Is it possible to override standart "Stop" (crossed circle) cursor when I drag and drop outside the main window? I have very simple code and that is enough for me. I drag PushButton outside the main window and on release mouse button I get window where mouse was released. Like a standart Windows Spy. So how can I override cursor outside the main window?
header
class DDButton : public QPushButton
{
Q_OBJECT
public:
explicit DDButton(QWidget *parent = 0);
signals:
public slots:
private:
void mousePressEvent(QMouseEvent *event);
};
cpp
void DDButton::mousePressEvent(QMouseEvent *event)
{
if (event->button() == Qt::LeftButton) {
QDrag *drag = new QDrag(this);
QMimeData *mimeData = new QMimeData;
drag->setMimeData(mimeData);
drag->setPixmap(cursor.pixmap());
drag->setHotSpot(QPoint(0,0));
//This block not working
QCursor cursor(Qt::OpenHandCursor);
drag->setDragCursor(cursor.pixmap(), Qt::IgnoreAction);
Qt::DropAction dropAction = drag->exec();
//Do something
qDebug()<<"Press";
}
}
Related
In Class Buttons, I have a btnRightClicked signal and a mousePressEvent slot:
void Buttons::mousePressEvent(QMouseEvent *e)
{
if(e->button() == Qt::RightButton) {
emit btnRightClicked();
}
}
And in mainwindow.cpp, I connect the btnRightClicked signal to onRightClicked slot like this:
connect(&mButtons, SIGNAL(btnRightClicked()), this, SLOT(onRightClicked()));
The onRightClicked slot is like this:
void MainWindow::onRightClicked()
{
qDebug() << "right clicked";
}
But I ran this program, nothing happened. I guess the reason is because I did not connect to the mousePressEvent slot. I am kind of new to Qt, I do not know if I am right or not.
I set up some buttons on the central widget, I want them to have the right clicked event when right click each of them. So how can I make this work?Thanks
Edit:
in button.h:
class Buttons : public QObject
{
Q_OBJECT
public:
Buttons();
QVector<QPushButton*> buttons;
void setButtons(int totalBtns) {
for(int i = 0; i < totalBtns; i++) {
buttons[i]->setObjectName(QString::number(i));
buttons[i]->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Preferred);
}
}
public slots:
void mousePressEvent(QMouseEvent *e) {
if(e->button() == Qt::RightButton) {
emit btnRightClicked();
}
}
signals:
void btnRightClicked();
};
To get the mouse right click on your widget, you need to implement your own button widget.
class MyButton : public QPushButton
{
Q_OBJECT
public:
MyButton(QWidget *parent = Q_NULLPTR);
private slots:
void mousePressEvent(QMouseEvent *e);
signals:
void btnRightClicked();
};
cpp
MyButton:MyButton(QWidget * parent) :
QPushButton(parent)
{
}
void MyButton::mousePressEvent(QMouseEvent *e)
{
if(e->button()==Qt::RightButton)
emit btnRightClicked();
//this forwards the event to the QPushButton
QPushButton::mousePressEvent(e);
}
In your buttons class change the button vector to
QVector<MyButton*> buttons;
Then register the right click event of your MyButton to your signal in Buttons class then forwared the signal to your mainWindow
connect(&mButtons, &Buttons::btnRightClicked,
this, &MainWindow::onRightClicked);
Ok so what i'm trying to do is to create a new QLabel added to a QList and put it where I clicked on the other QLabel where I clicked.
So here is my code:
class CustomLabel : public QLabel
{
Q_OBJECT
public:
CustomLabel();
void mousePressEvent( QMouseEvent* event);
private:
QList<QLabel *> pointsL;
QList<QPoint *> points;
};
void CustomLabel::mousePressEvent(QMouseEvent *event)
{
points << new QPoint(event->pos());
pointsL << new QLabel(this);
pointsL.at(pointsL.size()-1)->setText("+");
pointsL.at(pointsL.size()-1)->setGeometry(QRect(points.at(points.size()-1)->rx(),, points.at(points.size()-1)->ry(), 1, 1));
}
I also tried:
pointsL.at(pointsL.size()-1)->move(points.at(points.size()-1)->rx(), points.at(points.size()-1)->ry());
and this:
void CustomLabel::mousePressEvent(QMouseEvent *event)
{
points << new QPoint(event->pos());
pointsL << new QLabel(this);
pointsL.at(pointsL.size()-1)->setText("+");
pointsL.at(pointsL.size()-1)->move(*points.at(points.size()-1));
pointsL.at(pointsL.size()-1)->setTabOrder(pointsL.at(pointsL.size()-1), this);
}
When I click on the Custom Label nothing happens. The constructor is empty.
