private static YogaSize MeasureText(ReactTextShadowNode textNode, YogaNode node, float width, YogaMeasureMode widthMode, float height, YogaMeasureMode heightMode)
{
// TODO: Measure text with DirectWrite or other API that does not
// require dispatcher access. Currently, we're instantiating a
// second CoreApplicationView (that is never activated) and using
// its Dispatcher thread to calculate layout.
var textBlock = new RichTextBlock
{
TextWrapping = TextWrapping.Wrap,
TextAlignment = TextAlignment.DetectFromContent,
TextTrimming = TextTrimming.CharacterEllipsis,
};
textNode.UpdateTextBlockCore(textBlock, true);
var block = new Paragraph();
for (var i = 0; i < textNode.ChildCount; ++i)
{
var child = textNode.GetChildAt(i);
block.Inlines.Add(ReactInlineShadowNodeVisitor.Apply(child));
}
textBlock.Blocks.Add(block);
var normalizedWidth = YogaConstants.IsUndefined(width) ? double.PositiveInfinity : width;
var normalizedHeight = YogaConstants.IsUndefined(height) ? double.PositiveInfinity : height;
textBlock.Measure(new Size(normalizedWidth, normalizedHeight));
return(MeasureOutput.Make(
(float)Math.Ceiling(textBlock.DesiredSize.Width),
(float)Math.Ceiling(textBlock.DesiredSize.Height)));
}
private void AddPages(Size containerSize, RichTextBlock layout)
{
if (_flip.Items != null)
{
_flip.Items.Add(new FlipViewItem {
Content = layout
});
layout.Measure(containerSize);
if (layout.HasOverflowContent)
{
var richTextBlockOverflow = new RichTextBlockOverflow();
layout.OverflowContentTarget = richTextBlockOverflow;
_flip.Items.Add(new FlipViewItem()
{
Content = richTextBlockOverflow
});
richTextBlockOverflow.Measure(containerSize);
while (richTextBlockOverflow.HasOverflowContent)
{
var newRichTextBlockOverflow = new RichTextBlockOverflow();
richTextBlockOverflow.OverflowContentTarget = newRichTextBlockOverflow;
richTextBlockOverflow = newRichTextBlockOverflow;
_flip.Items.Add(new FlipViewItem()
{
Content = richTextBlockOverflow
});
richTextBlockOverflow.Measure(containerSize);
}
}
}
}
public RichTextBlock CalculateHeight(RichTextBlock currentTextBlock, double width)
{
var tb = new RichTextBlock {
FontSize = currentTextBlock.FontSize
};
if (_text == null)
{
return(tb);
}
// Create run and set text
Run run = new Run();
run.Text = _text;
// Create paragraph
Paragraph paragraph = new Paragraph();
// Add run to the paragraph
paragraph.Inlines.Add(run);
tb.Blocks.Add(paragraph);
tb.MinWidth = width;
tb.MaxWidth = width;
tb.Width = width;
tb.MaxHeight = Double.PositiveInfinity;
tb.TextWrapping = TextWrapping.WrapWholeWords;
tb.Measure(new Size(width, Double.PositiveInfinity));
tb.Arrange(new Rect(0, 0, width, tb.DesiredSize.Height));
tb.UpdateLayout();
return(tb);
}
public void Changing_Inlines_Should_Reset_Inlines_Parent()
{
using (UnitTestApplication.Start(TestServices.MockPlatformRenderInterface))
{
var target = new RichTextBlock();
var run = new Run("Hello");
target.Inlines.Add(run);
target.Measure(Size.Infinity);
Assert.True(target.IsMeasureValid);
target.Inlines = null;
Assert.Null(run.Parent);
target.Inlines = new InlineCollection {
run
};
Assert.Equal(target, run.Parent);
}
}
public void Changing_InlinesCollection_Should_Invalidate_Measure()
{
using (UnitTestApplication.Start(TestServices.MockPlatformRenderInterface))
{
var target = new RichTextBlock();
target.Measure(Size.Infinity);
Assert.True(target.IsMeasureValid);
target.Inlines.Add(new Run("Hello"));
Assert.False(target.IsMeasureValid);
target.Measure(Size.Infinity);
Assert.True(target.IsMeasureValid);
}
}
public void Changing_Inlines_Properties_Should_Invalidate_Measure()
{
using (UnitTestApplication.Start(TestServices.MockPlatformRenderInterface))
{
var target = new RichTextBlock();
var inline = new Run("Hello");
target.Inlines.Add(inline);
target.Measure(Size.Infinity);
Assert.True(target.IsMeasureValid);
inline.Foreground = Brushes.Green;
Assert.False(target.IsMeasureValid);
}
}
private static MeasureOutput MeasureText(CSSNode node, float width, CSSMeasureMode widthMode, float height, CSSMeasureMode heightMode)
{
// This is not a terribly efficient way of projecting the height of
// the text elements. It requires that we have access to the
// dispatcher in order to do measurement, which, for obvious
// reasons, can cause perceived performance issues as it will block
// the UI thread from handling other work.
