In qdialog i put some input that i need in the mainwindow, how can i get them? my program is something like this, I have a qdialog that must open before mainwindow, I put there some input and click ok, and then the mainwinodw opens using those inputs.
here's the dialog.cpp code:
#include "dialog.h"
#include "ui_dialog.h"
#include "vtkBMPReader.h"
// Define the length of the volume
void Dialog::bmprange()
{
// Getting some proprieties for the lenght of the volume
QString XMAX=ui->lineEdit->text();
double xMax=XMAX.toDouble();
QString YMAX=ui->lineEdit_2->text();
double yMax=YMAX.toDouble();
QString ZMAX=ui->lineEdit_3->text();
double zMax=ZMAX.toDouble();
QString XMMAX=ui->lineEdit_4->text();
double xMMax=XMMAX.toDouble();
QString YMMAX=ui->lineEdit_5->text();
double yMMax=YMMAX.toDouble();
QString ZMMAX=ui->lineEdit_6->text();
double zMMax=ZMMAX.toDouble();
if (xMax==0 || yMax==0 || zMax==0 || xMMax==0 || yMMax==0 || zMMax==0)
{
ui->label_17->setText("Error: invalid measures");
}
else
{
// Using vtkBMPReader to read all the 128 bmp slices
vtkBMPReader *bmp= vtkBMPReader::New();
bmp->SetDataByteOrderToLittleEndian();
bmp->SetFilePrefix ("/home/matt/Desktop/ouBMP/exemplo");
bmp->SetFilePattern("%s%d.bmp");
bmp->SetFileNameSliceSpacing(1);
bmp->SetNumberOfScalarComponents(3);
bmp->SetDataOrigin(0,0,0);
bmp->SetDataSpacing(xMMax/(xMax-1.0),xMMax/(yMax-1.0),xMMax/(zMax-1.0));
bmp->SetDataExtent(0,xMax-1.0,0,yMax-1.0,1,zMax);
bmp->Update();
ui->label_17->setText("Valid measures");
}
}
Dialog::Dialog(QWidget *parent) :
QDialog(parent),
ui(new Ui::Dialog)
{
ui->setupUi(this);
// Control volume measures
// Making the lineedit objects only accept numbers
ui->lineEdit->setValidator(new QIntValidator(this));
ui->lineEdit_2->setValidator(new QIntValidator(this));
ui->lineEdit_3->setValidator(new QIntValidator(this));
ui->lineEdit_4->setValidator(new QDoubleValidator(this));
ui->lineEdit_5->setValidator(new QDoubleValidator(this));
ui->lineEdit_6->setValidator(new QDoubleValidator(this));
connect(ui->lineEdit, SIGNAL(textChanged(QString)), this, SLOT(bmprange()));
connect(ui->lineEdit_2, SIGNAL(textChanged(QString)), this, SLOT(bmprange()));
connect(ui->lineEdit_3, SIGNAL(textChanged(QString)), this, SLOT(bmprange()));
connect(ui->lineEdit_4, SIGNAL(textChanged(QString)), this, SLOT(bmprange()));
connect(ui->lineEdit_5, SIGNAL(textChanged(QString)), this, SLOT(bmprange()));
connect(ui->lineEdit_6, SIGNAL(textChanged(QString)), this, SLOT(bmprange()));
}
Dialog::~Dialog()
{
delete ui;
}
void Dialog::changeEvent(QEvent *e)
{
QDialog::changeEvent(e);
switch (e->type()) {
case QEvent::LanguageChange:
ui->retranslateUi(this);
break;
default:
break;
}
}
how can i get bmp, xMax, ... to use in mainwindow
I don't speak C++, so sorry for the lack of details. Here's what I'd do:
Catch the closeEvent that you should have when you close your dialog. If your dialog has a OK button, you can use its clicked signal.
Connect it to a particular slot whose functions are (1) to retrieve the texts of all your dialog's QLineEdit in a single object (a QStringList, for example) and (2) to actually close your dialog.
Store the content of this QStringList as an attribute of your main window, or as an independent object you can retrieve from your main window.
Related
I'm using QtCreator to build an interface application.
I'm just getting used to Qt and toying around trying to draw stuff on a QtGraphicsView.
