I would like to show the status of icons in toolbar (whether they are activated). For example, When I click Bold, Italic or Underline icon in Microsoft word, it will be shaded, and switch to normal status when I click it again.
It's not necessary to be shaded. I just need to distinguish whether it is activated.
You have to checkable the QAction, or use a QWidget that is checkable like QToolButton:
#include <QtWidgets>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QMainWindow w;
QToolBar *toolbar = w.addToolBar("Toolbar");
QAction *bold_action = toolbar->addAction("B");
QFont bold_fn(bold_action->font());
bold_fn.setBold(true);
bold_action->setFont(bold_fn);
bold_action->setCheckable(true);
QAction *italic_action = toolbar->addAction("I");
QFont fn_cursive(italic_action->font());
fn_cursive.setItalic(true);
italic_action->setFont(fn_cursive);
italic_action->setCheckable(true);
QAction *underline_action = toolbar->addAction("U");
QFont fn_underline(underline_action->font());
fn_underline.setUnderline(true);
underline_action->setFont(fn_underline);
underline_action->setCheckable(true);
QAction* subscript_action = new QAction;
subscript_action->setIcon(QIcon(":/subscript.png"));
subscript_action->setCheckable(true); // <---
toolbar->addAction(subscript_action);
w.setCentralWidget(new QTextEdit);
w.resize(320, 240);
w.show();
return a.exec();
}
Output:
Related
I have QSplitter set as the central widget:
MainWindow::MainWindow(QWidget *parent)
: QMainWindow(parent),
mdiArea(new QMdiArea)
{
QWidget *widget = new QWidget;
widget->setMinimumSize(100, 100);
QSplitter *splitter = new QSplitter;
splitter->addWidget(mdiArea);
splitter->addWidget(widget);
setCentralWidget(splitter);
createActions();
}
void MainWindow::createSubwin()
{
QWidget *subwin = new QWidget(mdiArea);
subwin->setWindowTitle("Subwindow");
subwin->setMinimumSize(100, 100);
mdiArea->addSubWindow(subwin);
subwin->show();
}
void MainWindow::createActions()
{
QAction *actSub = new QAction("Add subwindow", this);
connect(actSub, SIGNAL(triggered()), SLOT(createSubwin()));
QMenu *winMenu = menuBar()->addMenu("Windows");
winMenu->addAction(actSub);
}
When I press maximize button of subwindow, the subwindow covers entire main window. Is there any way to prevent such behaviour and make subwindow occupy all the space of QMdiArea instead?
UPD: It looks like that the problem occurs only when at least one menu in main window's QMenuBar is present. Without menuBar everything works as expected:
https://www.qtcentre.org/threads/44457-QMdiSubWindow-maximizing-problem
Regarding the QSplitter, I gave OP the following hint:
Move the right part of the QSplitter into a dock widget (and drop the QSplitter), so that the left part is the only part of the QMainWindow::centralWidget(). This would mean to work with the existing class instead of against, and is probably easier to manage.
OP appreciated the hint with the dock widget but claimed the sub-window will still occupy the whole main window.
I must admit my lack of experience with MDI and made an MCVE to prove me myself right or wrong:
#include <QtWidgets>
// main application
int main(int argc, char **argv)
{
qDebug() << "Qt Version:" << QT_VERSION_STR;
QApplication app(argc, argv);
// setup GUI
QMainWindow qWinMain;
qWinMain.setWindowTitle("QMainWindow - MDI - Dock");
qWinMain.resize(640, 480);
// MDI
QMdiArea qMDI;
qWinMain.setCentralWidget(&qMDI);
// MDI sub widget
QLabel qWinSub("MDI Sub-Window\nwidget");
qMDI.addSubWindow(&qWinSub);
// Dock
QDockWidget qDock;
qDock.setWindowTitle("Dock");
QLabel qLblDock("Dock\nwidget");
qDock.setWidget(&qLblDock);
qWinMain.addDockWidget(Qt::RightDockWidgetArea, &qDock);
qWinMain.show();
// runtime loop
return app.exec();
}
Output:
So, I cannot reproduce OPs claim—it works on my side.