Thanks for any answer.
New widgets added after the parent is already visible on screen should be shown explicitly unless they are in a layout.
So basically you should add:
pointsL.back()−>show();
I'd appreciate help creating a top-level window in Qt with the following characteristics. The window must be:
Borderless, titleless and lie on top of all other windows on the desktop (easy)
Draggable by clicking and dragging anywhere inside it (this what I need help with)
Constrained to the top border of the desktop while dragging (relatively easy)
Basically, I'm trying to collapse our QT application to a top-level icon on the top border of the desktop.
You'll find the answer to the first part in: Making a borderless window with for Qt, and the answer to the second part in Select & moving Qwidget in the screen.
Combining the two, and adding the last part is straightforward.
Here's how you could do it:
#include <QtGui>
class W: public QWidget
{
Q_OBJECT
Set up a borderless widget with a few buttons to lock/unlock and quit:
public:
W(QWidget *parent=0)
: QWidget(parent, Qt::FramelessWindowHint), locked(false)
{
QPushButton *lock = new QPushButton("Lock");
QPushButton *unlock = new QPushButton("Unlock");
QPushButton *quit = new QPushButton("&Quit");
connect(lock, SIGNAL(clicked()), this, SLOT(lock()));
connect(unlock, SIGNAL(clicked()), this, SLOT(unlock()));
connect(quit, SIGNAL(clicked()),
QApplication::instance(), SLOT(quit()));
QHBoxLayout *l = new QHBoxLayout;
l->addWidget(lock);
l->addWidget(unlock);
l->addWidget(quit);
setLayout(l);
}
public slots:
void lock() {
locked = true;
move(x(), 0); // move window to the top of the screen
}
void unlock() { locked = false; }
Do the mouse handling:
protected:
void mousePressEvent(QMouseEvent *evt)
{
oldPos = evt->globalPos();
}
void mouseMoveEvent(QMouseEvent *evt)
{
const QPoint delta = evt->globalPos() - oldPos;
if (locked)
// if locked, ignore delta on y axis, stay at the top
move(x()+delta.x(), y());
else
move(x()+delta.x(), y()+delta.y());
oldPos = evt->globalPos();
}
private:
bool locked;
QPoint oldPos;
};
I'm using Qt Creator to create a gui for a mineseeper game.
How can I know a QpushButton clicked with rightclick? for flag in the game.
In other word, which signal used for rightclick?
Create your own button with filter at mousePressEvent slot.
qrightclickbutton.h
#ifndef QRIGHTCLICKBUTTON_H
#define QRIGHTCLICKBUTTON_H
#include <QPushButton>
#include <QMouseEvent>
class QRightClickButton : public QPushButton
{
Q_OBJECT
public:
explicit QRightClickButton(QWidget *parent = 0);
private slots:
void mousePressEvent(QMouseEvent *e);
signals:
void rightClicked();
public slots:
};
#endif // QRIGHTCLICKBUTTON_H
qrightclickbutton.cpp
#include "qrightclickbutton.h"
QRightClickButton::QRightClickButton(QWidget *parent) :
QPushButton(parent)
{
}
void QRightClickButton::mousePressEvent(QMouseEvent *e)
{
if(e->button()==Qt::RightButton)
emit rightClicked();
}
Now connect like this
QRightClickButton *button = new QRightClickButton(this);
ui->gridLayout->addWidget(button);
connect(button, SIGNAL(rightClicked()), this, SLOT(onRightClicked()));
Create a slot in MainWindow.cpp.
void MainWindow::onRightClicked()
{
qDebug() << "User right clicked me";
}
It works for me!
I think QPushButton is internally implemented to listen to left mouse clicks only. But you can easily extend QPushButton and re-implement let's say the mouse release event and do your thing if the right mouse button was pressed, e.g. emit a custom rightClicked() signal for example:
signals:
void rightClicked();
protected:
void mouseReleaseEvent(QMouseEvent *e) {
if (e->button() == Qt::RightButton) emit rightClicked();
else if (e->button() == Qt::LeftButton) emit clicked();
}
... or you can create an overload of the clicked signal that forwards the mouseEvent pointer so you can do the same check outside of the button.
signals:
void clicked(QMouseEvent *);
protected:
void mouseReleaseEvent(QMouseEvent *e) {
emit clicked(e);
}
Then you do the check in the slot you connect the button's clicked(QMouseEvent *) signal to and proceed accordingly.
