Is it possible to use Elide with QLabel?

Question

Is it possible to use Elide with QLabel?

Navigation

#1 by (6 votes)
#2 by (2 votes)

3

I want to use the element QLabel and if the text execest the width size it may look like this:

Add 3 points to the right:
```
Foo bar baz foo bar...
```
Add 3 points from the center:
```
Foo bar ba...oo bar baz
```
Add 3 points left:
```
...bar baz foo bar baz
```

Is it possible to do this natively, or do I have to reimplement using QFontMetrics with QResizeEvent ?

qt

asked by anonymous 21.12.2016 / 13:06

2 answers

6

There does not seem to be anything native. But you can use the QFontMetrics::elidedText method to implement an elided text of a line. Here's an example ( original source of the SOen sample ):

QString text("some long text without elipsis");
QFontMetrics metrics(label->font());
QString elidedText = metrics.elidedText(text, Qt::ElideRight, label->width());
label->setText(elidedText);

There is also a more complete example in the Qt documentation, where a new class specific to this is implemented to allow doing this in Labels with multiple lines. Oh, you can also use the%% Qxt extension class because it already implements what you you want the method QxtLabel .

21.12.2016 / 13:27

Randomly position div when loading page Character manipulation in PHP

score 2 · Accepted Answer

The response from Luiz helped me, however I needed something I did automatically, I thought I'd use paintEvent or something, but resizeEvent worked fine,

elidedlabel.h

#ifndef ELIDEDLABEL_H
#define ELIDEDLABEL_H

#include <QLabel>

class ElidedLabel : public QLabel
{
    Q_OBJECT

public:
    explicit ElidedLabel(QWidget *parent=0, Qt::WindowFlags f=0);
    explicit ElidedLabel(const QString &text, QWidget *parent=0, Qt::WindowFlags f=0);
    void setType(const Qt::TextElideMode type);

public slots:
    void setText(const QString &text);
    void elide();

protected:
    void resizeEvent(QResizeEvent *event);

private:
    QString original;
    Qt::TextElideMode defaultType;
    bool eliding;

};

#endif // ELIDEDLABEL_H

elidedlabel.cpp

#include "elidedlabel.h"

#include <QResizeEvent>
#include <QTimer>

ElidedLabel::ElidedLabel(QWidget *parent, Qt::WindowFlags f) :
    QLabel(parent, f)
{
    defaultType = Qt::ElideMiddle;
    eliding = false;
    original = "";
}

ElidedLabel::ElidedLabel(const QString &text, QWidget *parent, Qt::WindowFlags f) :
    QLabel(text, parent, f)
{
    defaultType = Qt::ElideMiddle;

    //Usado para verificar se a string está ou não sendo atualizado
    eliding = false;

    //Guarda o texto original
    setText(text);
}

void ElidedLabel::setType(const Qt::TextElideMode type)
{
    /*
       Altera o tipo de elide, podendo ser:
       Esquerda: "... bar baz"
       Meido: "Foo ... baz"
       Direita: "Foo bar ..."
    */
    defaultType = type;
    elide();
}

//Atualiza o texto se o Label for redimensionado
void ElidedLabel::resizeEvent(QResizeEvent *event)
{
    Q_UNUSED(event);

    //O delay é necessário para evitar conflitos
    QTimer::singleShot(50, this, SLOT(elide()));
}

//Atualiza o texto
void ElidedLabel::setText(const QString &text)
{
    original = text;
    QLabel::setText(text);

    //Executa no momento que é atualizado
    elide();
}

void ElidedLabel::elide()
{
    if (eliding == false) {
        eliding = true;

        QFontMetrics metrics(font());
        QLabel::setText(metrics.elidedText(original, defaultType, width()));

        eliding = false;
    }
}

To use just call it like this:

#include "elidedlabel.h";

...

ElidedLabel label1;

Or:

ElidedLabel *label1 = new ElidedLabel;