I need to apply Glow effect to QLabel. Text in Black color and glow effect in white(Stroke Effect). I tried in Google but no luck.
If any one knows how apply Glow effect to QLabel then please tell me How to do that.
Yes you can set it on a QLabel:
http://qt-project.org/doc/qt-5/qwidget.html#setGraphicsEffect
You can set a QGraphicsEffect on a widget, as long as you don't mind it not working on a Mac.
label = new QLabel("hello text"));
QGraphicsDropShadowEffect * dse = new QGraphicsDropShadowEffect();
dse->setBlurRadius(10);
label->setGraphicsEffect(dse);
Hope that helps.
I think you're going to be slightly disappointed. To apply an effect, you'll need to use a QGraphicsItem. QLabel isn't. You'll need to use a QGraphicsTextItem inside a QGraphicsScene instead. That probably means you'll need to rebuild your UI if it's already implemented using QWidgets.
Related
I'm new on Qt and I'm looking for some way to modify the form of a QPushButton, but I didn't find something on the web.
Is it possible and if so, how can I do this?
Thx
If you want to change how the QPushButton looks, you can use the Qt style sheets. If you want to put an image on the button, you can take advantage of the "background-image" property of the QPushButton
QPushButton
{
background-image: url("alpha.jpg");
}
You can change other properties like "border", "background-color", etc. Your question needs to be more specific as to what visual elements you need. Go through the documentation, it will help you.
One way to go about getting a different for the QPushButton is to make the necessary image available. Get the necessary image and make sure it has a transparent background. Use could use other attributes of QPushButton like, "background-color: transparent" and without any border - "border: none".
Hope it helps!
In my QGraphicsScene, I would like to set the background brush to the default widget background - but I can't get it.
Kinda like, for my QGraphicsView,
setBackgroundRole(QPalette::Window);
or
setBackgroundBrush(palette().background().color());
(but setting this I see nothing happening)... I also see nothing happening if I set the view color to a bright red).
So I thought I must set color directly on the QGraphicsScene.
For the QGraphicsScene I am trying all sort of combinations like
setBackgroundBrush(QPalette::color(QPalette::Background));
Nothing will even build, seems I require an object (? a widget ?) - but my scene may not have a widget parent... and all I want is a default palette, I thought there would be a generic way to get that color without having a widget ?
On the scene, this will work...
setBackgroundBrush(Qt::red);
No clue why the view won't show color (even if I set on the view, red brush and on the scene transparent).
You may retrieve the QApplication's current style using the static method style(). From there, you may access the QStyle's standard palette using standardPalette(). Use QPalette's brush method to get a brush for a given ColorRole. Putting it all together you get...
QApplication::style()->standardPalette().brush(QPalette::Background)
This may not be the color you are expecting. Check out the documentation on http://doc.qt.io/qt-4.8/qpalette.html, and try different ColorRole values until you find what you're looking for.
Create a temporary widget instance just to access its palette and get the background color:
QColor bgColor = QWidget().palette().background().color();
But I think you should set the background color in the QGraphicsView widget. You can do that by changing its stylesheet. Something like:
QColor bg = ui->graphicsView->palette().background().color();
ui->graphicsView->setStyleSheet(QString("background-color:") + bg.name(QColor::HexArgb));
Setting a transparent background also works.
I'm fairly new to Qt's method of stylesheets and I am looking to adjust the spacing between the icon and text on a QPushButton.
This is the gap I'm referring to: http://imageshack.us/scaled/thumb/593/4kem.png (stackoverflow won't let me post pics yet)
QPushButton {
qproperty-icon: theme_url("/button_action/add");
qproperty-iconSize: 14px;
}
Is there a parameter I can use to adjust this space? I've tried margin, padding, spacing? Perhaps there is a different selector that I can use to just grab the icon?
Actually with QPushButton you are out of luck. You can find a complete list of working options for styling push buttons in the qt documentation ( I am assuming you use qt5, but it is available for other versions as well).
What is often recommended if you want more control over the icon is to exchange your QPushButtons with QToolButtons wich are exactly the same except that they have extra features to make them compatible with toolbars -and- they have more options for icon placement. But this might not work for you because as you can see they are styled the exact same way as QPushButtons. But do look into the "toolButtonStyle" parameter which allows you to move the icon around.
Next on the list comes changing the artwork. If all you want is more space then just add the extra empty pixels to the artwork. This really hurts the perfectionist's mind but is effective.
Next on the list comes subclassing QPushButton and overriding the paint yourself. Sounds more daunting than it is. Subclassing in Qt has become a habit already and it works great. Here is a tutorial i googled in a jiffie (for 4.8 but should be about the same for 5) on the matter of subclassing. It even covers overriding the paint event.
Hope this was helpful.
At least with Qt5.5 (this may change in the future, I hope), besides overriding the paint event, which is complex and in my opinion messy for just a simple thing, there's no inherent Qt way to move that icon a few pixels here or there (small adjustments). If you remove the icon and use a stylesheet to set the background to your icon in your resource URL, you can use background-position property in the stylesheet, but unfortunately it only accepts words like center, left, etc., not pixel adjustments.
