I'm trying to load in a CSS file for formatting across my entire Qt application. Currently I have my "stylesheet.css" file in the same folder as my built exe (both debug and release). However, upon running the program it produces no errors and simply outputs "test: ", so it's clearly not finding the file or perhaps I'm not reading it properly?
Forgive me if it's a dumb mistake - I'm fairly new to both Qt and C++.
#include "mainwindow.h"
#include "qfile.h"
#include "qtextstream.h"
#include <QApplication>
#include <iostream>
int main(int argc, char *argv[])
{
QApplication program(argc, argv);
QFile styleFile("stylesheet.css");
styleFile.open(QIODevice::ReadOnly);
QTextStream textStream(&styleFile);
QString styleSheet = textStream.readAll();
styleFile.close();
program.setStyleSheet(styleSheet);
std::cout << "test: " << styleSheet.toStdString() << std::endl;
MainWindow w;
w.showMaximized();
return program.exec();
}
After digging a bit deeper, it turns out I was lacking a QRC file (which I wasn't even aware existed). So I created a resource (QRC) file, added the prefix "/style", and then added my stylesheet to that prefix. It now works flawlessly. Also, at one point I changed the .css to a .qss (thought I should mention it, although I doubt it made any difference).
Here's the final code:
#include "mainwindow.h"
#include "qfile.h"
#include "qtextstream.h"
#include <QApplication>
int main(int argc, char *argv[])
{
QApplication program(argc, argv);
QFile styleFile(":/style/stylesheet.qss");
if(styleFile.open(QIODevice::ReadOnly))
{
QTextStream textStream(&styleFile);
QString styleSheet = textStream.readAll();
styleFile.close();
program.setStyleSheet(styleSheet);
}
MainWindow w;
w.showMaximized();
return program.exec();
}
Change
QFile styleFile("stylesheet.css");
to
QFile styleFile("C:/path/to/stylesheet.css");
You need to pass the full file path for your program to find the file. If you just give its name but not the directory it's in, the program will search for it in the current directory only (which is not necessarily the directory of your exe file), and if it's not there, it won't find it.
If you want to deploy this CSS file with your application, you are looking for the Qt resource file support.
its coz u shoud uncheck " shadow build " under projects. and check the path of the project . and make sure that .css file is inside the project folder
Related
I am trying to keep track of files in a directory. Not only do I want to get notion of new files being created or existing files being deleted, but I also would like to watch for modifications done to existing files (i.e., when the file content is modified).
QFileSystemWatcher allows for watching directories and files. Given a large number of files in the directory it is not feasible to add every file to the watcher (QFileSystemWatcher::addFile()). In return, however, it would be totally sufficient to hinge the modification of a file on its modification time alone.
Now I've set up a little test like this:
#include <QtCore>
#include <QtWidgets>
int main(int argc, char *argv[])
{
QApplication app(argc, argv);
QFileSystemWatcher *w = new QFileSystemWatcher;
w->addPath("/tmp/xxx");
QObject::connect(w, &QFileSystemWatcher::directoryChanged,
[]{ qDebug() << "change"; }
);
QFile f("/tmp/xxx/the.file");
f.open(QFile::WriteOnly);
f.write("blabla");
f.setFileTime(QDateTime::fromSecsSinceEpoch(10000), QFile::FileModificationTime);
f.close();
QDialog d;
d.show();
app.exec();
}
Yet whatever I try within this program (writing to the file, setting the file times) no change is ever detected.
But what strikes me is that if I use touch on the file the change is detected. So what on earth does touch do differently?
Obviously I am running Linux.
I'm simply looking for a quick and easy solution on how to change the default source code (if at all possible) for when you open a qtCreator C++ project.
As soon as you open up a new project you see something like below in your main.cpp file.
#include <QCoreApplication>
int main(int argc, char *argv[]) {
QCoreApplication a(argc, argv);
return a.exec(); }
I'm wondering if there's a way to change this code snippet to user defined code. I personally just think its a hassle to wipe all this code out every time I create a project and would rather it look something like below, when I make a new project.
#include <QCoreApplication>
#include <iostream>
using namespace std;
int main() {
}
Anyways, open to all different types of solutions just let me know...
Problem
I am currently learning Qt by writing a mp3 player on Windows. Now I want to use QSettings to save changes made to the application. I already tried saving the changes to the registry (which works fine) but I would like to store them in an ini-file (for portability reasons).
