How to display a little image near a QSlider

[franco.amato]

Hi to all,
I would display a little image at the left of a QSlider. The slider change the volume of a song and instead of put the text Volume: near the slider
I would display a little icon representing the volume so the user can know the meaning of the slider.
I would layout orizontally the icon and the slider so:



m_panPixmap = new QLabel;
QPixmap panPixmap(":/images/pan.png");
panPixmap.scaled(5,5);
m_panPixmap->setPixmap(panPixmap);

m_panSlider = new QSlider(Qt::Horizontal);
m_panSlider->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
m_panSlider->setMinimum( -100 );
m_panSlider->setMaximum( 100 );
m_panSlider->setValue( 0 );

QVBoxLayout panLayout;
panLayout.addWidget(m_panPixmap);
panLayout.addWidget(m_panSlider);


and then add to the main vertical layout

QVBoxLayout* vl = new QVBoxLayout();
vl->setSpacing(20);
vl->addLayout(ll);
vl->addStretch(1);
vl->addLayout(&panLayout); //<-- this is the pan layout
..more code

My problem is that the image is displayed too big and it break the layout. The image and the slider are not displayed correctly.
How can I solve my problem?

Best Regards,
Franco

[franco.amato]

I did a mistake in the previous post.
The real code is:


QHBoxLayout panLayout; //horizontal and not vertical
panLayout.addWidget(m_panPixmap);
panLayout.addWidget(m_panSlider);

but in my program the code is correct.
I don't know how to solve my problem :(

Regards,

[franco.amato]

I changed the code inserting a label instead of an image but the result is still wrong.
I tried to change all without results.
I post some code:


PanelInfo::PanelInfo(QWidget* parent /* = 0 */ )
: QFrame(parent),
m_sound(0)
{
setFrameStyle( QFrame::Box | QFrame::Raised );
setMinimumSize( QSize(150, 240) );
setSizePolicy( QSizePolicy::MinimumExpanding, QSizePolicy::Fixed );

/* labels */
m_durationLabel = new QLabel("DURATION");
m_channelsLabel = new QLabel("CHANNELS");
m_freqLabel = new QLabel("FREQ");
m_bitsLabel = new QLabel("BITS");

m_durationLabel->setMinimumSize( QSize(100, 20) );
m_channelsLabel->setMinimumSize( QSize(100, 20) );
m_freqLabel->setMinimumSize( QSize(100, 20) );
m_bitsLabel->setMinimumSize( QSize(100, 20) );

m_durationLabel->setSizePolicy( QSizePolicy::Preferred, QSizePolicy::Fixed );
m_channelsLabel->setSizePolicy( QSizePolicy::Preferred, QSizePolicy::Fixed );
m_freqLabel->setSizePolicy( QSizePolicy::Preferred, QSizePolicy::Fixed );
m_bitsLabel->setSizePolicy( QSizePolicy::Preferred, QSizePolicy::Fixed );

QVBoxLayout* ll = new QVBoxLayout();
ll->setContentsMargins(0, 0, 0, 0);
ll->setSpacing(0);
ll->addWidget( m_durationLabel );
ll->addWidget( m_channelsLabel );
ll->addWidget( m_freqLabel );
ll->addWidget( m_bitsLabel );

m_panLabel = new QLabel("Pan"); //<----------THIS IS THE PROBLEM

m_panSlider = new QSlider(Qt::Horizontal);
m_panSlider->setMinimumSize(50,20);
m_panSlider->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
m_panSlider->setMinimum( -100 );
m_panSlider->setMaximum( 100 );
m_panSlider->setValue( 0 );

QHBoxLayout panLayout; //<----this layout holds the label and the slider but the result is odd
panLayout.addWidget(m_panLabel);
panLayout.addWidget(m_panSlider);

m_volSlider = new QSlider(Qt::Horizontal);
m_volSlider->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
m_volSlider->setMinimum( 0 );
m_volSlider->setMaximum( 100 );
m_volSlider->setValue( 100 );

