Question

I am facing problem while Setting text in QPushbuuton.
I set the text on a button , but it never appears.

I have written a Custom Class for mousepress,mouserelease event for QPushbutton.

I Promote my QPushbutton to this class.

My code looks like :

//Customclass.h

enum ButtonState
{
Normal,
MouseOver,
Pushed
};

class CustomButtonStates : public QPushButton
{
    Q_OBJECT


public:
    explicit CustomButtonStates(QWidget *parent = 0,const QString &normal = "", const QString &active = "",QString strText = "");
    virtual ~CustomButtonStates();
    void mousePressEvent(QMouseEvent  *event);
    void mouseReleaseEvent(QMouseEvent  *event);
    void paintEvent(QPaintEvent *e);



private:

    QString m_PixmapNormal;
    QString m_PixmapActive;
    QString m_strText;
    bool m_bPressed;
    ButtonState state;

public:
    QImage *NormalImage;
    QImage *MouseOverImage;
    QImage *PushedImage;




};

// .cpp

CustomButtonStates::CustomButtonStates(QWidget *parent,const QString &normal, const QString &active,QString strText) :
    QPushButton(parent)
{

    m_PixmapNormal = normal ;
    m_PixmapActive = active ;
    m_strText = strText ;
    state = Normal;



}


void CustomButtonStates::mousePressEvent(QMouseEvent *event)
{
    QPushButton::mousePressEvent(event);
    state = Pushed;    
    this->repaint();

}

void CustomButtonStates::mouseReleaseEvent(QMouseEvent *event)
{
    QPushButton::mouseReleaseEvent(event);
    state = Normal;
    emit clicked();
    this->repaint();

}

void CustomButtonStates::paintEvent(QPaintEvent *event)
{
    QPainter painter(this);
    QImage *pic = NULL;

    NormalImage = new QImage(m_PixmapNormal);
    PushedImage = new QImage(m_PixmapActive);
    switch (state)
    {
    case Normal:
        pic = NormalImage;
        break;
    case MouseOver:
        pic = MouseOverImage;
        break;
    case Pushed:
        pic = PushedImage;
        break;
    default:
        pic = NormalImage;
        break;
    }

    painter.drawImage(0, 0, *pic);
}

CustomButtonStates::~CustomButtonStates()
{
    delete NormalImage;
    delete MouseOverImage;
    delete PushedImage;
}

In my Page :

 CustomButtonStates *btnMain ;
btnMain = new CustomButtonStates(this,":/Sampl1.png",":/Sample2.png","Users");
    btnMain->setText("Users");
    btnMain->setGeometry(QRect(3,6,65,33));

    connect(btnMain,SIGNAL(clicked()),this,SLOT(on_btnUsers_clicked()));

Answer 1

If you don’t need any of the stuff painted in the QPushButton except the text and your data (images/pixmaps), I suggest you can go a little deeper an directly inherits of QAbstractButton instead.

In your button you will add a text member (plus accesors setText(const QString&...) and text()) then re-implement the paint event to draw your image and at last text above this background with one of the drawText() method of the QPainter.

paintEvent will look like this :

void YourButton::paintEvent(QPaintEvent* event)
{
    QPainter painter(this);
    //hereadd some logic to determine witch pixmap goes background
    QPixmap* selectedPixmap ...
    painter.drawPixmap( rect(), *selectedPixmap);
    //here add some logic to set painter pen and brush 
    //according to button status (enabled/checked/...)
    painter.drawText( rect(), Qt::AlignCenter, text());
}

If you need fancier stuff like word wrapping, or Qt ‘css’ style to be applied to you text I suggest to use directly a QLabel and forward text accessor to this QLabel. In this case do not forget to re-implement resizeEvent to set correctly the overlay label on the top of your button rectangle any time it is changing.