But for some reason I am unable to create or write an existing ini-file (reading works perfectly).
What I've tried so far
run the application with admin privileges, which works but is not viable all the time
use QStandardPath to ensure a writable path
MCVE
#include <QCoreApplication>
#include <QSettings>
#include <QDebug>
#include <QFileInfo>
#include <QStandardPaths>
int main(int argc, char *argv[])
{
QCoreApplication app(argc, argv);
QString path = QStandardPaths::writableLocation(QStandardPaths::DesktopLocation);
path = path + "/settings.ini";
QFileInfo info(path);
qDebug() << info.exists();
qDebug() << info.isWritable();
QSettings settings(path, QSettings::IniFormat);
settings.setValue("key", "value");
settings.sync();
return 0;
}
Question
Why does the ini-file only get generated / updated when the application is running with admin privileges? Is there any way to do it without?
It's not clear what versions of OS are used. Windows 10 (version 1709) come with new feature called "Protected folders" to prevent e.g. Ransomware threats. You can reconfigure it somewhere. It disallow write access to desktop/documents etc.
But more preferable approach will be to store ini file into other location e.g. AppData.
I have some trouble trying to set an icon for my QT application.
The icon is named "room.ico" and is on the same directory as the source file.
Here is the code :
#include <QApplication>
#include <QWidget>
int main( int argc, char *argv[ ] )
{
QApplication app( argc, argv) ;
QWidget fenetre;
fenetre.setWindowIcon(QIcon("room.ico")); // Nothing happens
fenetre.setWindowTitle("Heloo");
fenetre.show();
return app.exec() ;
}
I have tried to add win32:RC_ICONS += room.ico in the .pro file but that didn't work. I have also tried "./room.ico" but still no icon.
I have tried to use this :
QPixmap pixmap = QPixmap ("room.ico");
fenetre.setWindowIcon(QIcon(pixmap));
And guess what !!! it didn't work ... i'm just a newbie to QT :p
Any suggestions will be appreciated , thanks
QT's documentation for QWindow::setWindowIcon should be what you need.
Make an icon file (you appear to have done this already: room.ico
Add your icon file to a QT resource file (.qrc or .rc) which you should add to your project (the documentation discusses how to do this
Use setWindowIcon and pass in a QIcon:
app.setWindowIcon(QIcon(":/room.ico")); (this assumes your file is in the resource file)
Your problem appears to be that you didn't prepend :/ when passing in the filename to QIcon.
I receive this error (title, below) whenever I try to run the following code:
#include <QCoreApplication>
#include <QQuickView>
int main(int argc, char *argv[]){
QCoreApplication app(argc, argv);
QQuickView view;
view.setSource(QUrl::fromLocalFile("app.qml"));
QObject *object = (QObject*)view.rootObject();
view.show();
delete object;
return app.exec();
}
Cannot create window: no screens available
The program has unexpectedly finished.
All I can find online for that error are bug reports arising from specific conditions significantly more involved than the above.
app.qml is a file that runs fine alone, i.e. without the above C++ and in a separate project configured as a 'Qt Quick UI'. Giving it's qrc:// path, or deliberately specifying a file which does not exist has no effect.
Note the QObject* cast - this was not present in the docs, but without it:
/main.cpp:11: error: cannot initialize a variable of type 'QObject *' with an rvalue of type 'QQuickItem *'
How should this be done?
The QCoreApplication can be used with console application, not with GUI ones, i.e. you have to use a QGuiApplication object. It seems to me that you created a console application instead of a graphical one.
You can create a proper application via the Qt Quick Application, add your "app.qml" as a resource to that project and call such a file instead of the default "main.qml", provided by the project template.
If you want to quick fix your current project, just check that the .pro file is set to import GUI libraries:
QT += gui qml quick
Set your qml file as a resource:
Create a new resource file via file -> new File or Project... -> Qt -> Qt Resource File
Right click the newly created .qrc file and click add existing file to add your "app.qml" file
Finally, rewrite your main like this:
#include <QQuickView>
#include <QGuiApplication>
int main(int argc, char *argv[])
{
QGuiApplication a(argc, argv); // GUI APPLICATION!!!
QQuickView view;
view.setSource(QUrl(QStringLiteral("qrc:///app.qml")));
view.show();
return a.exec();
}
However, going for the Qt Quick Application project would be the wiser choice.