public virtual void OrphansWidowsAwareAndDirectLayoutProduceSameResult()
{
PdfDocument pdfDocument = new PdfDocument(new PdfWriter(new MemoryStream()));
Document document = new Document(pdfDocument);
int minAllowedWidows = 3;
int overflowedToNextPageLinesNum = 5;
Paragraph widowsParagraph = new Paragraph(OrphansWidowsTestUtil.PARA_TEXT);
IRenderer paragraphRenderer = widowsParagraph.CreateRendererSubTree().SetParent(document.GetRenderer());
Rectangle effectiveArea = document.GetPageEffectiveArea(pdfDocument.GetDefaultPageSize());
float linesHeight = OrphansWidowsTestUtil.CalculateHeightForLinesNum(document, widowsParagraph, effectiveArea
.GetWidth(), overflowedToNextPageLinesNum, false);
Rectangle layoutAreaRect = new Rectangle(effectiveArea).SetHeight(linesHeight + OrphansWidowsTestUtil.LINES_SPACE_EPS
);
LayoutContext layoutContext = new LayoutContext(new LayoutArea(1, layoutAreaRect));
LayoutResult noWidowsControlLayoutResult = paragraphRenderer.Layout(layoutContext);
ParagraphWidowsControl widowsControl = new ParagraphWidowsControl(minAllowedWidows, 1, false);
widowsParagraph.SetWidowsControl(widowsControl);
LayoutResult widowsControlLayoutResult = paragraphRenderer.Layout(layoutContext);
// toString() comparison is used since it contains report on status, areaBreak and occupiedArea
NUnit.Framework.Assert.AreEqual(noWidowsControlLayoutResult.ToString(), widowsControlLayoutResult.ToString
());
ParagraphRenderer firstSplitRenderer = (ParagraphRenderer)noWidowsControlLayoutResult.GetSplitRenderer();
ParagraphRenderer secondSplitRenderer = (ParagraphRenderer)widowsControlLayoutResult.GetSplitRenderer();
NUnit.Framework.Assert.IsNotNull(firstSplitRenderer);
NUnit.Framework.Assert.IsNotNull(secondSplitRenderer);
NUnit.Framework.Assert.AreEqual(firstSplitRenderer.ToString(), secondSplitRenderer.ToString());
NUnit.Framework.Assert.IsNotNull(noWidowsControlLayoutResult.GetOverflowRenderer());
NUnit.Framework.Assert.IsNotNull(widowsControlLayoutResult.GetOverflowRenderer());
}
public virtual void WidowsPropertyOneInheritedOneRedefined()
{
IList <IElement> elements = ConvertToElements("widowsPropertyOneInheritedOneRedefined");
Div div = (Div)elements[0];
NUnit.Framework.Assert.IsNotNull(div);
ParagraphWidowsControl divWidowsControl = div.GetProperty <ParagraphWidowsControl>(Property.WIDOWS_CONTROL);
NUnit.Framework.Assert.IsNotNull(divWidowsControl);
NUnit.Framework.Assert.AreEqual(3, divWidowsControl.GetMinWidows());
Paragraph paragraph = (Paragraph)div.GetChildren()[0];
NUnit.Framework.Assert.IsNotNull(paragraph);
ParagraphWidowsControl paragraphWidowsControl = paragraph.GetProperty <ParagraphWidowsControl>(Property.WIDOWS_CONTROL
);
NUnit.Framework.Assert.IsNotNull(paragraphWidowsControl);
NUnit.Framework.Assert.AreEqual(3, paragraphWidowsControl.GetMinWidows());
Paragraph anotherParagraph = (Paragraph)div.GetChildren()[1];
NUnit.Framework.Assert.IsNotNull(anotherParagraph);
ParagraphWidowsControl anotherParagraphWidowsControl = anotherParagraph.GetProperty <ParagraphWidowsControl
>(Property.WIDOWS_CONTROL);
NUnit.Framework.Assert.IsNotNull(anotherParagraphWidowsControl);
NUnit.Framework.Assert.AreEqual(4, anotherParagraphWidowsControl.GetMinWidows());
}
public virtual void OrphansWidowsParallelInheritance()
{
IList <IElement> elements = ConvertToElements("orphansWidowsParallelInheritance");
Div level1Div = (Div)elements[0];
NUnit.Framework.Assert.IsNotNull(level1Div);
ParagraphOrphansControl level1DivOrphansControl = level1Div.GetProperty <ParagraphOrphansControl>(Property.