Since I created my interface with the editor, I am retrieving my objects in the code like so (please tell me if this is wrong).
this->m_graphView = this->findChild<QGraphicsView *>("graphicsView");
this->m_graphScene = this->m_graphView->scene();
I have buttons on the interface and already created slots to react to the clicked event.
I'm just trying to draw something (anything) on the graphics view that is on my MainWindow (geometry : [(10,10), 320x240]).
I've been reading examples online and I can't make anything work.
My current code is as follows :
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QDebug>
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
this->m_graphView = this->findChild<QGraphicsView *>("graphicsView");
this->m_graphScene = this->m_graphView->scene();
}
MainWindow::~MainWindow()
{
delete ui;
}
void MainWindow::on_btnDown_clicked()
{
qDebug() << "STUB : button DOWN";
m_graphScene->addLine(0, 0, 42, 42, QPen(QBrush(Qt::black),1));
m_graphView->show();
}
void MainWindow::on_btnLeft_clicked()
{
qDebug() << "STUB : button LEFT";
}
void MainWindow::on_btnUp_clicked()
{
qDebug() << "STUB : button UP";
}
void MainWindow::on_btnRight_clicked()
{
qDebug() << "STUB : button RIGHT";
}
void MainWindow::on_btnShoot_clicked()
{
qDebug() << "STUB : button SHOOT";
}
But annoyingly, it doesn't draw anything and I even get this error when the addLine method is called
QGraphicsScene::addItem: item has already been added to this scene
What's wrong in my code and/or my ways of doing things?
I just want to draw something but can't make it, thank you.
retrieving widget in form
you can get graphicsView pointer (and its scene) more easier.
"ui" member has the pointer to widgets arranged in .form file.
(If you please, see "ui_mainwindow.h" file)
// assign to pointer
QGraphicsView *view = ui->graphicsView;
view->...
// or directly (I like this)
ui->graphicsView->...
so, Mainwindow class don't need "m_graphicsView" member.
graphics view
QGraphicsView need to set scene.(It has no scene at first)
We have to create QGraphicsScene ourselves.
So Mainwindow class need "m_graphicsScene" member.
m_graphicsScene = new QGraphicsScene(this);
ui->graphicsView->setScene(m_graphicsScene);
drawing more easier
If you just want to draw something, you can override "paintEvent" method.
PaintEvent is QWidget's virtual method.
in .h file:
protected:
void paintEvent(QPaintEvent *event);
in .cpp file:
void MainWindow::paintEvent(QPaintEvent *event)
{
// unuse
Q_UNUSED(event);
// pass "this" pointer to painter
QPainter painter(this);
// setPen
// QPen can take "Qt::black" directly as first arg (without QBrush() constructor)
painter.setPen(QPen(Qt::black), 1);
// draw line
painter.drawLine(0, 0, 42, 42);
}
please enjoy Qt!
I have a push button that I'd like to change to a stop button when clicked. Currently the button's text says "auto fire", it runs an endless loop and it's text changes to "stop auto fire" when clicked. My problem is breaking the endless loop by clicking/pressing this button again after the text changes.
Code so far:
void Cpp_Fire::on_auto_fire_clicked()
{
while(true)
{
ui->auto_fire->setText("Stop Auto Fire");
on_manual_fire_clicked();
}
}
I tried inserting a different slot into the loop above that runs when after the button is pressed (it runs when the button is released to be precise) but I couldn't get it to work.
I know this could be done with signals/slots and a separate stop button but I'm unfamiliar with that method and I prefer the method I described.
The problem with your endless loop is that nothing else gets a chance to work.
One approach you could use is to use a QTimer with a short interval to call the on_manual_fire_clicked() method, then have the on_auto_fire_clicked() method be responsible for changing the text on the button and enabling / disabling the timer.