I just wrote this little helper adapter to make any existing button right-clickable with no need to subclass it:
class CRightClickEnabler : public QObject
{
public:
CRightClickEnabler(QAbstractButton * button): QObject(button), _button(button) {
button->installEventFilter(this);
};
protected:
inline bool eventFilter(QObject *watched, QEvent *event) override {
if (event->type() == QEvent::MouseButtonPress)
{
auto mouseEvent = (QMouseEvent*)event;
if (mouseEvent->button() == Qt::RightButton)
_button->click();
}
return false;
}
private:
QAbstractButton* _button;
};
Usage:
connect(ui->pushButton, &QPushButton::clicked, [](){qDebug() << "Button clicked";});
new CRightClickEnabler(ui->pushButton);
From now on, the clicked signal will be triggered by the right click as well as left click. There's no need to delete this object - it uses ui->pushButton as parent and will be auto-deleted by Qt when the parent is destroyed.
Obviously, you can write 2 lines of code (literally) to declare a new signal here and emit that signal upon right click instead of clicked, if desired.
I'd like to suggest this option as well, without need for event filter/other stuffs...
self.button.released.connect(self.doStuff)
self.button.setContextMenuPolicy(Qt.ContextMenuPolicy.CustomContextMenu)
self.button.customContextMenuRequested.connect(partial(self.doStuff, False))
def doStuff(self,state=True,p=QPoint()):
print("True for left, False for right!",state)
I have a custom QGraphicsView and a custom QGraphicsItem. I want the Item to handle my click if I click in the item, else I want the click to be handled by the View.
But when I click on the item, the item handles the click. This is ok. But if I click somewhere else the click isn't handled at all. All the code in my classes that have anything to do with mouseEvents is below.
class CustomView : public QGraphicsView
{
Q_OBJECT
public:
void mousePressEvent(QGraphicsSceneMouseEvent *event);
};
void CustomView::mousePressEvent(QGraphicsSceneMouseEvent *event){
cout << "pressing in view";
}
class CustomItem : public QGraphicsItem
{
public:
CustomItem(CustomView* widget)
void mousePressEvent(QGraphicsSceneMouseEvent *event);
};
CustomItem::CustomItem(CustomView* widget){
setFlag(ItemIsSelectable);
setFlag(ItemIsMovable);
}
void CustomItem::mousePressEvent(QGraphicsSceneMouseEvent *event){
cout << "pressing in item";
}
It seems that when I remove the mousePressEvent function from the CustomItem class and change in the CustomView the mousePressEvent function to:
void CustomView::mousePressEvent(QMouseEvent *event){
cout << "pressing in view";
}
the CustomView handles all the mouseEvents.
How can I let the CustomItem handles the clicks in the items and the CustomView handle all the other clicks?
Thank you.
EDIT
So now I have changed it to:
class CustomView : public QGraphicsView
{
Q_OBJECT
public:
};
class CustomScene : public QGraphicsScene
{
protected:
void mousePressEvent(QGraphicsSceneMouseEvent *event);
};
void CustomScene::mousePressEvent(QGraphicsSceneMouseEvent *event){
cout << "pressing in scene";
}
class CustomItem : public QGraphicsItem
{
public:
CustomItem(CustomView* widget)
protected:
void mousePressEvent(QGraphicsSceneMouseEvent *event);
};
CustomItem::CustomItem(CustomView* widget){
setFlag(ItemIsSelectable);
setFlag(ItemIsMovable);
}
void CustomItem::mousePressEvent(QGraphicsSceneMouseEvent *event){
cout << "pressing in item";
}
A Click in the scene but not in an item get handled by the scene. But clicks in the items
dont get handled by the items itself, instead it get handled by the scene. Unless if you click 2 times really fast on the items it gets handled by the scene and the item.
Any ideas?
QGraphicsView isn't really a good place to handle scene-specific events. Instead, you'll need to override QGraphicsScene::mousePressEvent. I would recommend something like this:
void CustomScene::mousePressEvent(QGraphicsSceneMouseEvent *event)
{
if (itemAt(event) == NULL)
{
// do stuff if not clicked on an item
}
else
{
QGraphicsScene::mousePressEvent(event); // this forwards the event to the item
}
}
Note that QGraphicsScene::itemAt might give you difficulties if you have items with the ItemIgnoresTransformations flag set to true. Look to the docs for QGraphicsScene::itemAt for how to resolve this.