ORPHANS_CONTROL);
NUnit.Framework.Assert.IsNotNull(level1DivOrphansControl);
NUnit.Framework.Assert.AreEqual(3, level1DivOrphansControl.GetMinOrphans());
ParagraphWidowsControl level1DivWidowsControl = level1Div.GetProperty <ParagraphWidowsControl>(Property.WIDOWS_CONTROL
);
NUnit.Framework.Assert.IsNull(level1DivWidowsControl);
Div level2Div = (Div)level1Div.GetChildren()[0];
NUnit.Framework.Assert.IsNotNull(level2Div);
ParagraphOrphansControl level2DivOrphansControl = level2Div.GetProperty <ParagraphOrphansControl>(Property.
ORPHANS_CONTROL);
NUnit.Framework.Assert.IsNotNull(level2DivOrphansControl);
NUnit.Framework.Assert.AreEqual(3, level2DivOrphansControl.GetMinOrphans());
ParagraphWidowsControl level2DivWidowsControl = level2Div.GetProperty <ParagraphWidowsControl>(Property.WIDOWS_CONTROL
);
NUnit.Framework.Assert.IsNotNull(level2DivWidowsControl);
NUnit.Framework.Assert.AreEqual(5, level2DivWidowsControl.GetMinWidows());
Paragraph paragraph1 = (Paragraph)level2Div.GetChildren()[0];
NUnit.Framework.Assert.IsNotNull(paragraph1);
ParagraphOrphansControl paragraph1OrphansControl = paragraph1.GetProperty <ParagraphOrphansControl>(Property
.ORPHANS_CONTROL);
NUnit.Framework.Assert.IsNotNull(paragraph1OrphansControl);
NUnit.Framework.Assert.AreEqual(3, paragraph1OrphansControl.GetMinOrphans());
ParagraphWidowsControl paragraph1WidowsControl = paragraph1.GetProperty <ParagraphWidowsControl>(Property.WIDOWS_CONTROL
);
NUnit.Framework.Assert.IsNotNull(paragraph1WidowsControl);
NUnit.Framework.Assert.AreEqual(5, paragraph1WidowsControl.GetMinWidows());
Paragraph paragraph2 = (Paragraph)level2Div.GetChildren()[1];
NUnit.Framework.Assert.IsNotNull(paragraph2);
ParagraphOrphansControl paragraph2OrphansControl = paragraph2.GetProperty <ParagraphOrphansControl>(Property
.ORPHANS_CONTROL);
NUnit.Framework.Assert.IsNotNull(paragraph2OrphansControl);
NUnit.Framework.Assert.AreEqual(4, paragraph2OrphansControl.GetMinOrphans());
ParagraphWidowsControl paragraph2WidowsControl = paragraph2.GetProperty <ParagraphWidowsControl>(Property.WIDOWS_CONTROL
);
NUnit.Framework.Assert.IsNotNull(paragraph2WidowsControl);
NUnit.Framework.Assert.AreEqual(5, paragraph2WidowsControl.GetMinWidows());
}
public virtual void WidowsPropertyPresent()
{
IList <IElement> elements = ConvertToElements("widowsPropertyPresent");
Paragraph paragraph = (Paragraph)elements[0];
NUnit.Framework.Assert.IsNotNull(paragraph);
ParagraphWidowsControl widowsControl = paragraph.GetProperty <ParagraphWidowsControl>(Property.WIDOWS_CONTROL
);
NUnit.Framework.Assert.IsNotNull(widowsControl);
NUnit.Framework.Assert.AreEqual(3, widowsControl.GetMinWidows());
}
/// <summary><inheritDoc/></summary>
public override LayoutResult Layout(LayoutContext layoutContext)
{
ParagraphOrphansControl orphansControl = this.GetProperty <ParagraphOrphansControl>(Property.ORPHANS_CONTROL
);
ParagraphWidowsControl widowsControl = this.GetProperty <ParagraphWidowsControl>(Property.WIDOWS_CONTROL);
if (orphansControl != null || widowsControl != null)
{
return(OrphansWidowsLayoutHelper.OrphansWidowsAwareLayout(this, layoutContext, orphansControl, widowsControl
));
}
return(DirectLayout(layoutContext));
}