My platform: Windows 10, VS2019, Qt5.15
I enhanced the first MCVE a bit to see how it works if MDI sub-windows are created after qWinMain.show() (what's expected as the usual case).
#include <QtWidgets>
// main application
int main(int argc, char **argv)
{
qDebug() << "Qt Version:" << QT_VERSION_STR;
QApplication app(argc, argv);
// setup GUI
QMainWindow qWinMain;
qWinMain.setWindowTitle("QMainWindow - MDI - Dock");
qWinMain.resize(640, 480);
// MDI
QMdiArea qMDI;
qWinMain.setCentralWidget(&qMDI);
// Dock
QDockWidget qWinDock;
qWinDock.setWindowTitle("Dock");
QWidget qDock;
QVBoxLayout qVBoxDock;
QPushButton qBtnNewMDISubWin("New Sub-Window");
qVBoxDock.addWidget(&qBtnNewMDISubWin);
qDock.setLayout(&qVBoxDock);
qWinDock.setWidget(&qDock);
qWinMain.addDockWidget(Qt::RightDockWidgetArea, &qWinDock);
// create sub-window
int i = 0;
auto createSubWin = [&]() {
++i;
QLabel* pQWinSub = new QLabel(QString("MDI Sub-Window\nwidget %1").arg(i));
pQWinSub->setWindowTitle(QString("MDI Sub-Window %1").arg(i));
qMDI.addSubWindow(pQWinSub);
pQWinSub->show();
};
// install signal handlers
QObject::connect(&qBtnNewMDISubWin, &QPushButton::clicked,
createSubWin);
// runtime loop
qWinMain.show();
return app.exec();
}
Output:
It still works on my side as expected.
Note:
I had to add the explicit pQWinSub->show(); after qMDI.addSubWindow(pQWinSub); (which was not necessary in the first MCVE). However, this is exactly how it's done by OP's code.
OPs reply:
It turns out that the problem occurs only when menuBar is present
Oha. How comes?
I extended my MCVE again to add a menu bar:
#include <QtWidgets>
// main application
int main(int argc, char **argv)
{
qDebug() << "Qt Version:" << QT_VERSION_STR;
QApplication app(argc, argv);
// setup GUI
QMainWindow qWinMain;
qWinMain.setWindowTitle("QMainWindow - MDI - Dock");
qWinMain.resize(640, 480);
// menu
QMenuBar qMenuMain;
QAction qCmdFile("File");
QMenu qMenuFile;
QAction qCmdFileNew("New");
qMenuFile.addAction(&qCmdFileNew);
qCmdFile.setMenu(&qMenuFile);
qMenuMain.addAction(&qCmdFile);
qWinMain.setMenuBar(&qMenuMain);
// MDI
QMdiArea qMDI;
qWinMain.setCentralWidget(&qMDI);
// Dock
QDockWidget qWinDock;
qWinDock.setWindowTitle("Dock");
QWidget qDock;
QVBoxLayout qVBoxDock;
QPushButton qBtnNewMDISubWin("New Sub-Window");
qVBoxDock.addWidget(&qBtnNewMDISubWin);
qDock.setLayout(&qVBoxDock);
qWinDock.setWidget(&qDock);
qWinMain.addDockWidget(Qt::RightDockWidgetArea, &qWinDock);
// create sub-window
int i = 0;
auto createSubWin = [&]() {
++i;
QLabel* pQWinSub = new QLabel(QString("MDI Sub-Window\nwidget %1").arg(i));
pQWinSub->setWindowTitle(QString("MDI Sub-Window %1").arg(i));
pQWinSub->setFrameShape(QFrame::Box);
qMDI.addSubWindow(pQWinSub);
pQWinSub->show();
};
// install signal handlers
QObject::connect(&qCmdFileNew, &QAction::triggered,
createSubWin);
QObject::connect(&qBtnNewMDISubWin, &QPushButton::clicked,
createSubWin);
// runtime loop
qWinMain.show();
return app.exec();
}
Output:
Note:
I partly agree with OP:
Yes, the look of the maximized MDI is a bit different now. It looks like it occupies the whole client area of the main window but…
…the dock widget is still visible. I added a box to the QLabel (the top widget in the MDI sub-window) to illustrate this. In fact, the sub-window still occupies the central widget only (regardless what the look of its title bar suggests).
