Following program crashes:
#include <QtGui/qkeysequence.h>
inline const QKeySequence my_key_sequence = Qt::CTRL + Qt::Key_E;
inline const QKeySequence my_other_key_sequence = QKeySequence::Copy;
int main() {}
Why does it crash and how do I get around this?
Hello friends, I have the following code:
#include "dialog.h"
#include "ui_dialog.h"
#include <QMessageBox>
#include <QFileDialog>
Dialog::Dialog(QWidget *parent)
: QDialog(parent)
, ui(new Ui::Dialog)
{
ui->setupUi(this);
}
Dialog::~Dialog()
{
delete ui;
}
void Dialog::on_toolButton_clicked()
{
QString fileName=QFileDialog::getOpenFileName(this,"Abrir imagenes",
QDir::rootPath(),"Imagenes (*.jpg *.jpeg *.png)");
if(fileName.isEmpty())
{
return;
}
ui->label->setPixmap(QPixmap(fileName));
ui->label->setScaledContents(true);
}
what I want is that when loading an image in the QLabel it adjusts to the size of the control but it doesn't work, I already put it in the constructor but it didn't work either; I tried to mark the property in the graphic designer but nothing, I would like to know why it is not working.
Hi All,
I'm trying to make a cross compiled Qt.
But when I run the configure I get the following error:
with the following arguments:
./configure -device armadaxp --device-option=CROSS_COMPILE=/usr/local/arm-unknown-linux-gnueabi/bin/arm-unknown-linux-gnueabi- -sysroot /usr/local/arm-unknown-linux-gnueabi/arm-unknown-linux-gnueabi/sysroot -no-opengl -opensource -confirm-license -nomake examples -nomake tests
Qt will be installed into '/usr/local/arm-unknown-linux-gnueabi/arm-unknown-linux-gnueabi/sysroot/usr/local/Qt-5.12.5'.
Prior to reconfiguration, make sure you remove any leftovers from
the previous build.
/home/osboxes/qtbase/mkspecs/features/qt_docs_targets.prf:31: 'prepareRecursiveTarget' is not a recognized test function.
/home/osboxes/qtbase/mkspecs/features/qt_docs_targets.prf:31: 'prepareRecursiveTarget' is not a recognized test function.
/home/osboxes/qtbase/mkspecs/features/qt_docs_targets.prf:31: 'prepareRecursiveTarget' is not a recognized test function.
/home/osboxes/qtbase/mkspecs/features/qt_docs_targets.prf:31: 'prepareRecursiveTarget' is not a recognized test function.
/home/osboxes/qtbase/mkspecs/features/qt_docs_targets.prf:31: 'prepareRecursiveTarget' is not a recognized test function.
/home/osboxes/qtbase/mkspecs/features/qt_docs_targets.prf:31: 'prepareRecursiveTarget' is not a recognized test function.
/home/osboxes/qtbase/mkspecs/features/qt_docs_targets.prf:31: 'prepareRecursiveTarget' is not a recognized test function.
/home/osboxes/qtbase/mkspecs/features/qt_docs_targets.prf:31: 'prepareRecursiveTarget' is not a recognized test function.
/home/osboxes/qtbase/mkspecs/features/qt_docs_targets.prf:31: 'prepareRecursiveTarget' is not a recognized test function.
/home/osboxes/qtbase/mkspecs/features/testcase_targets.prf:4: 'prepareRecursiveTarget' is not a recognized test function.
/home/osboxes/qtbase/mkspecs/features/testcase_targets.prf:13: 'prepareRecursiveTarget' is not a recognized test function.
And when I try to make:
osboxes@osboxes:~/qtbase$ make
cd src/ && ( test -e Makefile || /home/osboxes/qtbase/bin/qmake -o Makefile /home/osboxes/qtbase/src/src.pro ) && make -f Makefile
Project ERROR: Could not find feature concurrent.
make: *** [Makefile:51: sub-src-make_first] Error 3
Does anyone has an idea what i'm doing wrong?
The definition of connect is as below:
inline QMetaObject::Connection QObject::connect(const QObject *asender, const char *asignal,
const char *amember, Qt::ConnectionType atype) const
{ return connect(asender, asignal, this, amember, atype); }
And I can't understand how it work like
connect(new QSpinBox, static_cast<void(QSpinBox::*)(int)>(&QSpinBox::valueChanged), [=](auto v){});
Why function pointer and lambda function can convert to
const char *
?
I am implementing a search function for my help viewer based on QTextBrowser. What I would like to do, once a page has been loaded containing the search item text, is to highlight each of the occurrences of the text with background color = yellow. The user can then reload the document (hitting F5 calls the widget's reload() function) to remove the highlighting.
It appears that I can fetch the text block from the QTextDocument and the corresponding QTextFormat easily enough, but it seems that there is no way to edit it (i.e., change the background color of a selection)?
What would be the best way to implement this?