The ui should get enough time to respond to clicks etc if you do it that way.
edit:
For more info on using QTimer have a look at this page:
How to use QTimer
or this tutorial:
http://www.bogotobogo.com/Qt/Qt5_QTimer.php
Here's some code:
mainwindow.h
#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <QMainWindow>
namespace Ui {
class MainWindow;
}
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
explicit MainWindow(QWidget *parent = 0);
~MainWindow();
private slots:
void on_pushButton_clicked();
void timerslot();
private:
Ui::MainWindow *ui;
QTimer* myTimer;
};
#endif // MAINWINDOW_H
mainwindow.cpp
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include<QTimer>
#include<QDebug>
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
myTimer = new QTimer(this);
myTimer->setInterval(500);
myTimer->setSingleShot(false);
connect(myTimer, SIGNAL(timeout()), this, SLOT(timerslot()));
myTimer->start();
}
MainWindow::~MainWindow()
{
delete ui;
}
void MainWindow::timerslot()
{
qDebug() << "timeslot";
}
void MainWindow::on_pushButton_clicked()
{
if ( this->myTimer->isActive() == true ) {
this->myTimer->stop();
ui->pushButton->setText("Start");
} else {
this->myTimer->start(500);
ui->pushButton->setText("Stop");
}
}
I hope you get the idea and can convert it to your needs.
I fully agree Michael's answer.
This will also affect the repaint! (Try to put some windows over your application, while in endless-loop: you should see repaint problems).
Don't use endless-loops, specially not within slots!
Try QTimer, or move object to a QThread.
While in such loop: Give GUI-Thread some time. You can call QCoreApplication::processEvents().. But be careful with this.
A simple (still poor) solution with QTimer could be:
(I found, Michael entered an example in his answer. - Use it.).
//have a QTimer 'timer' in the class, and a connect signal
//timer.timeout() to 'onSingleShotFired()'
void Cpp_Fire::on_auto_fire_clicked()
{
if ( ui->auto_fire->text() == "Stop Auto Fire" )
{
timer.stop();
ui->auto_fire->setText("Start Auto Fire");
}
else
{
//MSEC_AUTOFIRE_DELAY is the delay between the autofire-shots
timer.start( MSEC_AUTOFIRE_DELAY );
ui->auto_fire->setText("Stop Auto Fire");
}
}
I'm creating a simple virtual keyboard in a QDockWidget...
When the widget is docked into the QMainWindow, the selected widget (for example a qdoublespinbox) is highlighted and if I click on the virtual keyboard clearFocus() works...
When the QDockWidget is floating above the window and I click a button, clearFocus doesn't work and I can't see the focused widget in QMainWindow...
How can I force the QDockWidget to not have any focus at all?
Thanks :-)
This is the code:
// class MyVirtualKeyboard : public QDockWidget
void MyVirtualKeyboard::sendKey(Qt::Key key, Qt::KeyboardModifier mod)
{
this->clearFocus();
QMainWindow *w = dynamic_cast<QMainWindow *>(this->parent());
if(w == NULL) return;
QWidget *widget = w->focusWidget();
QString repr = QKeySequence(key).toString();
QKeyEvent *pressEvent = new QKeyEvent(QEvent::KeyPress, key, mod, repr);
QKeyEvent *releaseEvent = new QKeyEvent(QEvent::KeyRelease, key, mod, repr);
qDebug("%s", pressEvent->text().toAscii().data());
MyApplication *app = MyApplication::myInstance();
app->postEvent(widget, pressEvent);
app->postEvent(widget, releaseEvent);
}
void MyVirtualKeyboard::on_BTN_1_clicked()
{
sendKey(Qt::Key_1);
}
...
The clearFocus() call should be unnecessary. Your dock widget and all of its widgets must have the Qt::NoFocus policy.
The code below shows how you might do it.