public override void Apply(ProcessorContext context, IStylesContainer stylesContainer, ITagWorker tagWorker
)
{
base.Apply(context, stylesContainer, tagWorker);
Paragraph paragraph = (Paragraph)tagWorker.GetElementResult();
ParagraphWidowsControl widowsControl = paragraph.GetProperty <ParagraphWidowsControl>(Property.WIDOWS_CONTROL
);
if (widowsControl != null)
{
widowsControl.SetMinAllowedWidows(widowsControl.GetMinWidows(), 3, true);
paragraph.SetProperty(Property.WIDOWS_CONTROL, widowsControl);
}
}
public virtual void AlterOrphansWidowsTest()
{
ConverterProperties converterProperties = new ConverterProperties();
DefaultCssApplierFactory cssApplierFactory = new OrphansWidowsUnitTest.CustomBlockCssApplierFactory();
converterProperties.SetCssApplierFactory(cssApplierFactory);
IList <IElement> elements = HtmlConverter.ConvertToElements(new FileStream(sourceFolder + "orphansWidows.html"
, FileMode.Open, FileAccess.Read), converterProperties);
Div div = (Div)elements[0];
NUnit.Framework.Assert.IsNotNull(div);
Paragraph paragraph = (Paragraph)div.GetChildren()[0];
NUnit.Framework.Assert.IsNotNull(paragraph);
ParagraphWidowsControl paragraphWidowsControl = paragraph.GetProperty <ParagraphWidowsControl>(Property.WIDOWS_CONTROL
);
NUnit.Framework.Assert.IsNotNull(paragraphWidowsControl);
NUnit.Framework.Assert.AreEqual(3, paragraphWidowsControl.GetMaxLinesToMove());
NUnit.Framework.Assert.IsTrue(paragraphWidowsControl.IsOverflowOnWidowsViolation());
}
internal static LayoutResult OrphansWidowsAwareLayout(ParagraphRenderer renderer, LayoutContext context, ParagraphOrphansControl
orphansControl, ParagraphWidowsControl widowsControl)
{
OrphansWidowsLayoutHelper.OrphansWidowsLayoutAttempt layoutAttempt = AttemptLayout(renderer, context, context
.GetArea().Clone());
if (context.IsClippedHeight() || renderer.IsPositioned() || layoutAttempt.attemptResult.GetStatus() != LayoutResult
.PARTIAL || layoutAttempt.attemptResult.GetSplitRenderer() == null)
{
return(HandleAttemptAsSuccessful(layoutAttempt, context));
}
ParagraphRenderer splitRenderer = (ParagraphRenderer)layoutAttempt.attemptResult.GetSplitRenderer();
bool orphansViolation = orphansControl != null && splitRenderer != null && splitRenderer.GetLines().Count
< orphansControl.GetMinOrphans() && !renderer.IsFirstOnRootArea();
bool forcedPlacement = true.Equals(renderer.GetPropertyAsBoolean(Property.FORCED_PLACEMENT));
if (orphansViolation && forcedPlacement)
{
orphansControl.HandleViolatedOrphans(splitRenderer, "Ignored orphans constraint due to forced placement.");
}
if (orphansViolation && !forcedPlacement)
{
layoutAttempt = null;
}
else
{
if (widowsControl != null && splitRenderer != null && layoutAttempt.attemptResult.GetOverflowRenderer() !=
null)
{
ParagraphRenderer overflowRenderer = (ParagraphRenderer)layoutAttempt.attemptResult.GetOverflowRenderer();
// Excessively big value to check if widows constraint is violated;
// Make this value less in order to improve performance if you are sure
// that min number of widows will fit in this height. E.g. A4 page height is 842.
int simulationHeight = 3500;
LayoutArea simulationArea = new LayoutArea(context.GetArea().GetPageNumber(), context.GetArea().GetBBox().