I have the following code example, which works fine and makes one characteristic to one service. I need to add a second characteristic ipData
QLowEnergyAdvertisingData leAdd;
leAdd.setDiscoverability(QLowEnergyAdvertisingData::DiscoverabilityGeneral);
leAdd.setLocalName("SensorServer");
leAdd.setIncludePowerLevel(true);
QList<QBluetoothUuid> servicesList;
servicesList.append(QBluetoothUuid::EnvironmentalSensing);
leAdd.setServices(servicesList);
QLowEnergyCharacteristicData chData, ipData;
chData.setUuid(QBluetoothUuid::TemperatureMeasurement);
chData.setValue(QByteArray(21,0)); //reset all the characteristic field
chData.setValueLength(2,21); //length of the characteristic from 2 to 21 bytes - maximum character length of a characteristics
chData.setProperties(QLowEnergyCharacteristic::WriteNoResponse | QLowEnergyCharacteristic::Write);
const QLowEnergyDescriptorData descriptorData(QBluetoothUuid::ClientCharacteristicConfiguration, QByteArray(2, 0));
chData.addDescriptor(descriptorData);
// ipData.setUuid(QBluetoothUuid::WeightScale);
// ipData.setValue(QByteArray(21,0)); //reset all the characteristic field
// ipData.setValueLength(2,21); //length of the characteristic from 2 to 21 bytes - maximum character length of a characteristics
// ipData.setProperties(QLowEnergyCharacteristic::Read);
// const QLowEnergyDescriptorData ipdescriptorData(QBluetoothUuid::ClientCharacteristicConfiguration, QByteArray(2, 0));
// ipData.addDescriptor(ipdescriptorData);
QLowEnergyServiceData serviceData;
serviceData.setUuid(QBluetoothUuid::Temperature);
serviceData.setType(QLowEnergyServiceData::ServiceTypePrimary);
serviceData.addCharacteristic(chData);
// serviceData.setUuid(QBluetoothUuid::WeightScale);
// serviceData.setType(QLowEnergyServiceData::ServiceTypeSecondary);
// serviceData.addCharacteristic(ipData);
controller = QLowEnergyController::createPeripheral();
connect(controller,
QLowEnergyService *service = controller->addService(serviceData);
QLowEnergyCharacteristic characteristic = service->characteristic(QBluetoothUuid::TemperatureMeasurement);
// QLowEnergyCharacteristic characteristic1 = service->characteristic(QBluetoothUuid::WeightScale);
When i added the second service ipData, i don't get it in my mobile.
where is my mistake ?
I don't if there is already a function for this, but what i want to do is:
when i click on the diagramscene i want it to add 2 items, one QGraphicsSvgItem and one QGraphicsTextItem, but here is the deal, when i drag and drop my QGraphicsSvgItem i want the QGraphicsTextItem to keep it up with position, kind of following him, in a same position towards the QGraphicsSvgItem.
How can I do this?
Hey!
I just started using Qt and playing with it currently. It is still a huge mystery box to me, so I spent most of my time in the documents but now I couldn't figure out where to look so I came here.
I'm currently making a clone IDE/Code Editor type of program. I basically just added compile option to basic notepad example with QProcess which works. Now what I want to do is to implement a simultaneous file editing, or turn my program into online coding platform clone.
I was thinking maybe I could store some users in MySQL database. And when user1 opens a new document and invites user2, they both can edit user1's document. interviewing.io is a nice example to what I mean.
I don't want anyone to just come up with a direct solution. My intention is to learn but I couldn't find a starting point. I saw Session Management page but I'm not sure if that's what I need. I would be really happy if anyone would show me the way.
Btw, I'm on a Windows platform if that matters.
Thanks in advance!
g++ -c -pipe -O2 -Wall -std=c++11 -W -D_REENTRANT -fPIC -DQT_NO_DEBUG -DQT_GUI_LIB -DQT_CORE_LIB -I. -I. -isystem /usr/include/qt5 -isystem /usr/include/qt5/QtWidgets -isystem /usr/include/qt5/QtGui -isystem /usr/include/qt5/QtCore -I. -isystem /usr/include/libdrm -I/usr/lib64/qt5/mkspecs/linux-g++ -o GitStatusDialog.o GitStatusDialog.cpp
In file included from /usr/include/qt5/QtWidgets/qstyleoption.h:59,
from /usr/include/qt5/QtWidgets/qabstractitemdelegate.h:45,
from /usr/include/qt5/QtWidgets/qabstractitemview.h:47,
from /usr/include/qt5/QtWidgets/qlistview.h:44,
from /usr/include/qt5/QtWidgets/qlistwidget.h:44,
from /usr/include/qt5/QtWidgets/QListWidget:1,
from ui_GitStatusDialog.h:19,
from GitStatusDialog.h:8,
from GitStatusDialog.cpp:9:
/usr/include/qt5/QtWidgets/qtabwidget.h:126:10: error: ‘bool QTabWidget::hasHeightForWidth() const’ marked ‘override’, but does not override
126 | bool hasHeightForWidth() const override;
| ^~~~~~~~~~~~~~~~~
make: *** [Makefile:713: GitStatusDialog.o] Error 1
I've defined -std=c++11 but it doesn't make a difference. If I include <QtGui/QListWidget> instead of <QtWidgets/QListWidget in ui_GitStatusDialog.h it compiles but gives me linker errors for everything in moc_GitStatusDialog.cpp.
I've also tried including <QtCore> and <QtGui> in ui_GitStatusDialog.h but nothing helps.
Thank you.