// https://github.com/KubaO/stackoverflown/tree/master/questions/vkb-focus-18558664
#include <QtGui>
#if QT_VERSION >= QT_VERSION_CHECK(5,0,0)
#include <QtWidgets>
#endif
class Keyboard : public QDockWidget {
Q_OBJECT
QWidget m_widget;
QGridLayout m_layout{&m_widget};
QToolButton m_buttons[10];
void sendKey(Qt::Key key, Qt::KeyboardModifier mod)
{
if (! parentWidget()) return;
auto target = parentWidget()->focusWidget();
if (! target) return;
auto repr = QKeySequence(key).toString();
auto pressEvent = new QKeyEvent(QEvent::KeyPress, key, mod, repr);
auto releaseEvent = new QKeyEvent(QEvent::KeyRelease, key, mod, repr);
qApp->postEvent(target, pressEvent);
qApp->postEvent(target, releaseEvent);
qDebug() << repr;
}
Q_SLOT void clicked() {
auto key = sender()->property("key");
if (key.isValid()) sendKey((Qt::Key)key.toInt(), Qt::NoModifier);
}
public:
explicit Keyboard(const QString & title, QWidget *parent = nullptr) : Keyboard(parent) {
setWindowTitle(title);
}
explicit Keyboard(QWidget *parent = nullptr) : QDockWidget(parent) {
int i{};
for (auto & btn : m_buttons) {
btn.setText(QString::number(i));
btn.setProperty("key", Qt::Key_0 + i);
m_layout.addWidget(&btn, 0, i, 1, 1);
connect(&btn, SIGNAL(clicked()), SLOT(clicked()));
btn.setFocusPolicy(Qt::NoFocus);
++i;
}
setWidget(&m_widget);
setFeatures(QDockWidget::DockWidgetFloatable | QDockWidget::DockWidgetMovable);
}
};
int main(int argc, char ** argv)
{
QApplication a(argc, argv);
QMainWindow w;
w.setCentralWidget(new QLineEdit);
w.addDockWidget(Qt::TopDockWidgetArea, new Keyboard("Keyboard", &w));
w.show();
return a.exec();
}
#include "main.moc"
You can prevent a widget from taking focus by setting QWidget::focusPolicy = Qt::NoFocus.
However, there are two concepts here that you're mixing - the focused control (per window), and the active window (per desktop). I think in the scenario you're describing (a torn-off popup window), the OS window manager is likely to still change the active top-level window even if Qt doesn't set a focused control. That will result in nobody having keyboard focus (which is a valid state!).
So I think a full answer to your question will involve some non-portable bits. I don't know what GUI environment you're working in, but I know some of the answer for Win32, so I'll keep going and hope that's useful:
Win32
There's a pretty good discussion of the state tracking for Win32 on MSDN in the article Win32 Activation and Focus. I'm not aware that Qt does anything to wrap this level, so you'd have to use QWidget::nativeEvent or QCoreApplication::installNativeEventFilter to get at the low-level event. If you can subclass the window, I'd prefer the former, since it's more self-contained.
bool FooWidget::nativeEvent(const QByteArray & eventType, void * message, long * result)
{
#ifdef Q_OS_WIN
if(eventType == "windows_generic_MSG") {
const MSG *msg = reinterpret_cast<MSG *>(message);
if(msg->message == WM_MOUSEACTIVATE) {
*result = MA_NOACTIVATE;
return true;
}
}
#else
#error Need platform-specific code to suppress click-activation
#endif
return false;
}
This should block the click from activating the window (MA_NOACTIVATE), and block Qt from processing it further (return true), while leaving other all events (including the the click, since we didn't use MA_NOACTIVATEANDEAT to block it too) to be processed into QEvents and Qt signals normally (return false at the end).
If you need further low-level access (though I don't think you will), see also QWidget::effectiveWinId() and QWidget::windowHandle
Thanks a lot to Martin Gräßlin for the answer!
My recommendation: check out the virtual keyboard code in KDE Plasma: http://quickgit.kde.org/?p=kdeplasma-addons.git&a=blob&h=5628d6325afe57f85917dad865a07d4116335726&hb=a658d1e257cfca2a43c12714d026ec26f1fdb755&f=applets%2Fplasmaboard%2Fwidget.cpp
Looks like the key is setWindowFlags(Qt::X11BypassWindowManagerHint) and setFocusPolicy(Qt::NoFocus)
MyVirtualKeyboard::MyVirtualKeyboard(QWidget *parent) :
QDockWidget(parent),
ui(new Ui::MyVirtualKeyboard)
{
ui->setupUi(this);
this->connect(this, SIGNAL(topLevelChanged(bool)), this, SLOT(topLevelChanged()));
}
void MyVirtualKeyboard::topLevelChanged()
{
if(this->isWindow())
{
this->setWindowFlags(Qt::Popup | Qt::WindowStaysOnTopHint | Qt::X11BypassWindowManagerHint);
this->setFocusPolicy(Qt::NoFocus);
this->show();
}
}
I think I've found a better way to do it!
Just use this->setAttribute(Qt::WA_X11DoNotAcceptFocus); and voila!
