How to judge text block is trimming with ...

Question

I have set text block TextTrimming property to WordEllipsis. And i only want to show tooltip when the text block does not show the whole text.
Currently, i used the following mehtod,  but the precision is not too good.

FormattedText fText = new FormattedText(txtBlock.Text, System.Globalization.CultureInfo.CurrentUICulture, FlowDirection.LeftToRight,

new Typeface(txtBlock.FontFamily, txtBlock.FontStyle, txtBlock.FontWeight, txtBlock.FontStretch), txtBlock.FontSize, Brushes.Black);

Rect desiredRect = fText.BuildGeometry(new Point(0, 0)).Bounds;

double desiredWidth = desiredRect.Width + (txtBlock.ActualHeight - desiredRect.Height) - 1;

if (desiredWidth > txtBlock.ActualWidth)

{

//...

}

 

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anders06

Answer 1

Any suggestion?

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anders06

Answer 2

I think you could use the following extension method to determine if a specified TextBlock has been trimmed without calling BuildGeometry() to get the size of the underlying geomtrical metrics which could be different from my personal experience:

public static class TextBlockExtensions
{
    public static Boolean IsTextTrimmed(this TextBlock textBlock)
    {
        Typeface typeface = new Typeface(textBlock.FontFamily,
            textBlock.FontStyle,
            textBlock.FontWeight,
            textBlock.FontStretch);

        // FormattedText is used to measure the whole width of the text held up by TextBlock container.
        FormattedText formmatedText = new FormattedText(
            textBlock.Text,
            System.Threading.Thread.CurrentThread.CurrentCulture,
            textBlock.FlowDirection,
           typeface,
            textBlock.FontSize,
            textBlock.Foreground);

        return formmatedText.Width > textBlock.Width;
    }
}

Answer 3

Thanks, Marco.
It works so perfect.

And it should be "return  formmatedText.Width > textBlock.ActualWidth;“  :) 

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anders06