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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.
#region Using declarations
using System.ComponentModel;
using System.Diagnostics;
using System.Windows.Automation.Peers;
using System.Windows.Documents;
using System.Windows.Media;
using System.Windows.Shapes;
#if RIBBON_IN_FRAMEWORK
using Microsoft.Windows.Controls;
#if RIBBON_IN_FRAMEWORK
namespace System.Windows.Controls.Ribbon
#else
namespace Microsoft.Windows.Controls.Ribbon
#endif
{
#else
using Microsoft.Windows.Automation.Peers;
#endif
#endregion
/// <summary>
/// A specialized label that can lay itself out on at most two lines, and
/// also has the ability to display a special Geometry inline with its text.
/// </summary>
[TemplatePart(Name = "PART_TextBlock1", Type = typeof(TextBlock))]
[TemplatePart(Name = "PART_TextBlock2", Type = typeof(TextBlock))]
[TemplatePart(Name = "PART_Path", Type = typeof(Path))]
public class RibbonTwoLineText : Control
{
#region Constructors
static RibbonTwoLineText()
{
Type ownerType = typeof(RibbonTwoLineText);
DefaultStyleKeyProperty.OverrideMetadata(ownerType, new FrameworkPropertyMetadata(ownerType));
FocusableProperty.OverrideMetadata(ownerType, new FrameworkPropertyMetadata(false));
}
#endregion
#region Fields
private TextBlock _textBlock1, _textBlock2;
private Path _path;
#endregion
#region Public Properties
public TextDecorationCollection TextDecorations
{
get { return (TextDecorationCollection)GetValue(TextDecorationsProperty); }
set { SetValue(TextDecorationsProperty, value); }
}
public static readonly DependencyProperty TextDecorationsProperty = TextBlock.TextDecorationsProperty.AddOwner(typeof(RibbonTwoLineText));
public TextEffectCollection TextEffects
{
get { return (TextEffectCollection)GetValue(TextEffectsProperty); }
set { SetValue(TextEffectsProperty, value); }
}
public static readonly DependencyProperty TextEffectsProperty = TextBlock.TextEffectsProperty.AddOwner(typeof(RibbonTwoLineText));
public double BaselineOffset
{
get { return (double)GetValue(BaselineOffsetProperty); }
set { SetValue(BaselineOffsetProperty, value); }
}
public static readonly DependencyProperty BaselineOffsetProperty = TextBlock.BaselineOffsetProperty.AddOwner(typeof(RibbonTwoLineText));
new public Thickness Padding
{
get { return (Thickness)GetValue(PaddingProperty); }
set { SetValue(PaddingProperty, value); }
}
new public static readonly DependencyProperty PaddingProperty = TextBlock.PaddingProperty.AddOwner(typeof(RibbonTwoLineText));
/// <summary>
/// Gets or sets the TextAlignment set on the internal text block.
/// </summary>
public TextAlignment TextAlignment
{
get { return (TextAlignment)GetValue(TextAlignmentProperty); }
set { SetValue(TextAlignmentProperty, value); }
}
/// <summary>
/// Adds RibbonTwoLineText as an owner of this property.
/// </summary>
public static readonly DependencyProperty TextAlignmentProperty =
TextBlock.TextAlignmentProperty.AddOwner(typeof(RibbonTwoLineText));
/// <summary>
/// Gets or sets the TextTrimming set on the internal text block.
/// </summary>
public TextTrimming TextTrimming
{
get { return (TextTrimming)GetValue(TextTrimmingProperty); }
set { SetValue(TextTrimmingProperty, value); }
}
/// <summary>
/// Adds RibbonTwoLineText as an owner of this property.
/// </summary>
public static readonly DependencyProperty TextTrimmingProperty =
TextBlock.TextTrimmingProperty.AddOwner(typeof(RibbonTwoLineText));
/// <summary>
/// Gets or sets the LineHeight set on the internal text blocks.