Example:
MyVirtualKeyboard::MyVirtualKeyboard(QWidget *parent) :
QDockWidget(parent),
ui(new Ui::MyVirtualKeyboard)
{
ui->setupUi(this);
this->setAttribute(Qt::WA_X11DoNotAcceptFocus);
}
I would like to highlight a QFrame, if one of it's child widgets has focus (so the users know where to look for the cursor ;-)
using something along
ui->frame->setFocusPolicy(Qt::StrongFocus);
ui->frame->setStyleSheet("QFrame:focus {background-color: #FFFFCC;}");
highlights the QFrame when I click on it, but it loses its focus once one of its child widgets is selected.
Possible approaches:
I could connect() QApplication::focusChanged(old,now) and check each new object if it is a child of my QFrame, but this gets messy.
I could also subclass each child widget and reimplement focusInEvent()/focusOutEvent() and react on that, but with a lot of different widgets, this is also a lot of work.
Is there a more elegant solution?
Well, you can extend QFrame to make it listen on focus change of its children widgets.
Or you can also install an event filter on children widgets to catch QFocusEvent.
Here is an example:
MyFrame.h
#ifndef MYFRAME_H
#define MYFRAME_H
#include <QFrame>
class MyFrame : public QFrame
{
Q_OBJECT
public:
explicit MyFrame(QWidget* parent = 0, Qt::WindowFlags f = 0);
void hookChildrenWidgetsFocus();
protected:
bool eventFilter(QObject *object, QEvent *event);
private:
QString m_originalStyleSheet;
};
#endif // MYFRAME_H
MyFrame.cpp
#include <QEvent>
#include "MyFrame.h"
MyFrame::MyFrame(QWidget *parent, Qt::WindowFlags f)
: QFrame(parent, f)
{
m_originalStyleSheet = styleSheet();
}
void MyFrame::hookChildrenWidgetsFocus()
{
foreach (QObject *child, children()) {
if (child->isWidgetType()) {
child->installEventFilter(this);
}
}
}
bool MyFrame::eventFilter(QObject *object, QEvent *event)
{
if (event->type() == QEvent::FocusIn) {
setStyleSheet("background-color: #FFFFCC;");
} else if (event->type() == QEvent::FocusOut) {
setStyleSheet(m_originalStyleSheet);
}
return QObject::eventFilter(object, event);
}
MainWindow.cpp
#include <QHBoxLayout>
#include <QVBoxLayout>
#include <QLineEdit>
#include "MyFrame.h"
#include "mainwindow.h"
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent)
{
setWindowTitle(tr("Test"));
MyFrame *frame1 = new MyFrame(this);
frame1->setLayout(new QVBoxLayout());
frame1->layout()->addWidget(new QLineEdit());
frame1->layout()->addWidget(new QLineEdit());
frame1->layout()->addWidget(new QLineEdit());
frame1->hookChildrenWidgetsFocus();
MyFrame *frame2 = new MyFrame(this);
frame2->setLayout(new QVBoxLayout());
frame2->layout()->addWidget(new QLineEdit());
frame2->layout()->addWidget(new QLineEdit());
frame2->layout()->addWidget(new QLineEdit());
frame2->hookChildrenWidgetsFocus();
QHBoxLayout *centralLayout = new QHBoxLayout();
centralLayout->addWidget(frame1);
centralLayout->addWidget(frame2);
QWidget *centralWidget = new QWidget();
centralWidget->setLayout(centralLayout);
setCentralWidget(centralWidget);
}
I believe the both answers you were given are wrong. They work for simple cases but are extremely fragile and clumsy. I believe that the best solution is what you actually suggested in your question. I would go for connecting to QApplication::focusChanged(from, to). You simply connect your main frame object to this signal and in the slot you check if the to object (the one which received focus) is a child of your frame object.
Frame::Frame(...)
{
// ...
connect(qApp, &QApplication::focusChanged, this, &Frame::onFocusChanged);
// ...
}
// a private method of your Frame object
void Frame::onFocusChanged(QWidget *from, QWidget *to)
{
auto w = to;
while (w != nullptr && w != this)
w = w->parentWidget();
if (w == this) // a child (or self) is focused
setStylesheet(highlightedStylesheet);
else // something else is focused
setStylesheet(normalStylesheet);
}
The advantage is obvious. This code is short and clean. You connect only one signal-slot, you do not need to catch and handle events. It responds well to any layout changes done after the object is created. And if you want to optimize away unnecessary redrawing, you should cache the information whether any child is focused and change the stylesheet only and only if this cached value gets changed. Then the solution would be prefect.
