We take the FlowDirection value from the first paragraph's FlowDirection value.
TextRangeEdit.SetParagraphProperty(this.ElementStart, this.ElementEnd,
Paragraph.FlowDirectionProperty, firstBlock.GetValue(Paragraph.FlowDirectionProperty));
}
finally
{
textContainer.EndChange();
}
}
#endregion Internal Methods
//-------------------------------------------------------------------
//
// Private Methods
//
//-------------------------------------------------------------------
#region Private Methods
private static bool IsValidMarkerStyle(object o)
{
TextMarkerStyle value = (TextMarkerStyle)o;
return value == TextMarkerStyle.None
|| value == TextMarkerStyle.Disc
|| value == TextMarkerStyle.Circle
|| value == TextMarkerStyle.Square
|| value == TextMarkerStyle.Box
|| value == TextMarkerStyle.LowerRoman
|| value == TextMarkerStyle.UpperRoman
|| value == TextMarkerStyle.LowerLatin
|| value == TextMarkerStyle.UpperLatin
|| value == TextMarkerStyle.Decimal;
}
private static bool IsValidStartIndex(object o)
{
int value = (int)o;
return (value > 0);
}
private static bool IsValidMarkerOffset(object o)
{
double value = (double)o;
double maxOffset = Math.Min(1000000, PTS.MaxPageSize);
double minOffset = -maxOffset;
if (Double.IsNaN(value))
{
// Default
return true;
}
if (value < minOffset || value > maxOffset)
{
return false;
}
return true;
}
#endregion Private Methods
}
}
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