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//---------------------------------------------------------------------------
//
// Copyright (C) Microsoft Corporation. All rights reserved.
//
// File: LineProperties.cs
//
// Description: Text line properties provider.
//
// History:
// 04/25/2003 : Microsoft - moving from Avalon branch.
//
//---------------------------------------------------------------------------
using System;
using System.Diagnostics;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Media;
using System.Windows.Media.TextFormatting;
using MS.Internal.Documents;
using MS.Internal.PtsHost; // TextParagraph
namespace MS.Internal.Text
{
// ----------------------------------------------------------------------
// Text line properties provider.
// ----------------------------------------------------------------------
internal class LineProperties : TextParagraphProperties
{
// ------------------------------------------------------------------
//
// TextParagraphProperties Implementation
//
// ------------------------------------------------------------------
#region TextParagraphProperties Implementation
/// <summary>
/// This property specifies whether the primary text advance
/// direction shall be left-to-right, right-to-left, or top-to-bottom.
/// </summary>
public override FlowDirection FlowDirection { get { return _flowDirection; } }
/// <summary>
/// This property describes how inline content of a block is aligned.
/// </summary>
public override TextAlignment TextAlignment { get { return IgnoreTextAlignment ? TextAlignment.Left : _textAlignment; } }
/// <summary>
/// Paragraph's line height
/// </summary>
/// <remarks>
/// TextFormatter does not do appropriate line height handling, so
/// report always 0 as line height.
/// Line height is handled by TextFormatter host.
/// </remarks>
public override double LineHeight
{
get
{
if (LineStackingStrategy == LineStackingStrategy.BlockLineHeight && !Double.IsNaN(_lineHeight))
{
return _lineHeight;
}
return 0.0;
}
}
/// <summary>
/// Indicates the first line of the paragraph.
/// </summary>
public override bool FirstLineInParagraph { get { return false; } }
/// <summary>
/// Paragraph's default run properties
/// </summary>
public override TextRunProperties DefaultTextRunProperties { get { return _defaultTextProperties; } }
/// <summary>
/// Text decorations specified at the paragraph level.
/// </summary>
public override TextDecorationCollection TextDecorations { get { return _defaultTextProperties.TextDecorations; } }
/// <summary>
/// This property controls whether or not text wraps when it reaches the flow edge
/// of its containing block box
/// </summary>
public override TextWrapping TextWrapping { get { return _textWrapping; } }
/// <summary>
/// This property specifies marker characteristics of the first line in paragraph
/// </summary>
public override TextMarkerProperties TextMarkerProperties { get { return _markerProperties; } }
/// <summary>
/// Line indentation
/// </summary>
/// <remarks>
/// Line indentation. Line indent by default is always 0.
/// Use FirstLineProperties class to return real value of this property.
/// </remarks>
public override double Indent { get { return 0.0; } }
#endregion TextParagraphProperties Implementation
/// <summary>
/// Constructor.
/// </summary>
internal LineProperties(
DependencyObject element,
DependencyObject contentHost,
TextProperties defaultTextProperties,
MarkerProperties markerProperties)
: this(element, contentHost, defaultTextProperties, markerProperties, (TextAlignment)element.GetValue(Block.TextAlignmentProperty))
{
}
/// <summary>
/// Constructor.
/// </summary>
internal LineProperties(
DependencyObject element,
DependencyObject contentHost,
TextProperties defaultTextProperties,
MarkerProperties markerProperties,
TextAlignment textAlignment)
{
_defaultTextProperties = defaultTextProperties;
_markerProperties = (markerProperties != null) ? markerProperties.GetTextMarkerProperties(this) : null;
_flowDirection = (FlowDirection)element.GetValue(Block.FlowDirectionProperty);
_textAlignment = textAlignment;
_lineHeight = (double)element.GetValue(Block.LineHeightProperty);
_textIndent = (double)element.GetValue(Paragraph.TextIndentProperty);
_lineStackingStrategy = (LineStackingStrategy)element.GetValue(Block.LineStackingStrategyProperty);
_textWrapping = TextWrapping.Wrap;
_textTrimming = TextTrimming.None;
if (contentHost is TextBlock || contentHost is ITextBoxViewHost)
{
// NB: we intentially don't try to find the "PropertyOwner" of
// a FlowDocument here. TextWrapping has a hard-coded
// value SetValue'd when a FlowDocument is hosted by a TextBoxBase.