Clone().SetHeight(simulationHeight));
// collapsingMarginsInfo might affect available space, which is redundant in case we pass arbitrary space.
// floatedRendererAreas list on new area is considered empty. We don't know if there will be any, however their presence in any case will result in more widows, not less.
// clippedHeight is undefined for the next area, because it is defined by overflow part of the paragraph parent.
// Even if it will be set to true in actual overflow-part layouting, stealing lines approach will result in
// giving bigger part of MAX-HEIGHT to the overflow part and resulting in bigger number of widows, which is better.
// However for possible other approaches which change content "length" (like word/char spacing adjusts),
// if in actual overflow-part layouting clippedHeight will be true, those widows fixing attempts will result in worse results.
LayoutContext simulationContext = new LayoutContext(simulationArea);
LayoutResult simulationResult = overflowRenderer.DirectLayout(simulationContext);
if (simulationResult.GetStatus() == LayoutResult.FULL)
{
// simulationHeight is excessively big in order to allow to layout all of the content remaining in overflowRenderer:
// this way after all of the remaining content is layouted we can check if it has led to widows violation.
// To make this analysis possible, we expect to get result FULL.
// if result is PARTIAL: means that simulationHeight value isn't big enough to layout all of the content remaining in overflowRenderer.
// In this case we assume that widows aren't violated since the amount of the lines to fit the simulatedHeight is expected to be very large.
// if result is NOTHING: unexpected result, limitation of simulation approach. Retry again with forced placement set.
int extraWidows = widowsControl.GetMinWidows() - overflowRenderer.GetLines().Count;
if (extraWidows > 0)
{
int extraLinesToMove = orphansControl != null?Math.Max(orphansControl.GetMinOrphans(), 1) : 1;
if (extraWidows <= widowsControl.GetMaxLinesToMove() && splitRenderer.GetLines().Count - extraWidows >= extraLinesToMove
)
{
LineRenderer lastLine = splitRenderer.GetLines()[splitRenderer.GetLines().Count - 1];
LineRenderer lastLineToLeave = splitRenderer.GetLines()[splitRenderer.GetLines().Count - extraWidows - 1];
float d = lastLineToLeave.GetOccupiedArea().GetBBox().GetY() - lastLine.GetOccupiedArea().GetBBox().GetY()
- AbstractRenderer.EPS;
Rectangle smallerBBox = new Rectangle(context.GetArea().GetBBox());
smallerBBox.DecreaseHeight(d);
smallerBBox.MoveUp(d);
LayoutArea smallerAvailableArea = new LayoutArea(context.GetArea().GetPageNumber(), smallerBBox);
layoutAttempt = AttemptLayout(renderer, context, smallerAvailableArea);
}
else
{
if (forcedPlacement || renderer.IsFirstOnRootArea() || !widowsControl.IsOverflowOnWidowsViolation())
{
if (forcedPlacement)
{
widowsControl.HandleViolatedWidows(overflowRenderer, "forced placement");
}
else
{
widowsControl.HandleViolatedWidows(overflowRenderer, "inability to fix it");
}
}
else
{
layoutAttempt = null;
}
}
}
}
}
}
if (layoutAttempt != null)
{
return(HandleAttemptAsSuccessful(layoutAttempt, context));
}
else
{
return(new LayoutResult(LayoutResult.NOTHING, null, null, renderer));
}
}
/// <summary>
/// Sets widows restriction on a
/// <see cref="Paragraph"/>.
/// </summary>
/// <param name="widowsControl">
/// an instance of
/// <see cref="iText.Layout.Properties.ParagraphWidowsControl"/>.
/// </param>
/// <returns>
/// this
/// <see cref="Paragraph"/>
/// instance.
/// </returns>
public virtual iText.Layout.Element.Paragraph SetWidowsControl(ParagraphWidowsControl widowsControl)
{
SetProperty(Property.WIDOWS_CONTROL, widowsControl);
return(this);
}
public virtual void PrematureCallOfHandleViolatedWidows()
{
ParagraphWidowsControl widowsControl = new ParagraphWidowsControl(2, 1, false);
widowsControl.HandleViolatedWidows(new ParagraphRenderer(new Paragraph()), "");
}
