Qt-从资源添加自定义字体

Question

I added this font to resource: BYekan.ttf
I want to use this font in my application. I've tried this :

    QFont font(":/images/font/BYekan.ttf");
    nLabel->setFont(font);
    nLabel->setText(tr("This is for test"));
    layout->addWidget(nLabel);

But, I guess it's not working. How to use it?

Edit: After reading this question , I've tried again :

int fontID(-1);
bool fontWarningShown(false);
QFile res(":/images/font/Yekan.ttf");
if (res.open(QIODevice::ReadOnly) == false) {
    if (fontWarningShown == false) {
        QMessageBox::warning(0, "Application", (QString)"Impossible d'ouvrir la police " + QChar(0x00AB) + " DejaVu Serif " + QChar(0x00BB) + ".");
        fontWarningShown = true;
    }
}else {
    fontID = QFontDatabase::addApplicationFontFromData(res.readAll());
    if (fontID == -1 && fontWarningShown == false) {
        QMessageBox::warning(0, "Application", (QString)"Impossible d'ouvrir la police " + QChar(0x00AB) + " DejaVu Serif " + QChar(0x00BB) + ".");
        fontWarningShown = true;

    }
    else
        nLabel->setFont(QFont(":/images/font/Yekan.ttf", 10));
}

I compare this font and other font, but there isn't any different on Qt. why?

Answer 1

int id = QFontDatabase::addApplicationFont(":/fonts/monospace.ttf");
QString family = QFontDatabase::applicationFontFamilies(id).at(0);
QFont monospace(family);

Answer 2

在 QML 中，您可以

FontLoader { id: font; source: "/fonts/font.otf" }

Answer 3

I had the same problem as reported in the original question. The above presented solution (answer beginning with the line "int id = QFontDatabase::addApplicationFont....) however did not work, as can be also seen in the comments above. addApplicationFont returned -1.

The reason is, that there is a leading ':' in the string for the call of the function addApplicationFont. I removed this. Now it works for me (testet with Qt 5.5.1 and Qt 4.8.6 on Linux) and returns 0. On Windows it might be necessary to add a drive letter in front.

Note: I had to provide the full path to the font file (eg /usr/share/fonts/ttf/droid/DroidSansFallbackFull.ttf)

Answer 4

No, see, I didn't do any of this. So for me, what I did was there's a ~/.font/ directory, if it doesn't exist you can create it.

Now you copy the ttf into this directory, and Linux will see it. However, in my case, I'm writing a QT application, so these fonts have names, so how does Linux know the name?

If you run the command:

fc-list

It dumps out all the font information systemwide and you can search for the font that you've added.

The output looks something like this:

...
/usr/share/texmf/fonts/opentype/public/lm/lmsans17-oblique.otf: Latin Modern Sans,LM Sans 17:style=17 Oblique,Italic
/home/XXX/.fonts/PAPYRUS.TTF: Papyrus:style=Regular,Normal,obyčejné,Standard,Κανονικά,Normaali,Normál,Normale,Standaard,Normalny,Обычный,Normálne,Navadno,Arrunta
/usr/share/fonts/X11/Type1/n019064l.pfb: Nimbus Sans L:style=Bold Condensed Italic
...

The parts of the output after the first colon on each line is the name of the font as it's seen from inside of Linux for that user. So these are "Latin Modern Sans,LM Sans 17" / "Papyrus" / "Nimbus Sans L". So Linux sees it, and all your applications running as your user will see them also, (Gimp, your Window Manager, QT applications etc etc etc)

Inside your QT application you call the one you are interested in, in my case i'm interested in Papyrus font:

tabWidget->setFont( QFont( "Papyrus",10 ) );

And then, sure enough the QT application just picks up the font...

If you wanted to make the font systemwide, then you'd have to locate the position of the font directories, from what i can see it's /usr/share/fonts/truetype/ you will need to create a subdirectory in there for your fonts but perhaps some other distros may be in a different location, you might want to double check that. Anyhow you can dump the ttf files in there. If you do that, you might want to consider running fc-cache -fv as this will treewalk through the truetype subdirectories seeking out newly added fonts.

With anything font related under Linux, run fc-list . It clears up all sorts of confusions and missunderstandings and sheds light on the otherwise dark and mysterious world of Linux fonts.