Issue with using text wrap for international language

tuanster

I am having an issue with wrapping text within a QML Text element for foreign languages (language that uses Unicode characters like Korean or Chinese). I have the width defined and wrapMode set to Text.WordWrap for my Text element. It works for English language, but when I try to use it for another language, it doesn't work. The text doesn't properly wrap around a blank space as it should.

Any tip is truly appreciated.

Thanks!

mbrasser

Would you be able to paste an example showing this issue?

Thanks,
Michael

tuanster

Sure, here is a simple example to illustrate the issue.

@import QtQuick 1.0

Rectangle {
width: 360
height: 360

Text {
    id: textDisplay
    anchors.centerIn: parent
    textFormat: Text.StyledText
    text: "해리 포터와 죽음의 성물-1부"
    width: 100
    font.wordSpacing: 0
    wrapMode: Text.WordWrap
    horizontalAlignment: Text.AlignLeft
}

}@

Output:

해리 포터와 죽
음의 성물-1부

As you can see, the issue is that on the first line of the output, the line is being wrapped in the middle of the third word.

It works fine for English text or (text with Ascii characters). This issue is observed in language that is non-Ascii.

Please help.

Thanks!

mbrasser

Hi,

Chinese (and as I understand it Korean as well [edit: on further research, this is incorrect for Korean]) are typically written without explicit whitespace between "words" -- this may be why WordWrap allows wrapping at any character boundary. Do you have any experience with other toolkits and how they handle this? (this is Qt-wide behavior, and not specific to QML). Can you give further detail/links on how this mode of wrapping is used for these languages (maybe Qt needs a WrapAtWhitespace option?)?

Regards,
Michael

tuanster

Michael, thanks for the reply. I thought Qt uses whitespace to detect the beginning/ending of a word and that's how it's supposed to work for WordWrap. What do you recommend for solving this issue at the QML level?

I wrote a function in C++ plugin that would take in the font pixel size and the field width and based on that it would break the string into separate lines by adding a QChar::LineSeparator to the original string.

It kind of works but it's not optimal because it doesn't take into account other things such as text font, italics, word space, boldness and other things.

What solution would you recommend?

Thanks much.

mbrasser

Hi,

I'm not sure what to suggest -- from what I understand the WordWrap behavior of Qt/QML is correct for these languages (they rightly break at any character boundary rather than just on explicit whitespace). If you could explain further why you need breaks only on whitespace (or could point to other toolkits/articles/etc regarding this) that would be very helpful.

Regards,
Michael

tuanster

Hi Michael,

Here is the problem that we're having. We have an application that displays the title of a movie in a Text element with width of 100.

Let's take the movie, "Harry Potter And The Deathly." In English, this text is being wrapped correct at the word boundary.

In Korean, the text is "해리 포터와 죽음의 성물-1부" and as you notice, there's a space in between words. When you run the code I posted, you will see that the line breaks at the end of the first character of the third word. It doesn't look good on my application.

If Korean language is treated the same way as English by Qt, I would think it should break into a new line at the end of a word.

Thanks!

mbrasser

Hi,

Okay, thanks for the additional information. I'm not familiar with Korean, and mistakenly thought it was similar to Chinese in the use of whitespace.

Articles like http://msdn.microsoft.com/en-us/goglobal/bb688158.aspx#EEE seem to suggest that breaking between two characters is a more common case for Korean (which is different than English). Experimenting with e.g. TextEdit on OS X and IE on Windows seem to show similar default line-breaking for Korean (usually breaks on character rather than whitespace), while Office seems to break on whitespace by default.

If you can give examples or links showing that wrap-at-whitespace is a common/useful option for Korean (the above link at least suggests that it's an option in some programs), I'd highly suggest raising a bug for it using the "bug tracker":http://bugreports.qt.nokia.com.

Unfortunately I can't think of any great solutions for getting WrapAtWhitespaceOnly-type behavior for Korean from Qt (though you could try experimenting with using the lower-level text APIs in Qt like QTextLayout, etc).

Regards,
Michael

andre

As a work-around, would it be acceptable to use rich text, and put the different words in elements for the time being? That should force wrapping at the spaces.

"해리 포터와 죽음의 성물-1부" would become
@
"<html>해리 포터와 죽음의 성물-1부</html>"
@

For inserting this for single sentences (no line breaks), something like this might work:
@
#include <QStringBuilder>

QString spanify(const QString& input)
{
QStringList elements = input.split(QRegExp("\s"));
QString result = QLatin1String("<html>");
foreach (const QString element, elements) {
result = result % QLatin1String("") % element % QLatin1String(" ");
}
result.chop(1); //remove the last space;
result = result % QLatin1String("</html>");

return result;

}
@

tuanster

Andre,

I just tried your solution and it still doesn't work. I tried putting the "<html>해리 포터와 죽음의 성물-1부</html>" as the text value and changing the text format to rich text, but it's still showing the same output as before. In other words, it doesn't force wrapping at the spaces.

Do you have other ideas for a work-around?

Thanks!

andre

[quote author="tuanster" date="1302192466"]Andre,

I just tried your solution and it still doesn't work. I tried putting the "<html>해리 포터와 죽음의 성물-1부</html>" as the text value and changing the text format to rich text, but it's still showing the same output as before. In other words, it doesn't force wrapping at the spaces.

Do you have other ideas for a work-around?

Thanks!

[/quote]

Sorry, I'm out of ideas. It seemed that that should work, but I guess I was wrong. Sorry to have led you down a blind alley.

goetz

Just a guess: try to replace

@
xxx
// with
xxx
@

tuanster

Thanks for another suggestion.

I just tried it with the "white-space: nowrap" but no luck. It still doesn't work. If I put other attribute like color inside the span tag, the text's color is changed. But the text is still being wrapped in the middle of a word.

QML Text element has a mind of its own.

Any other ideas?

loma27

Hello,

Please try this.

I have used Webview. I have tried this and it seems to be working fine for me.
If this is feasible(changing from Text to Webview) or affordable for your application. This may work for you.

@import QtQuick 1.0
import QtWebKit 1.0

Rectangle {
width: 360
height: 360

WebView{
    html : "<div>해리 포터와 죽음의 성물부</div>"
}

}@

loma27

sorry for wrong code. Please check updated.

@WebView{
html : "<div>해리 포터와 죽음의 성물부</div>"
}
}@

loma27

i have given style width 100px to div but its not coming in comments.

tuanster

Hi Ioma27,

Thanks for your recommendation. It turns out you also have to add the span tag for it to work.

A sample working code is this:

WebView {
    html : "<div><span>해리</span> <span>포터와</span> <span>죽음의</span> <span>성물부</span></div>"
    preferredWidth: 140
    preferredHeight: 400
}

Minkyu Park

Seems there is a patch applied to 5.14
https://code.qt.io/cgit/qt/qtbase.git/commit/?id=d1bab5b1e3d28c0e2925ad3208cea785af755d54