/// </summary>
[TypeConverter(typeof(LengthConverter))]
public double LineHeight
{
get { return (double)GetValue(LineHeightProperty); }
set { SetValue(LineHeightProperty, value); }
}
/// <summary>
/// Adds RibbonTwoLineText as an owner of this property.
/// </summary>
public static readonly DependencyProperty LineHeightProperty =
TextBlock.LineHeightProperty.AddOwner(typeof(RibbonTwoLineText));
/// <summary>
/// Gets or sets the LineStackingStrategy set on the internal text blocks.
/// </summary>
public LineStackingStrategy LineStackingStrategy
{
get { return (LineStackingStrategy)GetValue(LineStackingStrategyProperty); }
set { SetValue(LineStackingStrategyProperty, value); }
}
/// <summary>
/// Adds RibbonTwoLineText as an owner of this property.
/// </summary>
public static readonly DependencyProperty LineStackingStrategyProperty =
TextBlock.LineStackingStrategyProperty.AddOwner(typeof(RibbonTwoLineText));
/// <summary>
/// Gets or sets the fill of the label's appending geometry.
/// </summary>
public Brush PathFill
{
get { return (Brush)GetValue(PathFillProperty); }
set { SetValue(PathFillProperty, value); }
}
/// <summary>
/// Using a DependencyProperty as the backing store for PathFillProperty. This enables animation, styling, binding, etc...
/// </summary>
public static readonly DependencyProperty PathFillProperty =
DependencyProperty.Register(
"PathFill",
typeof(Brush),
typeof(RibbonTwoLineText),
null);
/// <summary>
/// Gets or sets the fill of the label's appending geometry.
/// </summary>
public Brush PathStroke
{
get { return (Brush)GetValue(PathStrokeProperty); }
set { SetValue(PathStrokeProperty, value); }
}
/// <summary>
/// Using a DependencyProperty as the backing store for PathStrokeProperty. This enables animation, styling, binding, etc...
/// </summary>
public static readonly DependencyProperty PathStrokeProperty =
DependencyProperty.Register(
"PathStroke",
typeof(Brush),
typeof(RibbonTwoLineText),
null);
/// <summary>
/// Gets or sets the label's text.
/// </summary>
public string Text
{
get { return (string)GetValue(TextProperty); }
set { SetValue(TextProperty, value); }
}
/// <summary>
/// Using a DependencyProperty as the backing store for TextProperty. This enables animation, styling, binding, etc...
/// </summary>
public static readonly DependencyProperty TextProperty =
TextBlock.TextProperty.AddOwner(typeof(RibbonTwoLineText),
new FrameworkPropertyMetadata(string.Empty, FrameworkPropertyMetadataOptions.AffectsMeasure));
/// <summary>
/// Defines Path data for the label's appending Geometry.
/// </summary>
public static readonly DependencyProperty PathDataProperty =
DependencyProperty.RegisterAttached(
"PathData",
typeof(Geometry),
typeof(RibbonTwoLineText),
new FrameworkPropertyMetadata(null, FrameworkPropertyMetadataOptions.AffectsMeasure | FrameworkPropertyMetadataOptions.AffectsRender));
public static Geometry GetPathData(DependencyObject element)
{
ArgumentNullException.ThrowIfNull(element);
return (Geometry)element.GetValue(PathDataProperty);
}
public static void SetPathData(DependencyObject element, Geometry value)
{
ArgumentNullException.ThrowIfNull(element);
element.SetValue(PathDataProperty, value);
}
/// <summary>
/// Using a DependencyProperty as the backing store for HasTwoLinesProperty. This enables animation, styling, binding, etc...
/// </summary>
public static readonly DependencyProperty HasTwoLinesProperty
= DependencyProperty.RegisterAttached("HasTwoLines",
typeof(bool),
typeof(RibbonTwoLineText),
new FrameworkPropertyMetadata(false, FrameworkPropertyMetadataOptions.AffectsMeasure));
/// <summary>
/// Gets or sets a value indicating whether the RibbonTwoLineText should be allowed to
/// layout on two lines or if it should be restricted to one.