//
// TODO: determine another way to measure text elements.
var task = DispatcherHelpers.CallOnDispatcher(() =>
{
var textBlock = new RichTextBlock
{
TextWrapping = TextWrapping.Wrap,
TextAlignment = TextAlignment.DetectFromContent,
TextTrimming = TextTrimming.CharacterEllipsis,
};
var textNode = (ReactTextShadowNode)node;
textNode.UpdateTextBlockCore(textBlock, true);
var block = new Paragraph();
foreach (var child in textNode.Children)
{
block.Inlines.Add(ReactInlineShadowNodeVisitor.Apply(child));
}
textBlock.Blocks.Add(block);
var normalizedWidth = CSSConstants.IsUndefined(width) ? double.PositiveInfinity : width;
var normalizedHeight = CSSConstants.IsUndefined(height) ? double.PositiveInfinity : height;
textBlock.Measure(new Size(normalizedWidth, normalizedHeight));
return(new MeasureOutput(
(float)textBlock.DesiredSize.Width,
(float)textBlock.DesiredSize.Height));
});
return(task.Result);
}
async void OnFlipViewSizeChanged(object sender, SizeChangedEventArgs args)
{
// Get the size of the FlipView
Size containerSize = args.NewSize;
// Actual value gets modified during processing here, so save it
double saveFractionRead = fractionRead;
// First time through after program is launched
if (flipView.Items.Count == 0)
{
// Load book resource
IList <string> bookLines =
await PathIO.ReadLinesAsync("ms-appx:///Books/pg550.txt",
UnicodeEncoding.Utf8);
// Create RichTextBlock
RichTextBlock richTextBlock = new RichTextBlock
{
FontSize = 22,
Foreground = new SolidColorBrush(Colors.Black)
};
// Create paragraphs
Paragraph paragraph = new Paragraph();
paragraph.Margin = new Thickness(12);
richTextBlock.Blocks.Add(paragraph);
foreach (string line in bookLines)
{
// End of paragraph, make new Paragraph
if (line.Length == 0)
{
paragraph = new Paragraph();
paragraph.Margin = new Thickness(12);
richTextBlock.Blocks.Add(paragraph);
}
// Continue the paragraph
else
{
string textLine = line;
char lastChar = line[line.Length - 1];
if (lastChar != ' ')
{
textLine += ' ';
}
if (line[0] == ' ')
{
paragraph.Inlines.Add(new LineBreak());
}
paragraph.Inlines.Add(new Run {
Text = textLine
});
}
}
// Make RichTextBlock the same size as the FlipView
flipView.Items.Add(richTextBlock);
richTextBlock.Measure(containerSize);
// Generate RichTextBlockOverflow elements
if (richTextBlock.HasOverflowContent)
{
// Add the first one
RichTextBlockOverflow richTextBlockOverflow = new RichTextBlockOverflow();
richTextBlock.OverflowContentTarget = richTextBlockOverflow;
flipView.Items.Add(richTextBlockOverflow);
richTextBlockOverflow.Measure(containerSize);
// Add subsequent ones
while (richTextBlockOverflow.HasOverflowContent)
{
RichTextBlockOverflow newRichTextBlockOverflow = new RichTextBlockOverflow();
richTextBlockOverflow.OverflowContentTarget = newRichTextBlockOverflow;
richTextBlockOverflow = newRichTextBlockOverflow;
flipView.Items.Add(richTextBlockOverflow);
richTextBlockOverflow.Measure(containerSize);
}
}
}
// Subsequent SizeChanged events
else
{
// Resize all the items in the FlipView
foreach (object obj in flipView.Items)
{
(obj as FrameworkElement).Measure(containerSize);
}
// Generate new RichTextBlockOverflow elements if needed
while ((flipView.Items[flipView.Items.Count - 1]
as RichTextBlockOverflow).HasOverflowContent)
{
RichTextBlockOverflow richTextBlockOverflow =
flipView.Items[flipView.Items.Count - 1] as RichTextBlockOverflow;
RichTextBlockOverflow newRichTextBlockOverflow = new RichTextBlockOverflow();
richTextBlockOverflow.OverflowContentTarget = newRichTextBlockOverflow;
richTextBlockOverflow = newRichTextBlockOverflow;
flipView.Items.Add(richTextBlockOverflow);
richTextBlockOverflow.Measure(args.NewSize);
}
// Remove superfluous RichTextBlockOverflow elements
while (!(flipView.Items[flipView.Items.Count - 2]
as RichTextBlockOverflow).HasOverflowContent)
{
flipView.Items.RemoveAt(flipView.Items.Count - 1);
}
}
// Initialize the header and Slider
int count = flipView.Items.Count;
pageNumber.Text = "1"; // probably modified soon
pageCount.Text = count.ToString();
pageSlider.Minimum = 1;
pageSlider.Maximum = flipView.Items.Count;
pageSlider.Value = 1; // probably modified soon
// Go to approximate page
fractionRead = saveFractionRead;
flipView.SelectedIndex = (int)Math.Min(count - 1, fractionRead * count);
}