First, create a simple subclass of QFrame which reimplements the eventFilter(QObject*, QEvent*) virtual function:
class MyFrame : public QFrame {
Q_OBJECT
public:
MyFrame(QWidget *parent = 0, Qt::WindowFlags f = 0);
~MyFrame();
virtual bool eventFilter(QObject *watched, QEvent *event);
};
Use MyFrame instead of QFrame to contain your widgets. Then, somewhere in your code where you create the widgets contained in MyFrame, install an event filter on those widgets:
// ...
m_myFrame = new MyFrame(parentWidget);
QVBoxLayout *layout = new QVBoxLayout(myFrame);
m_button = new QPushButton("Widget 1", myFrame);
layout->addWidget(m_button);
m_button->installEventFilter(myFrame);
//...
At that point, MyFrame::eventFilter() will be called before any event is delivered to the widget, letting you act on it before the widget is aware of it. Within MyFrame::eventFilter(), return true if you want to filter the event out (i.e. you don't want the widget to process the event), or return false otherwise.
bool MyFrame::eventFilter(QObject *watched, QEvent *event)
{
if (watched == m_button) { // An event occured on m_button
switch (event -> type()) {
case QEvent::FocusIn:
// Change the stylesheet of the frame
break;
case QEvent::FocusOut:
// Change the stylesheet back
break;
default:
break;
}
}
return false; // We always want the event to propagate, so always return false
}
I'm trying to get a QDateEdit to allow the QCalendarWidget to show when requested (rather than just on clicking the down arrow). For example, somewhere in my class I should be able to say:
ui.datepicker.showCalendar()
and it should load up the calendar that appears right below the date picker.
It looks like I need to sub-class QDateEdit, as this doesn't work:
QDateEdit *de = new QDateEdit();
de->calendarWidget()->show();
I've also tried sending keyboard commands as dictated when you go through the QDateTimeEdit.cpp source for Qt, but seems my keyboard shortcuts are disabled or something.
Any ideas on what I have to do to sub-class to get this to work? I was thinking of something like:
class MyDateEdit : QDateEdit
{
Q_OBJECT
protected:
void mouseEvent(QEvent *event) {
this.calendarWidget().show();
}
};
But alas that also doesn't seem to compile in or work correctly.
Enable "setCalendarPopup ( bool enable )" in QDateTimeEdit allows to popup the calendar
I was able to figure it out on my own - still no sure how to get QDateEdit to work properly, but I used a QLineEdit and it suited my needs. Just connect QCalendarWidget's "onClick(QDate)" to a slot you create that does a:
setText(date.toString("M/d/yyyy"));
ui->calendar->hide();
Then add an event filter to the QLineEdit using the "OnFocusIn" event that does a "ui->calendar->show();" See: Get a notification/event/signal when a Qt widget gets focus
#Rob S answer
You were right with event filter approach we would do same with QDateEdit.
