How can I modify an existing stylesheet?
For example: if I want to create buttons, which when pressed each modify a single aspect of the stylesheet. One button can insert a margin-left attribute of 10. Another button can make the background colors blue. Lastly, another button can round the corners. The trick here though, is that I dont want to store all the variables and rebuild the style sheet on each button press. I would like to have a simple this->setStyleSheet(this->getStylesheet()+"margin-left: 10px:") for example.
Is there any way to do this?
Here is the code in main.cpp
QWidget wdg;
QHBoxLayout hlay;
wdg.setStyleSheet("border:2px solid rgb(74, 74, 74);");
QPushButton btn;
btn.setStyleSheet("border-radius:5px;");
btn.setText("Hello");
QPushButton btn2;
btn2.setStyleSheet("background-color: rgb(190, 190, 190);");
btn2.setText("Hello");
hlay.addWidget(&btn);
hlay.addWidget(&btn2);
qDebug()<<btn.styleSheet();
wdg.setLayout(&hlay);
wdg.show();
setting and getting style sheet works with QString and so you can use + operator.
Related
I have a QWidget which should take place over the central widget of my application which is a VideoWidget for playing video. The problem is that I can't set background of the QWidget to be transparent.
Use a StyleSheet (you can do that in code with setStylesheet or in the ui file : RMB on the widget you want "Change stylesheet" or even in the properties tab)
for instance
"background-color: rgba(255, 255, 0, 50);"
gives a yellow transparant look:(example of a button used on top of another button)
With stylesheets you can control the look of a complete program or just the specific widgets you want. More info in the style sheet reference
You could make the full Widget invisible:
QWidget::setHidden(true);
I'm new to Qt and the difference between QPushButton and QToolButton is not so clear to me.
I know that a QToolButton is usually used in a QToolBar and it usually shows only an icon, without text, but I don't quite understand the main difference between both.
Does it have any bigger difference?
When should I use QPushButton and when should I use QToolButton?
I would like to know this to use the most appropriate button, and I need to perform some GUI tests and maybe it can be relevant.
QPushButton is simply a button. QToolButton is part of a group of widgets in the QtWidgets module that operate on QActions: QMenu and QToolBar are other examples. As a result, QToolButton is much more complex under the hood than QPushButton.
Some examples of how they are different in practice:
QToolButton is tightly integrated with QAction. Changing the icon, text, or other properties of a tool button's default action is reflected on the button.
You can change the layout of the tool button contents (icon only, text only, text beside icon, text below icon). This is not possible for a QPushButton.
QToolButton supports a "split" button type: a sidebar hot zone opens a menu instead of triggering the default action.
Tool buttons can be created directly in a QToolBar by adding an action. Other widgets must be explicitly added to the toolbar.
A tool button is meant to be displayed in a grid, so it has smaller default internal margins than a push button.
QPushButton is more for "Ok"/"Close" type buttons that contain text with an optional icon.
A QToolButton should generally have an icon.
A QPushButton should always have text.
From Qt doc: http://doc.qt.io/qt-5/qtoolbutton.html#details
"A tool button is a special button that provides quick-access to specific commands or options. As opposed to a normal command button, a tool button usually doesn't show a text label, but shows an icon instead."
When i want a button in the GUI simple with only an icon, I use QToolButton. But when i want a classic button, i use QPushButton.
No big differences,
I want to change the styleSheet of my QmenuBar window. for QPushButton or any thing like this, there are several example like the following links {this} and {this}. But I couldn't find any example for QmenuBar.
and I want to change the color of window background.
(I attach an image)
I am creating a program that draws graphs; I want to be able to have a button that a user can press to choose the line color and style. I want to be able to visually show what the current selection is.
Currently, I know that I can do that using two seperate widgets, a QPush button, and then a widget I make myself that just draws a line across it using QPen.
I would like to turn these two widgets into a single widget. I want this widget to be a pushable "button" that the user presses and I can get a signal out of to run a routine that sets a new QPen.
Is this functionality built in? Or would I need to create a new widget that re-implements either QPushButton or QActionButton? Or should I just make my widget which listens to mouseclick events on it and create a signal slot from there?
You could use a QLabel, set the style sheet, and use that as your line on the graph. You could use the bounds of a QGroupBox to define x and y axis.
Maybe something like this:
yourQLabel.setStyleSheet("QWidget {background-color: rgb(255, 0, 0); color:white; border: 1px solid black;}"); // red with black border
Then you can set the height, width and position of the QLabel based on values for your graph. Of course this will only work if lines on your graphs are rectangular. If they aren't, then you'll probably have to use something other than QLabel.
Use the setGeometry method of QLabel to set this.
yourQLabel.setGeometry(x, y, width, height);
As far as your button, you can do something similar with that if you want. A QPushButton also has the setGeometry and setStyleSheet methods.
If you want to tell your button to do something on click, assuming you have a QPushButton object called myButton, add this to your header file (.h):
class YourClass
{
Q_OBJECT
//...
private slots:
void on_myButton_clicked();
}
Then in your source file (.cpp):
void YourClass::on_myButton_clicked()
{
// stuff your button does on click
}
I have a QLabel in my application that displays error messages to the user. I would like to make the text of the label selectable so users can copy and paste the error message if needed.
However, when I use the mouse to click and drag over the text, nothing happens - the text is not selected.
How can I make the text within a QLabel selectable by the mouse?
Code
The text of a QLabel can be made selectable by mouse like so:
label->setTextInteractionFlags(Qt::TextSelectableByMouse);
This is found in the QLabel documentation.
You can use that same function to make links selectable by keyboard, highlight URL links, and make the text editable. See Qt::TextInteractionFlag.
Designer
Search for textInteractionFlags under the QLabel menu and set the flag TextSelectableByMouse.
Here is another method, for reference...
You could create a QLineEdit subclass instead, tweaked to look and act like a QLabel,
in the constructor:
setReadOnly(true);
setFrame(false);
QPalette palette = this->palette();
palette.setColor(QPalette::Base, palette.color(QPalette::Background));
setPalette(palette);
I think the accepted answer is simpler and preferable to this though.