I want to create custom Layout alike here: http://doc.qt.io/qt-5/qtwidgets-layouts-flowlayout-flowlayout-cpp.html
I want some methood to put checkbox on top of custom button. For now there are
setGeometry(QRect(QPoint(...
methods for either button and checkbox but whether I'm doing it for button or checkobox first still checkbox appears "under" the button and I can't see/click it.
How can I put checkbox on top of button there?
Simply make the checkbox a child of the button and call setGeometry relative to the button. Children are always drawn on top of their parents.
QPushButton button("Hello World!", &w);
button.setGeometry(0,0,100,100);
button.show();
QCheckBox checkBox(&button);
checkBox.setGeometry(button.rect());
checkBox.show();
No need to put the checkbox into a layout.
I have just made this snippet to check the checkbox on the top of the button and it works for me.
#include "mainwindow.h"
#include <QApplication>
#include <QPushButton>
#include <QCheckBox>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QWidget w;
QPushButton button("Hello World!", &w);
button.setGeometry(0,0,100,100);
button.show();
QCheckBox checkBox(&w);
checkBox.setGeometry(30,30,50,50);
checkBox.show();
w.show();
return a.exec();
}
and here is if you will change the order of "parenting" and want checkbox still be on the top:
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QWidget w;
QCheckBox checkBox(&w);
checkBox.setGeometry(30,30,50,50);
checkBox.show();
QPushButton button("Hello World!", &w);
button.setGeometry(0,0,100,100);
button.show();
checkBox.setParent(NULL);
checkBox.setParent(&w);
w.show();
return a.exec();
}
What I want to do with this piece of code is set the focus on the QMenu Item programmatically. But neither QMenu::setActiveAction() nor QMenu::popup() works.
How can I do that?
#include <QApplication>
#include <QMainWindow>
#include <QMenuBar>
int main(int argc, char **argv)
{
QApplication app(argc, argv);
QMainWindow *window = new QMainWindow();
window->setWindowTitle(QString::fromUtf8("Test:QMenu"));
window->resize(336, 227);
QAction *newAct = new QAction("&New",window);
QAction *openAct = new QAction("&Open",window);
QAction *saveAct = new QAction("&Save",window);
QMenu *fileMenu;
fileMenu = window->menuBar()->addMenu("&File");
fileMenu->addAction(newAct);
fileMenu->addAction(openAct);
fileMenu->addAction(saveAct);
window->show();
fileMenu->popup(QPoint(10,10));
return app.exec();
}
QMenu items are not "focusable" in the same manner as other widgets. And, actually, they shouldn't, because what you want is not common practice of their usage.
As a workaround, on mouse press you can get mouse cursor position, pre-calculate offset of your default menu item in the popup menu and show the menu at the point, where mouse cursor underly your default menu item. This solution was suggested here.
Also, what will be more nice for user, to select default menu item you can generates narrow keys buttons events after you display your popup. This works on Windows, but not sure about other OS.
I am trying to add a label to the main window using Qt. Here is a piece of the code:
int main(int argc, char *argv[]) {
QApplication app(argc, argv);
QWidget Main_Window;
QPixmap Image;
Image.load("1837.jpg");
QLabel i_label;
i_label.setPixmap(Image);
i_label.show();
QPushButton Bu_Quit("Quit", &Main_Window);
QObject::connect(&Bu_Quit, SIGNAL(clicked()), qApp, SLOT(quit()));
Main_Window.show();
return app.exec();
}
I've been having a very hard time figuring out how to properly add QLabels to QWidgets, I tried to set the Main_Window as the main widget using this method: app.setMainWidget(Main_Window) and the label was still outside the window. So how do I put labels into widgets using Qt?