I am writing the code which extends your approach with QDateEdit :
In mainwindow.h I created a QCalendar pointer (Using QtCreator)
Following is the code of mainwindow.cpp (I am giving out fullcode so that rookies like me can benifit from it)
Make sure you set buttonSymbol and calendarpopup property to false to make it work correctly
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QCalendarWidget>
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
ui->dateEdit->setDate(QDate::currentDate());
widget=new QCalendarWidget(); //widget is QCalendar pointer
ui->verticalLayout->addWidget(widget);
widget->setWindowFlags(Qt::Popup); // we need widget to popup
ui->dateEdit->installEventFilter(this);
connect(widget,SIGNAL(clicked(QDate)),ui->dateEdit,SLOT(setDate(QDate)));
}
MainWindow::~MainWindow()
{
delete ui;
}
bool MainWindow::eventFilter(QObject *object, QEvent *event)
{
if (event->type() == QEvent::InputMethodQuery)
{
if (object == ui->dateEdit)
{
if(widget->isVisible()==false && ui->dateEdit->calendarWidget()->isVisible()==false) // this done to avoid conflict
{
qWarning(QString().number(event->type()).toStdString().c_str());
qWarning(object->objectName().toLatin1().data());
widget->move(ui->dateEdit->mapToGlobal(QPoint(0,ui->dateEdit->height())));
widget->show();
}
}
}
return false;
}
OR :: Alternatively we can use QCalendarWidget provided by dateEdit, though its not much efficient as turing it to Popup will mess with its internal. Give it a shot if you want
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QCompleter>
#include <QCalendarWidget>
#include <QMouseEvent>
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
ui->dateEdit->setDate(QDate::currentDate());
widget = ui->dateEdit->calendarWidget();
widget->setWindowFlags(Qt::Popup);
ui->dateEdit->installEventFilter(this);
//connecting widget with dateedit
ui->dateEdit->setButtonSymbols(QAbstractSpinBox::NoButtons);
ui->dateEdit->setCalendarPopup(true);
connect(widget,SIGNAL(clicked(QDate)),ui->dateEdit,SLOT(setDate(QDate)));
}
MainWindow::~MainWindow()
{
delete ui;
}
bool MainWindow::eventFilter(QObject *object, QEvent *event)
{
if (object == ui->dateEdit)
{
if (event->type() == QEvent::FocusIn || event->type() == QEvent::MouseButtonPress)
{
// WE NEED MOUSE EVENT TO AVOID INTERFERNCE WITH CALENDAR POPUP BUTTON SITUATED AT CORNER OF dateEdit WIDGET
if(widget->isVisible()==false && ( ((QMouseEvent* )event)->x()< (ui->dateEdit->width()-10)))
{
widget->move(ui->dateEdit->mapToGlobal(QPoint(0,ui->dateEdit->height())));
widget->show();
}
}
}
return false;
}
I'd like to offer option similar to #Dr. Xperience's answer that encapsulates calendar widget in QDateEdit subclass:
#include <QDateEdit>
#include <QCalendarWidget>
class DateEdit : public QDateEdit {
Q_OBJECT
public:
explicit DateEdit(QWidget *parent = nullptr);
protected:
virtual void focusInEvent(QFocusEvent *event) override;
private:
QCalendarWidget *calendar = new QCalendarWidget(this);
};
DateEdit::DateEdit(QWidget *parent) : QDateEdit (parent) {
setButtonSymbols(QAbstractSpinBox::NoButtons);
setCalendarPopup(false);
setDate(QDate::currentDate());
calendar->setWindowFlags(Qt::Popup);
connect(calendar, &QCalendarWidget::clicked, this, [&](const QDate &date) {
setDate(date);
calendar->hide();
});
}
void DateEdit::focusInEvent(QFocusEvent *event) {
if (!calendar->isVisible()) {
calendar->setSelectedDate(date());
calendar->move(mapToGlobal(QPoint(0, height())));
calendar->show();
}
return QDateEdit::focusInEvent(event);
}
Warning: If you place this widget using QtDesigner, it will override buttonSymbols and calendarPopup properties, so you have to set it manually to hide QDateEdit's buttons.
Here is my hacky approach to the issue. After fighting for quite a while to have something clean, I read the source code of QDateEditor (which in fact is just a simplified QDateTimeEditor) and it seems to be no clean solution. The following is code for toggle() rather than show(), but still:
// Enable the calendar popup
date_editor->setCalendarPopup(true);
// Show the calendar popup by default
// There seems to be no proper interface to achieve that
// Fake a mouse click on the right-hand-side button
QPointF point = date_editor->rect().bottomRight() - QPointF{5, 5};
QCoreApplication::postEvent(
date_editor,
new QMouseEvent(QEvent::MouseButtonPress, point, Qt::LeftButton,
Qt::LeftButton, Qt::NoModifier));
Using something like this you can keep relying on the editor's validation features.
BTW, another annoying thing about the built-in editor that makes a QLineEdit tempting is that (at least in my case) the keyboard cursor is not shown by default. This is very confusing. To solve this I did:
// Select a section so that the cursor is be visible
date_editor->setSelectedSection(QDateTimeEdit::DaySection);
This or course selects the day section of the date, but if you use keyboard arrows the selection vanished, but you can see the keyboard cursor.