Here's how I resolved this problem. I created transparent PNGs that were slightly larger than I needed, where I had like a 4px margin around the icon itself inside the PNG. Then, I just moved the icon inside that canvas and reloaded it into the project resources file, and then mapped it again with the icon property in the designer for the QPushButton, and that worked. I now have icons that line up properly on the left with the text beside it. I can even widen the gap between icon and text.
As of Qt5.7 I don't know of any built-in functionality for the icon/text spacing.
What I usually do is give the image some more space to the right and set the icon size of the button accordingly.
Solution:
Resize your icon file to 32*16 px but leave its content as is.
Call setIconSize(QSize(32, 16)) on your button.
Result: Now there's 16 pixel empty space between its icon and text. 32 pixel is just my example, you can of course set the additional size to something that suites your style.
If you want to apply that on all your button elements simply create a tiny subclass that does it automatically in the constructor. There's really no need to override the paintEvent method for this.
Here is a workaround way to achieve that 'space between text and image':
QPushButton{
border:0px;
image: /*your url*/;
padding-top:16px;
image-position:top;
text-align:bottom;
padding-bottom:10px;
}
since qss doesn't support relative size, you need to implement resize() to change stylesheet when size changing to get a fixed space between text and image.
Here's an opportunistic approach to customize the spacing between text and icon. There's currently no regular way to change the width, so we need to add a transparent area to the right of the icon which is applied to paint device.
Firstly, add a new member variable "m_spacing"(double) and initialize it to 0.0 in constructor, as a factor of expanding the width.
Then, override the "paintEvent", "sizeHint" and "minimumSizeHint".
class CPushButton : public QPushButton {
Q_OBJECT
public:
double spaceRatio() const;
void setSpaceRatio(double ratio);
protected:
double m_spacing;
void paintEvent(QPaintEvent *event) override;
......
QSize CPushButton::sizeHint() const {
QSize sz = QPushButton::sizeHint();
int offset = iconSize().width() * m_spacing;
return QSize(sz.width() + offset, sz.height());
}
QSize CPushButton::minimumSizeHint() const {
QSize sz = QPushButton::minimumSizeHint();
int offset = iconSize().width() * m_spacing;
return QSize(sz.width() + offset, sz.height());
}
void CPushButton::paintEvent(QPaintEvent *event) {
QSize sz = iconSize();
QPixmap tmp = icon().pixmap(sz); // Get the pixmap to apply with right size
sz.rwidth() *= 1 + m_spacing; // Multiply width
QPixmap exp(sz); // Expended
exp.fill(Qt::transparent);
QPainter painter(&exp);
painter.drawPixmap(QRect(QPoint(), tmp.size()), tmp);
QStylePainter p(this); // From Qt source
QStyleOptionButton option; // From Qt source
initStyleOption(&option); // From Qt source
option.icon = QIcon(exp); // Change to real icon
option.iconSize = sz; // Change to real size
p.drawControl(QStyle::CE_PushButton, option); // From Qt source
Q_UNUSED(event)
}
Now you can create a CPushButton instance and set the spacingRatio to 0.1 or other positive real. Visually, it does increase the spacing between text and icon.
The simplest way to go for it is to create your own class inheriting from the QPushButton and override the PaintEvent and then manually place the pixmap of the icon where ever you want.
Best way to solve this problem is adding some blank space in the beginning of QPushButton text. it works well for me!
See here
Is there a way to set a tool tip text for the close button & float button in a QDockWidget ?
As ixSci mentioned, using setTitleBarWidget() is a potential way of solving this problem. Having said that I was looking for a much simpler solution, ideally using QSS (Qt Style Sheets). So after digging into the source code of QDockWidget I found an alternative way which suits my requirement better.
I wanted to find the place these float and close buttons are created. That is inside QDockWidgetPrivate::init() method in QDockWidget.cpp.
As for an example, the float button is created like this:
QAbstractButton *button = new QDockWidgetTitleButton(q);
button->setObjectName(QLatin1String("qt_dockwidget_floatbutton"));
QObject::connect(button, SIGNAL(clicked()), q, SLOT(_q_toggleTopLevel()));
layout->setWidgetForRole(QDockWidgetLayout::FloatButton, button);
Now all I need is to use the flexibility of Qt Style Sheets, for that I need only the Object Name, in this case it's "qt_dockwidget_floatbutton"
So all you need to do, to set tooltips for Close and Float buttons of a QDockWidget, is to add following two lines of styles in your application style sheet
QAbstractButton#qt_dockwidget_closebutton{qproperty-toolTip: "Close";}
QAbstractButton#qt_dockwidget_floatbutton{qproperty-toolTip: "Restore";}
You can implement whatever title widget you want and set it with setTitleBarWidget(). In that widget you can add whatever buttons with tooltips you need.
I want to make something like a hud. I have a QGraphicsScene with a huge QPixmap, that I added to a much smaller QGraphicsView. Now I need to add some control elements, like QLabel, QPushButton and QGraphicsEllipseItem. That's, I think, is not a problem. I found this helpful page Graphics View Classes. But how do I anchor this control elements to the View or maybe better said how do I not anchor them? When I drag the QPixmap, then I don't want that the hud is moving with the QPixmap out of the QGraphicsView.
What do I need to do, to solve this problem. Hope someone can help me.
You should just have to create your widgets and specify the QGraphicsView in the constructor like this:
QPushButton *button1 = new QPushButton(view);