/// </summary>
public static bool GetHasTwoLines(DependencyObject element)
{
ArgumentNullException.ThrowIfNull(element);
return (bool)element.GetValue(HasTwoLinesProperty);
}
public static void SetHasTwoLines(DependencyObject element, bool value)
{
ArgumentNullException.ThrowIfNull(element);
element.SetValue(HasTwoLinesProperty, value);
}
#endregion
#region Protected Methods
public override void OnApplyTemplate()
{
base.OnApplyTemplate();
_textBlock1 = this.GetTemplateChild("PART_TextBlock1") as TextBlock;
_textBlock2 = this.GetTemplateChild("PART_TextBlock2") as TextBlock;
_path = this.GetTemplateChild("PART_Path") as Path;
}
protected override Size MeasureOverride(Size availableSize)
{
if (_textBlock1 != null && _textBlock2 != null && _path != null)
{
bool hasTwoLines = GetHasTwoLines(this);
if (!hasTwoLines)
{
// Collapse first line
_textBlock1.Text = null;
_textBlock1.Visibility = Visibility.Collapsed;
// All text shown in second line
_textBlock2.Text = this.Text;
_textBlock2.Visibility = Visibility.Visible;
// Mark measure dirty all UIElements in the visual tree from _textBlock2 upto RibbonTwoLineText
TreeHelper.InvalidateMeasureForVisualAncestorPath<RibbonTwoLineText>(_textBlock2);
}
else // HasTwoLines
{
// Querying the ContentStart property for the very first time has a potential of invalidating
// measure on the TextBlock. So we want to do this once before we call Measure and Arrange to
// guarantee valid layout
TextPointer secondLinePointer = _textBlock1.ContentStart;
// Determine LineBreak with availableSize
MeasureWithConstraint(availableSize, out secondLinePointer);
if (secondLinePointer == null)
{
MeasureWithoutConstraint(out secondLinePointer);
}
if (secondLinePointer != null)
{
// We need to split Text manually
string firstLineText = secondLinePointer.GetTextInRun(LogicalDirection.Backward);
string secondLineText = secondLinePointer.GetTextInRun(LogicalDirection.Forward);
// Display first line in full
_textBlock1.Text = firstLineText;
_textBlock1.Visibility = Visibility.Visible;
// remaining text in second line. Trimming will be applied if TextTrimming is set,
// or else extra text will be clipped.
_textBlock2.Text = secondLineText;
_textBlock2.Visibility = Visibility.Visible;
// Mark measure dirty all UIElements in the visual tree from _textBlock2 upto RibbonTwoLineText
TreeHelper.InvalidateMeasureForVisualAncestorPath<RibbonTwoLineText>(_textBlock2);
}
else
{
// Text is small enough to be displayed in first line alone
_textBlock1.Text = this.Text;
_textBlock1.Visibility = Visibility.Visible;
// Collapse second line
_textBlock2.Text = null;
_textBlock2.Visibility = Visibility.Collapsed;
}
}
}
return base.MeasureOverride(availableSize);
}
/// <summary>
/// Layout Text into two lines when width is restricted and determine if a LineBreak occurs.
/// </summary>
/// <param name="availableSize">constraint</param>
/// <param name="secondLinePointer">TextPointer to where a LineBreak occurs</param>
private void MeasureWithConstraint(Size availableSize, out TextPointer secondLinePointer)
{
Debug.Assert(_textBlock1 != null && _textBlock2 != null);
// Temporarily assign _textBlock1.Text to measure the length it would require
_textBlock1.Text = this.Text;
_textBlock1.TextWrapping = TextWrapping.WrapWithOverflow;
_textBlock1.Visibility = Visibility.Visible;
secondLinePointer = null;
_textBlock1.Measure(availableSize);
// Dev11 Bug 65031 - Text: Invariant Assert hit in TextBlock due to loss of precision error
// Under very rare cases, a loss of precision due to the UseLayoutRounding feature may
// occur on 64-bit systems that can mean the difference between rounding and not.