_textWrapping = (TextWrapping)contentHost.GetValue(TextBlock.TextWrappingProperty);
_textTrimming = (TextTrimming)contentHost.GetValue(TextBlock.TextTrimmingProperty);
}
else if (contentHost is FlowDocument)
{
_textWrapping = ((FlowDocument)contentHost).TextWrapping;
}
}
/// <summary>
/// Calculate line advance for TextParagraphs - this method has special casing in case the LineHeight property on the Paragraph element
/// needs to be respected
/// </summary>
/// <param name="textParagraph">
/// TextParagraph that owns the line
/// </param>
/// <param name="dcp">
/// Dcp of the line
/// </param>
/// <param name="lineAdvance">
/// Calculated height of the line
/// </param>
internal double CalcLineAdvanceForTextParagraph(TextParagraph textParagraph, int dcp, double lineAdvance)
{
if (!DoubleUtil.IsNaN(_lineHeight))
{
switch (LineStackingStrategy)
{
case LineStackingStrategy.BlockLineHeight:
lineAdvance = _lineHeight;
break;
case LineStackingStrategy.MaxHeight:
default:
if (dcp == 0 && textParagraph.HasFiguresOrFloaters() &&
((textParagraph.GetLastDcpAttachedObjectBeforeLine(0) + textParagraph.ParagraphStartCharacterPosition)
== textParagraph.ParagraphEndCharacterPosition))
{
// The Paragraph element contains only figures and floaters and has LineHeight set. In this case LineHeight
// should be respected
lineAdvance = _lineHeight;
}
else
{
lineAdvance = Math.Max(lineAdvance, _lineHeight);
}
break;
// case LineStackingStrategy.InlineLineHeight:
// // Inline uses the height of the line just processed.
// break;
// case LineStackingStrategy.GridHeight:
// lineAdvance = (((TextDpi.ToTextDpi(lineAdvance) - 1) / TextDpi.ToTextDpi(_lineHeight)) + 1) * _lineHeight;
// break;
//}
}
}
return lineAdvance;
}
/// <summary>
/// Calculate line advance from actual line height and the line stacking strategy.
/// </summary>
internal double CalcLineAdvance(double lineAdvance)
{
// We support MaxHeight and BlockLineHeight stacking strategies
if (!DoubleUtil.IsNaN(_lineHeight))
{
switch (LineStackingStrategy)
{
case LineStackingStrategy.BlockLineHeight:
lineAdvance = _lineHeight;
break;
case LineStackingStrategy.MaxHeight:
default:
lineAdvance = Math.Max(lineAdvance, _lineHeight);
break;
// case LineStackingStrategy.InlineLineHeight:
// // Inline uses the height of the line just processed.
// break;
// case LineStackingStrategy.GridHeight:
// lineAdvance = (((TextDpi.ToTextDpi(lineAdvance) - 1) / TextDpi.ToTextDpi(_lineHeight)) + 1) * _lineHeight;
// break;
//}
}
}
return lineAdvance;
}
/// <summary>
/// Raw TextAlignment, without considering IgnoreTextAlignment.
/// </summary>
internal TextAlignment TextAlignmentInternal
{
get
{
return _textAlignment;
}
}
/// <summary>
/// Ignore text alignment?
/// </summary>
internal bool IgnoreTextAlignment
{
get { return _ignoreTextAlignment; }
set { _ignoreTextAlignment = value; }
}
///// <summary>
///// Line stacking strategy.
///// </summary>
internal LineStackingStrategy LineStackingStrategy
{
get { return _lineStackingStrategy; }
}
/// <summary>
/// Text trimming.
/// </summary>
internal TextTrimming TextTrimming
{
get { return _textTrimming; }
}
/// <summary>
/// Does it have first line specific properties?
/// </summary>
internal bool HasFirstLineProperties
{
get { return (_markerProperties != null || !DoubleUtil.IsZero(_textIndent)); }
}
/// <summary>
/// Local cache for first line properties.
/// </summary>
internal TextParagraphProperties FirstLineProps
{
get
{
if (_firstLineProperties == null)
{
_firstLineProperties = new FirstLineProperties(this);
}
return _firstLineProperties;
}
}
// ------------------------------------------------------------------
// Local cache for line properties with paragraph ellipsis.
// ------------------------------------------------------------------
/// <summary>
/// Local cache for line properties with paragraph ellipsis.
/// </summary>
internal TextParagraphProperties GetParaEllipsisLineProps(bool firstLine)
{
return new ParaEllipsisLineProperties(firstLine ? FirstLineProps : this);
}
private TextRunProperties _defaultTextProperties; // Line's default text properties.
private TextMarkerProperties _markerProperties; // Marker properties
private FirstLineProperties _firstLineProperties; // Local cache for first line properties.
private bool _ignoreTextAlignment; // Ignore horizontal alignment?
private FlowDirection _flowDirection;
private TextAlignment _textAlignment;
private TextWrapping _textWrapping;
private TextTrimming _textTrimming;
private double _lineHeight;
private double _textIndent;
private LineStackingStrategy _lineStackingStrategy;
// ----------------------------------------------------------------------
// First text line properties provider.
// ----------------------------------------------------------------------
private sealed class FirstLineProperties : TextParagraphProperties
{
// ------------------------------------------------------------------
//
// TextParagraphProperties Implementation
//
// ------------------------------------------------------------------
#region TextParagraphProperties Implementation
// ------------------------------------------------------------------
// Text flow direction (text advance + block advance direction).