/* spinbox */
m_freqControl = new QDoubleSpinBox();
m_freqControl->setMinimum( 0.0 );
m_freqControl->setMaximum( 3.0 );
m_freqControl->setValue( 1.0 );
m_freqControl->setSingleStep( 0.1 );
m_freqControl->setWrapping(1);

QLabel* markerLabel = new QLabel("Markers: ");
QLineEdit *numMarkers = new QLineEdit("0");
numMarkers->setMinimumSize(10,20);
numMarkers->setMaximumWidth(30);
numMarkers->setSizePolicy(QSizePolicy::Minimum, QSizePolicy::Fixed);
numMarkers->setReadOnly(true);
QHBoxLayout* hl = new QHBoxLayout();
hl->setContentsMargins(0, 0, 0, 0);
hl->setSpacing(0);
hl->addWidget( markerLabel );
hl->addWidget( numMarkers );

QVBoxLayout* vl = new QVBoxLayout();
vl->setSpacing(20);
vl->addLayout(ll);
vl->addStretch(1);
vl->addLayout(&panLayout);
vl->addWidget(m_volSlider);
vl->addWidget(m_freqControl);

vl->addLayout(hl);
setLayout(vl);
}

and the result is this 4367.
Where I drawn an arrow you can see that the QSlider is broken and it's painted over the QLabel "pan".
I really don't understand where my code is wrong.
I need help.

Best Regards,
Franco

[Lykurg]

Once again it is a newbie error you do. At the end of your block your layout get distroyed and so both elements are positioned (0,0). Create your layout on the heap (as you do with the other layoute) and all will be fine.

[franco.amato]

Once again it is a newbie error you do. At the end of your block your layout get distroyed and so both elements are positioned (0,0). Create your layout on the heap (as you do with the other layoute) and all will be fine.

Yes it works...thank you
I have a last problem.
I created a horizontal layout with a Label, a slider and again a label so:


QLabel* volLabel = new QLabel("Vol");
m_volValue = new QLabel;
m_volValue->setNum(100);

m_volSlider = new QSlider(Qt::Horizontal);
m_volSlider->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
m_volSlider->setMinimum( 0 );
m_volSlider->setMaximum( 100 );
m_volSlider->setValue( 100 );

QHBoxLayout* volLayout = new QHBoxLayout;
volLayout->setAlignment(Qt::AlignLeft);
volLayout->setSpacing(5);
volLayout->addWidget(volLabel);
volLayout->addWidget(m_volSlider);
volLayout->addWidget(m_volValue);


finally I connect the value of the last Label with the slider:

connect(m_volSlider, SIGNAL( valueChanged(int) ), m_volValue, SLOT(setNum(int) ) );

The problem is that when the value of the volume label change it modify the size of the widget because it's size change too.
How can I fix it?
I set the size policy of the widget containing the layout to fixed without success so:


PanelInfo::PanelInfo(QWidget* parent /* = 0 */ )
: QFrame(parent),
m_sound(0)
{
setFrameStyle( QFrame::Box | QFrame::Raised );
setMinimumSize( QSize(135, 240) );
setSizePolicy( QSizePolicy::Fixed, QSizePolicy::Fixed );
...more code..

I hope to get help as I tried to change all.
Best regards,
Franco

[Lykurg]

use QWidget::setFixedSize().

[franco.amato]

use QWidget::setFixedSize().

Hi the size of the widget change when the value of the label change from 1 to 2 digits ( for example from 9 to 10 ) and from 2 to 3 digits ( for example from 99 to 100 ) and viceversa.
The minimum value is 0 and the maximum is 100.

Regards,
Franco

[Lykurg]

Hi the size of the widget change when the value of the label change from 1 to 2 digits ( for example from 9 to 10 ) and from 2 to 3 digits ( for example from 99 to 100 ) and viceversa.
Yes and therefore use QWidget::setFixedSize() for the label with a proper size that there is enough space for 3 digits. Then the label wont resize ==> the frame/layout neither.

[franco.amato]

Yes and therefore use QWidget::setFixedSize() for the label with a proper size that there is enough space for 3 digits. Then the label wont resize ==> the frame/layout neither.

Thank you very much.
I'll try.

Regards