//
// To work around this, we augment up _textBlock1's DesiredSize.Width by 0.5 pixels
// before arranging it. This is safe, because this measure/arrange pass justs determines
// what should go on the second line of the TwoLineText and is not the actual measure/arrange.
Size bufferedSize = new Size(_textBlock1.DesiredSize.Width + 0.5,
_textBlock1.DesiredSize.Height);
_textBlock1.Arrange(new Rect(bufferedSize));
secondLinePointer = _textBlock1.ContentStart.GetLineStartPosition(1);
// Clear local value
_textBlock1.ClearValue(TextBlock.TextWrappingProperty);
}
/// <summary>
/// Layout Text into two lines without any constraint and determine if a LineBreak occurs.
/// </summary>
/// <param name="secondLinePointer">TextPointer to where a LineBreak occurs</param>
private void MeasureWithoutConstraint(out TextPointer secondLinePointer)
{
Debug.Assert(_textBlock1 != null && _textBlock2 != null);
secondLinePointer = null;
// Temporarily assign _textBlock1.Text to measure the length it would require
_textBlock1.Text = this.Text;
_textBlock1.TextWrapping = TextWrapping.WrapWithOverflow;
_textBlock1.Visibility = Visibility.Visible;
// This measures the TextBlock with infinite bounds to see what its ideal
// (one-line) Width would be. If this width is greater than the minimum
// width for the label, we try halving its site to
// spread the label to two lines.
Size infinity = new Size(double.PositiveInfinity, double.PositiveInfinity);
_textBlock1.Measure(infinity);
double width = _textBlock1.DesiredSize.Width;
int wordCount = string.IsNullOrEmpty(Text) ? 0 : Text.Split().Length;
if ( wordCount > 1)
{
// Set the TextBlock's width to half of its desired with to spread it
// to two lines, and re-run layout.
_textBlock1.Width = Math.Max(1.0, width / 2.0);
_textBlock1.Measure(infinity);
_textBlock1.Arrange(new Rect(_textBlock1.DesiredSize));
// If text flows into more than 2 lines
TextPointer currentLinePointer = _textBlock1.ContentStart.GetLineStartPosition(2);
if (currentLinePointer != null)
{
double extraLength = 0.0;
Rect lastCharacter, firstCharacter;
// Iterate through 3rd to (n-1)th line and add up their lengths.
TextPointer nextLinePointer = currentLinePointer.GetLineStartPosition(1);
while (nextLinePointer != null)
{
lastCharacter = nextLinePointer.GetCharacterRect(LogicalDirection.Backward);
firstCharacter = currentLinePointer.GetCharacterRect(LogicalDirection.Forward);
extraLength += Math.Abs(lastCharacter.X - firstCharacter.X);
currentLinePointer = nextLinePointer;
nextLinePointer = nextLinePointer.GetLineStartPosition(1);
}
// Add length of last line
lastCharacter = _textBlock1.ContentEnd.GetCharacterRect(LogicalDirection.Backward);
firstCharacter = currentLinePointer.GetCharacterRect(LogicalDirection.Forward);
extraLength += Math.Abs(lastCharacter.X - firstCharacter.X);
// Redistribute the extraLength among first two lines
_textBlock1.Width = _textBlock1.Width + extraLength / 2;
_textBlock1.Measure(infinity);
_textBlock1.Arrange(new Rect(_textBlock1.DesiredSize));
}
secondLinePointer = _textBlock1.ContentStart.GetLineStartPosition(1);
// Clear the temporarily assigned values
_textBlock1.ClearValue(TextBlock.WidthProperty);
}
_textBlock1.ClearValue(TextBlock.TextWrappingProperty);
}
protected override AutomationPeer OnCreateAutomationPeer()
{
return new RibbonTwoLineTextAutomationPeer(this);
}
#endregion
}
}
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