// ------------------------------------------------------------------
public override FlowDirection FlowDirection { get { return _lp.FlowDirection; } }
// ------------------------------------------------------------------
// Alignment of the line's content.
// ------------------------------------------------------------------
public override TextAlignment TextAlignment { get { return _lp.TextAlignment; } }
// ------------------------------------------------------------------
// Line's height.
// ------------------------------------------------------------------
public override double LineHeight { get { return _lp.LineHeight; } }
// ------------------------------------------------------------------
// An instance of this class is always the first line in a paragraph.
// ------------------------------------------------------------------
public override bool FirstLineInParagraph { get { return true; } }
// ------------------------------------------------------------------
// Line's default text properties.
// ------------------------------------------------------------------
public override TextRunProperties DefaultTextRunProperties { get { return _lp.DefaultTextRunProperties; } }
// ------------------------------------------------------------------
// Line's text decorations (in addition to any run-level text decorations).
// ------------------------------------------------------------------
public override TextDecorationCollection TextDecorations { get { return _lp.TextDecorations; } }
// ------------------------------------------------------------------
// Text wrap control.
// ------------------------------------------------------------------
public override TextWrapping TextWrapping { get { return _lp.TextWrapping; } }
// ------------------------------------------------------------------
// Marker characteristics of the first line in paragraph.
// ------------------------------------------------------------------
public override TextMarkerProperties TextMarkerProperties { get { return _lp.TextMarkerProperties; } }
// ------------------------------------------------------------------
// Line indentation.
// ------------------------------------------------------------------
public override double Indent { get { return _lp._textIndent; } }
#endregion TextParagraphProperties Implementation
// ------------------------------------------------------------------
// Constructor.
// ------------------------------------------------------------------
internal FirstLineProperties(LineProperties lp)
{
_lp = lp;
// properly set the local copy of hyphenator accordingly.
Hyphenator = lp.Hyphenator;
}
// ------------------------------------------------------------------
// LineProperties object reference.
// ------------------------------------------------------------------
private LineProperties _lp;
}
// ----------------------------------------------------------------------
// Line properties provider for line with paragraph ellipsis.
// ----------------------------------------------------------------------
private sealed class ParaEllipsisLineProperties : TextParagraphProperties
{
// ------------------------------------------------------------------
//
// TextParagraphProperties Implementation
//
// ------------------------------------------------------------------
#region TextParagraphProperties Implementation
// ------------------------------------------------------------------
// Text flow direction (text advance + block advance direction).
// ------------------------------------------------------------------
public override FlowDirection FlowDirection { get { return _lp.FlowDirection; } }
// ------------------------------------------------------------------
// Alignment of the line's content.
// ------------------------------------------------------------------
public override TextAlignment TextAlignment { get { return _lp.TextAlignment; } }
// ------------------------------------------------------------------
// Line's height.
// ------------------------------------------------------------------
public override double LineHeight { get { return _lp.LineHeight; } }
// ------------------------------------------------------------------
// First line in paragraph option.
// ------------------------------------------------------------------
public override bool FirstLineInParagraph { get { return _lp.FirstLineInParagraph; } }
// ------------------------------------------------------------------
// Always collapsible option.
// ------------------------------------------------------------------
public override bool AlwaysCollapsible { get { return _lp.AlwaysCollapsible; } }
// ------------------------------------------------------------------
// Line's default text properties.
// ------------------------------------------------------------------
public override TextRunProperties DefaultTextRunProperties { get { return _lp.DefaultTextRunProperties; } }
// ------------------------------------------------------------------
// Line's text decorations (in addition to any run-level text decorations).
// ------------------------------------------------------------------
public override TextDecorationCollection TextDecorations { get { return _lp.TextDecorations; } }
// ------------------------------------------------------------------
// Text wrap control.
// If paragraph ellipsis are enabled, force this line not to wrap.
// ------------------------------------------------------------------
public override TextWrapping TextWrapping { get { return TextWrapping.NoWrap; } }
// ------------------------------------------------------------------
// Marker characteristics of the first line in paragraph.
// ------------------------------------------------------------------
public override TextMarkerProperties TextMarkerProperties { get { return _lp.TextMarkerProperties; } }
// ------------------------------------------------------------------
// Line indentation.
// ------------------------------------------------------------------
public override double Indent { get { return _lp.Indent; } }
#endregion TextParagraphProperties Implementation
// ------------------------------------------------------------------
// Constructor.
// ------------------------------------------------------------------
internal ParaEllipsisLineProperties(TextParagraphProperties lp)
{
_lp = lp;
}
// ------------------------------------------------------------------
// LineProperties object reference.
// ------------------------------------------------------------------
private TextParagraphProperties _lp;
}
}
}
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