hamza, this code worked fine for me:
#include <QtGui>
int main(int argc, char *argv[])
{
QApplication app(argc, argv);
QWidget Main_Window;
QLabel i_label("Start", &Main_Window);
//i_label.setPixmap(QPixmap("1837.jpg"));
QPushButton Bu_Quit("Quit" , &Main_Window);
QObject::connect(&Bu_Quit , SIGNAL(clicked()), qApp , SLOT(quit()));
QVBoxLayout *vbl = new QVBoxLayout(&Main_Window);
vbl->addWidget(&i_label);
vbl->addWidget(&Bu_Quit);
Main_Window.show();
return app.exec();
}
I commented setting the image code to show you that the label was set correctly. Make sure your image is valid (otherwise you won't see the text). The trick here was that you need to use qt layouts like QVBoxLayout
Add the label to a layout widget and set the window layout to that layout.
Design note: its better to create your own MainWindow class, inheriting from QMainWindow for instance, and design it from the inside.
or even better, use QtCreator.
You can try:
QWidget window;
QImage image("yourImage.png");
QImage newImage = image.scaled(150, 150, Qt::KeepAspectRatio);
QLabel label("label", &window);
label.setGeometry(100, 100, 100, 100);
label.setPixmap(QPixmap::fromImage(newImage));
window.show();
this way you can even decide where to put the label and choose the image size.
Basically, I want a simple pushButton with a colorful text which when pressed exits the application.
Why cant I press PushButton in this simple program. I am using QT 4.6 on Arch x86_64.
#include <QtGui/QApplication>
#include <QLabel>
#include <QPushButton>
#include<QtGui>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QMainWindow *Main=new QMainWindow;
QPushButton *button = new QPushButton(Main);
QLabel *label = new QLabel(Main);
label->setText("<h2><i>Hello</i> ""<font color=red>Qt!</font></h2>");
label->setVisible(true);
QObject::connect(button, SIGNAL(clicked()),label, SLOT(close()));
label->setAlignment(Qt::AlignCenter|Qt::AlignVCenter);
label->setWindowTitle("HelloWorld Test Program");
Main->show();
return a.exec();
}
Beside the use of a button class that will allow you to display rich text, you also need to make sure your connections are correct.
In your example, you're connecting the clicked signal of the button to the clear() slot of the label, which is non-sense.
To exit your app when the button is clicked, you need to close the main window. Here is the code to get the right connection :
QObject::connect(button, SIGNAL(clicked()),Main, SLOT(close()));
Changing this single line of code in your example is not enough, because your label is drawn on top of your button, so it's not possible to graphically click on it. You need to hide your label and put some text into your button :
button->setText("Hello");
label->setVisible(false);
Regarding the rich text feature in a QPushButton, AFAIK it is not possible to do it with a QPushButton.
UPDATE :
Here is a way to put some richtext on a QPushButton. It uses the solution described by my comment : painting a QTextDocument onto a pixmap and setting this pixmap as the button's icon.
#include <QtGui/QApplication>
#include <QLabel>
#include <QPushButton>
#include <QtGui>
#include <QTextDocument>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QMainWindow *Main=new QMainWindow;
QPushButton *button = new QPushButton(Main);
QTextDocument Text;
Text.setHtml("<h2><i>Hello</i> ""<font color=red>Qt!</font></h2>");
QPixmap pixmap(Text.size().width(), Text.size().height());
pixmap.fill( Qt::transparent );
QPainter painter( &pixmap );
Text.drawContents(&painter, pixmap.rect());
QIcon ButtonIcon(pixmap);
button->setIcon(ButtonIcon);
button->setIconSize(pixmap.rect().size());
QObject::connect(button, SIGNAL(clicked()),Main, SLOT(close()));
Main->show();
return a.exec();
}
Take a look here. Widget called QwwRichTextButton.
The QwwRichTextButton widget provides a button that can display rich text.